Rule2023-23581
Reliability Standards To Address Inverter-Based Resources
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Published
October 30, 2023
Effective
December 29, 2023
Issuing agencies
Energy DepartmentFederal Energy Regulatory Commission
Abstract
The Federal Energy Regulatory Commission (Commission) is directing the North American Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability Organization, to develop new or modified Reliability Standards that address reliability gaps related to inverter-based resources in the following areas: data sharing; model validation; planning and operational studies; and performance requirements. The Commission is also directing NERC to submit to the Commission an informational filing within 90 days of the issuance of this final action that includes a detailed, comprehensive standards development plan providing that all new or modified Reliability Standards necessary to address the inverter-based resource- related reliability gaps identified in this final action be submitted to the Commission by November 4, 2026.
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[Federal Register Volume 88, Number 208 (Monday, October 30, 2023)]
[Rules and Regulations]
[Pages 74250-74289]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-23581]
[[Page 74249]]
Vol. 88
Monday,
No. 208
October 30, 2023
Part II
Department of Energy
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Federal Energy Regulatory Commission
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18 CFR Part 40
Reliability Standards To Address Inverter-Based Resources; Final Rule
Federal Register / Vol. 88 , No. 208 / Monday, October 30, 2023 /
Rules and Regulations
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DEPARTMENT OF ENERGY
Federal Energy Regulatory Commission
18 CFR Part 40
[Docket No. RM22-12-000; Order No. 901]
Reliability Standards To Address Inverter-Based Resources
AGENCY: Federal Energy Regulatory Commission, Department of Energy.
ACTION: Final action.
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SUMMARY: The Federal Energy Regulatory Commission (Commission) is
directing the North American Electric Reliability Corporation (NERC),
the Commission-certified Electric Reliability Organization, to develop
new or modified Reliability Standards that address reliability gaps
related to inverter-based resources in the following areas: data
sharing; model validation; planning and operational studies; and
performance requirements. The Commission is also directing NERC to
submit to the Commission an informational filing within 90 days of the
issuance of this final action that includes a detailed, comprehensive
standards development plan providing that all new or modified
Reliability Standards necessary to address the inverter-based resource-
related reliability gaps identified in this final action be submitted
to the Commission by November 4, 2026.
DATES: This rule is effective December 29, 2023.
FOR FURTHER INFORMATION CONTACT:
Eugene Blick (Technical Information), Office of Electric
Reliability, Federal Energy Regulatory Commission, 888 First Street NE,
Washington, DC 20426, (202) 502-8803, <a href="/cdn-cgi/l/email-protection#44013123212a216a06282d272f04222136276a232b32"><span class="__cf_email__" data-cfemail="2b6e5e4c4e454e0569474248406b4d4e5948054c445d">[email protected]</span></a>.
Felicia West (Legal Information), Office of the General Counsel,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, (202) 502-8948, <a href="/cdn-cgi/l/email-protection#f6b0939a9f959f97d8a1938582b690938495d8919980"><span class="__cf_email__" data-cfemail="2660434a4f454f470871435552664043544508414950">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Table of Contents
Paragraph
Nos.
I. Information............................................. 1
II. Background............................................. 9
A. Section 215 of the FPA and the Mandatory Reliability 9
Standards.............................................
B. Inverter-Based Resources............................ 11
C. Notice of Proposed Rulemaking....................... 16
III. Need for Reform....................................... 24
A. Current Actions Are Insufficient To Address IBR 26
Reliability Risks.....................................
B. Existing Reliability Standards Do Not Adequately 37
Address IBR Reliability Risks.........................
1. Data Sharing.................................... 37
2. Data and Model Validation....................... 42
3. Planning and Operational Studies................ 49
4. Performance Requirements........................ 50
IV. Discussion............................................. 53
A. Commission Authority To Direct the ERO To Develop 59
New or Modified Reliability Standards Under Section
215 of the FPA........................................
1. Comments........................................ 60
2. Commission Determination........................ 63
B. Data Sharing........................................ 66
1. Registered IBR Data Sharing..................... 68
2. Disturbance Monitoring Data Sharing............. 81
3. Unregistered IBR and IBR-DER Data Sharing....... 87
C. Data and Model Validation........................... 110
1. Approved Component Models....................... 112
2. Verification of IBR Plant Dynamic Model 128
Performance.......................................
3. Validating and Updating System Models........... 151
4. Need for Coordination When Creating and Updating 158
Planning, Operational, and Interconnection-Wide
Data and Models...................................
D. Planning and Operational Studies.................... 162
1. Comments........................................ 167
2. Commission Determination........................ 174
E. Performance Requirements............................ 178
1. Registered IBR Frequency and Voltage Ride 178
Through Requirements..............................
2. Bulk-Power System Planners and Operators Voltage 196
Ride Through Mitigation Activities................
3. Post-Disturbance IBR Ramp Rate Interactions and 200
Phase Lock Loop Synchronization...................
F. Informational Filing and Reliability Standard 212
Development Timeline..................................
1. Comments........................................ 214
2. Commission Determination........................ 222
V. Information Collection Statement........................ 231
VI. Environmental Analysis................................. 234
VII. Regulatory Flexibility Act............................ 235
VIII. Document Availability................................ 237
IX. Effective Date and Congressional Notification.......... 240
Appendix A: Commenter Names................................
Appendix B: NERC IBR Resources Cited in the Final Action...
[[Page 74251]]
I. Introduction
1. Pursuant to section 215(d)(5) of the Federal Power Act (FPA),\1\
the Federal Energy Regulatory Commission (Commission) directs the North
American Electric Reliability Corporation (NERC), the Commission-
certified Electric Reliability Organization (ERO), to submit new or
modified Reliability Standards \2\ that address specific matters
pertaining to the impacts of inverter-based resources (IBR) \3\ on the
reliable operation \4\ of the Bulk-Power System.\5\ As proposed in the
notice of proposed rulemaking (NOPR), we direct NERC to develop new or
modified Reliability Standards addressing reliability gaps pertaining
to IBRs in four areas: (1) data sharing; (2) model validation; (3)
planning and operational studies; and (4) performance requirements.\6\
NERC may propose to develop new or modified Reliability Standards that
address our concerns in an equally efficient and effective manner;
however, NERC's proposal should explain how the new or modified
Reliability Standards address the Commission's concerns discussed in
this final action.\7\
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\1\ 16 U.S.C. 824o(d)(5) (the Commission may order the Electric
Reliability Organization (ERO) to submit to the Commission a
proposed Reliability Standard or a modification to a Reliability
Standard that addresses a specific matter if the Commission
considers such a new or modified Reliability Standard appropriate to
carry out FPA section 215).
\2\ The FPA defines Reliability Standard as requirements for the
operation of existing Bulk-Power System facilities, including
cybersecurity protection, and the design of planned additions or
modifications to such facilities to the extent necessary to provide
for reliable operation of the Bulk-Power System, but the term does
not include any requirement to enlarge such facilities or to
construct new transmission capacity or generation capacity. Id.
824o(a)(3); see also 18 CFR 39.1.
\3\ This final action uses the term IBR generally to include all
generation resources that connect to the electric power system using
power electronic devices that change direct current (DC) power
produced by a resource to alternating current (AC) power compatible
with distribution and transmission grids. IBRs may refer to solar
photovoltaic (PV), wind, fuel cell, and battery storage resources.
\4\ The FPA defines reliable operation as operating the elements
of the Bulk-Power System within equipment and electric system
thermal, voltage, and stability limits so that instability,
uncontrolled separation, or cascading failures of such system will
not occur as a result of a sudden disturbance, including a
cybersecurity incident, or unanticipated failure of system elements.
16 U.S.C. 824o(a)(4); see also 18 CFR 39.1.
\5\ The Bulk-Power System is defined in the FPA as facilities
and control systems necessary for operating an interconnected
electric energy transmission network (or any portion thereof), and
electric energy from generating facilities needed to maintain
transmission system reliability. The term does not include
facilities used in the local distribution of electric energy. 16
U.S.C. 824o(a)(1); see also 18 CFR 39.1.
\6\ Reliability Standards to Address Inverter-based Res., Notice
of Proposed Rulemaking, 87 FR 74541 (Dec. 6, 2022), 181 FERC ]
61,125, at P 1 (2022) (NOPR).
\7\ See, e.g., Mandatory Reliability Standards for the Bulk-
Power Sys., Order No. 693, 72 FR 16416 (Apr. 4, 2007), 118 FERC ]
61,218, at PP 186, 297, order on reh'g, Order No. 693-A, 72 FR 40717
(July 25, 2007), 120 FERC ] 61,053 (2007) (``[W]here the Final Rule
identifies a concern and offers a specific approach to address the
concern, we will consider an equivalent alternative approach
provided that the ERO demonstrates that the alternative will address
the Commission's underlying concern or goal as efficiently and
effectively as the Commission's proposal.'').
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2. We take this action in light of the rapid change in the mix of
generation resources \8\ connecting to the Bulk-Power System, including
the addition of an ``unprecedented proportion of nonsynchronous
resources'' \9\ projected to connect over the next decade, including
many generation resources that employ inverters, rectifiers, and
converters \10\ to provide energy to the Bulk-Power System. According
to NERC, the rapid integration of IBRs is ``the most significant driver
of grid transformation'' on the Bulk-Power System.\11\
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\8\ The Reliability Standards use both terms ``generation
resources'' and ``generation facilities'' to define sources of
electric power on the transmission system. This final action uses
the term ``generation resources.''
\9\ NERC, 2020 Long Term Reliability Assessment Report, 9 (Dec.
2020), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf</a> (2020 LTRA
Report).
\10\ An inverter is a power electronic device that inverts DC
power to AC sinusoidal power. A rectifier is a power electronic
device that rectifies AC sinusoidal power to DC power. A converter
is a power electronic device that performs rectification and/or
inversion. Consistent with NERC's terminology, this order uses the
term ``inverter'' to refer to generating facilities that use power
electronic inversion, rectification, and conversion. NERC, Inverter-
Based Resource Performance and Analysis Technical Workshop, 29 (Feb.
2019), <a href="https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf">https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf</a>.
\11\ NERC, Inverter-Based Resource Strategy: Ensuring
Reliability of the Bulk Power System with Increased Levels of BPS-
Connected IBRs, 1 (June 2022), <a href="https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf">https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf</a> (NERC IBR Strategy).
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3. The Reliability Standards, first approved by the Commission in
2007, were developed to apply to the types of generation resources
prevalent at that time--nearly exclusively synchronous generation
resources--to ensure the reliable operation of the Bulk-Power System.
As a result, the Reliability Standards may not account for the material
technological differences between the response of synchronous
generation resources and the response of IBRs to the same disturbances
on the Bulk-Power System.\12\
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\12\ See, e.g., NERC, 2013 Long-Term Reliability Assessment, 22
(Dec. 2013), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf</a> (2013 LTRA
Report) (finding that reliably integrating high levels of variable
resources into the Bulk-Power System would require ``significant
changes to traditional methods used for system planning and
operation,'' including requiring ``new tools and practices,
including potential enhancements to . . . Reliability Standards or
guidelines to maintain [Bulk-Power System] reliability.'').
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4. We also take this action because, as discussed in more detail in
section III below, we find that the currently effective Reliability
Standards do not ensure that Bulk-Power System planners and operators
\13\ have the necessary tools to plan for and reliably integrate IBRs
into the Bulk-Power System or to plan for IBRs connected to the
distribution system that in the aggregate have a material impact on the
Bulk-Power System (IBR-DER). IBRs, individually and in the aggregate,
and IBR-DERs in the aggregate can have a material impact on the
reliable operation of the Bulk-Power System.\14\ Additionally, the
Reliability Standards do not contain performance requirements that are
unique to IBRs and are necessary to ensure that IBRs operate in a
predictable and reliable manner.
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\13\ Bulk-Power System planners and operators include planning
coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities, and any other
functional entity NERC may identify as applicable to meet the
directives in this final action.
\14\ NERC reports do not always differentiate between IBRs based
on type, or between those subject to Reliability Standards and those
located on the distribution system. Where necessary to describe our
directives, however, we differentiate between IBRs registered with
NERC (or which will be registered pursuant to the Commission's
directives in Registration of Inverter-based Resources, 181 FERC ]
61,124 (2022) (IBR Registration Order)) and therefore subject to the
Reliability Standards (i.e., registered IBR), IBRs connected
directly to the Bulk-Power System but not registered with NERC and
therefore not subject to the Reliability Standards (i.e.,
unregistered IBRs), and IBRs connected to the distribution system
that in the aggregate have a material impact on the Bulk-Power
System (i.e., IBR-DER). Although the remaining subset of
unregistered IBRs and IBR-DERs in the aggregate will not be subject
to the mandatory and enforceable Reliability Standards set forth
herein, they may be subject to provision of data and information to
their respective transmission owners and distribution providers, as
applicable, in accordance with their specific interconnection
agreements. We encourage NERC to continue its efforts to review and
evaluate whether reliability gaps continue to remain and if new or
modified functional registration categories or Reliability Standards
are necessary. See infra note 365 (discussing NERC's estimate of the
percentage of IBRs to be registered under its registration work
plan).
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5. As discussed in greater detail below, we therefore direct NERC,
pursuant to section 215(d)(5) of the FPA and Sec. 39.5(f) of the
Commission's regulations, to develop new or modified Reliability
Standards that address the following specific issues:
<bullet> IBR Data Sharing: The Reliability Standards must require
that generator owners, transmission owners, and
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distribution providers share validated modeling, planning, operations,
and disturbance monitoring data for all IBRs with planning
coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities so that the latter
group has the necessary data to predict the behavior of registered and
unregistered IBRs individually and in the aggregate, as well as IBR-
DERs in the aggregate, and their impact on the reliable operation of
the Bulk-Power System.
<bullet> IBR Model Validation: The Reliability Standards must
require that all IBR models are comprehensive, validated, and updated
in a timely manner, so that planning coordinators, transmission
planners, reliability coordinators, transmission operators, and
balancing authorities can adequately predict the behavior of registered
and unregistered IBRs individually and in the aggregate, as well as
IBR-DERs in the aggregate, and their impacts on the reliable operation
of the Bulk-Power System.
<bullet> IBR Planning and Operational Studies: The Reliability
Standards must require that planning and operational studies include
validated IBR models to assess the reliability impacts of registered
and unregistered IBRs individually and in the aggregate, as well as
IBR-DERs in the aggregate, on the reliable operation of the Bulk-Power
System. The Reliability Standards must require that planning and
operational studies assess the impacts of all IBRs within and across
planning and operational boundaries for normal operations and
contingency event conditions.
<bullet> IBR Performance Requirements: The Reliability Standards
must ensure that registered IBRs will provide frequency and voltage
support during frequency and voltage excursions in a manner necessary
to contribute toward the overall system needs for essential reliability
services.\15\ The Reliability Standards must establish clear and
reliable technical limits and capabilities for registered IBRs to
ensure that all registered IBRs are operated in a predictable and
reliable manner during normal operations and contingency event
conditions. The Reliability Standards must require that the operational
aspects of registered IBRs contribute towards meeting the overall
system needs for essential reliability services. The Reliability
Standards must include post-disturbance ramp rates and phase lock loop
synchronization requirements for registered IBRs.
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\15\ See, e.g., NERC, A Concept Paper on Essential Reliability
Services that Characterizes Bulk Power System Reliability, vi (Oct.
2014), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf</a> (Essential Reliability Services Concept
Paper) (listing the essential reliability services necessary to
maintain Bulk-Power System reliability).
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6. Pursuant to Sec. 39.2(d) of the Commission's regulations,\16\
we direct NERC to submit an informational filing within 90 days of the
issuance of the final action in this proceeding. NERC's filing shall
include a detailed and comprehensive standards development plan
explaining how NERC will prioritize the development of new or modified
Reliability Standards to meet the deadlines set forth in this final
action. We direct NERC to explain in its filing how it is prioritizing
its IBR Reliability Standard projects to meet the directives in this
final action, taking into account the risk posed to the reliability of
the Bulk-Power System, standard development projects already underway,
resource constraints, and other factors if necessary.
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\16\ 18 CFR 39.2(d) (the electric reliability organization shall
provide the Commission information as necessary to implement section
215 of the FPA).
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7. NERC's standards development plan must ensure that NERC submits
new or modified Reliability Standards by the following deadlines.
First, by November 4, 2024, NERC must submit new or modified
Reliability Standards that establish IBR performance requirements,
including requirements addressing frequency and voltage ride
through,\17\ post-disturbance ramp rates, phase lock loop
synchronization, and other known causes of IBR tripping or momentary
cessation.\18\ NERC must also submit, by November 4, 2024, new or
modified Reliability Standards that require disturbance monitoring data
sharing and post-event performance validation for registered IBRs.
Second, by November 4, 2025, NERC must submit new or modified
Reliability Standards addressing the interrelated directives
concerning: (1) data sharing for registered IBRs, unregistered IBRs,
and IBR-DERs in the aggregate; and (2) data and model validation for
registered IBRs, unregistered IBRs, and IBR-DERs in the aggregate.
Finally, by November 4, 2026, NERC must submit new or modified
Reliability Standards addressing planning and operational studies for
registered IBRs, unregistered IBRs, and IBR-DERs in the aggregate. We
continue to believe this staggered approach to standard development and
implementation is necessary based on the scope of work anticipated and
that specific target dates will provide a valuable tool and incentive
to NERC to timely address the directives in this final action.
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\17\ See Standardization of Generator Interconnection Agreements
& Procs., Order No. 2003, 104 FERC ] 61,103, at P 562 n.88 (2003)
(defining ride through as ``a Generating Facility staying connected
to and synchronized with the Transmission System during system
disturbances within a range of over- and under-frequency[/voltage]
conditions, in accordance with Good Utility Practice.'').
\18\ Momentary cessation is a mode of operation during which the
inverter remains electrically connected to the Bulk-Power System,
but the inverter does not inject current during low or high voltage
conditions outside the continuous operating range. As a result,
there is no current injection from the inverter and therefore no
active or reactive current (and no active or reactive power). NERC,
Reliability Guideline: BPS-Connected Inverter-Based Resource
Performance, 11 (Sept. 2018), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf</a> (IBR Performance
Guideline).
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8. Although we are not directing NERC to include implementation
dates in its informational filing and are leaving determination of the
appropriate effective dates to the standards development process, we
are concerned that the lack of a time limit for implementation could
allow identified issues to remain unresolved for a significant and
indefinite period. Therefore, we emphasize that industry has been aware
of and alerted to the need to address the impacts of IBRs on the Bulk-
Power System since at least 2016. The number of events, NERC Alerts,
reports, whitepapers, guidelines, and ongoing standards projects, as
discussed in more detail in section III and throughout this final
action, more than demonstrate the need for the expeditious
implementation of new or modified Reliability Standards addressing IBR
data sharing, data and model validation, planning and operational
studies, and performance requirements. Thus, in that light, the
Commission will take these issues into account when it considers the
proposed implementation plan for each new or modified Reliability
Standard when it is submitted for Commission. Further, as a general
matter, we believe that there is a need to have all the directed
Reliability Standards effective and enforceable well in advance of 2030
and direct NERC to ensure that the associated implementation plans
sequentially stagger the effective and enforceable dates to ensure an
orderly industry transition for complying with the IBR directives in
this final action prior to 2030.
II. Background
A. Section 215 of the FPA and the Mandatory Reliability Standards
9. Section 215 of the FPA provides that the Commission may certify
an
[[Page 74253]]
ERO, the purpose of which is to develop mandatory and enforceable
Reliability Standards, subject to Commission review and approval.\19\
Reliability Standards may be enforced by the ERO, subject to Commission
oversight, or by the Commission independently.\20\ Pursuant to section
215 of the FPA, the Commission established a process to select and
certify an ERO,\21\ and subsequently certified NERC.\22\
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\19\ 16 U.S.C. 824o(c).
\20\ Id. 824o(e).
\21\ Rules Concerning Certification of the Elec. Reliability
Org. & Procs. for the Establishment, Approval, & Enf't. of Elec.
Reliability Standards, Order No. 672, 114 FERC ] 61,104, order on
reh'g, Order No. 672-A, 114 FERC ] 61,328 (2006).
\22\ N. Am. Elec. Reliability Corp., 116 FERC ] 61,062, order on
reh'g and compliance, 117 FERC ] 61,126 (2006), aff'd sub nom.
Alcoa, Inc. v. FERC, 564 F.3d 1342 (D.C. Cir. 2009).
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10. Pursuant to section 215(d)(5) of the FPA, the Commission has
the authority, upon its own motion or upon complaint, to order the ERO
to submit to the Commission a proposed Reliability Standard or a
modification to a Reliability Standard that addresses a specific matter
if the Commission considers such a new or modified Reliability Standard
appropriate to carry out section 215 of the FPA.\23\ Further, pursuant
to Sec. 39.5(g) of the Commission's regulations, the Commission may
order a deadline by which the ERO must submit a proposed or modified
Reliability Standard.\24\
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\23\ 16 U.S.C. 824o(d)(5).
\24\ 18 CFR 39.5(g).
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B. Inverter-Based Resources
11. The Bulk-Power System generation fleet has traditionally been
composed almost exclusively of synchronous generation resources that
convert mechanical energy into electric energy through electromagnetic
induction. By virtue of the kinetic energy in their large rotating
components, these synchronous generation resources inherently resist
changes in system frequency, providing time for other governor controls
(when properly configured) to maintain supply and load balance.
Similarly, synchronous generation resources inherently provide voltage
support during voltage disturbances.
12. In contrast, IBRs do not use electromagnetic induction from
machinery that is directly synchronized to the Bulk-Power System.
Instead, the majority of installed IBRs use grid-following inverters,
which rely on sensed information from the grid (e.g., a voltage
waveform) to produce the desired AC real and reactive power output.\25\
Due to their inverters, IBRs can track grid state parameters (e.g.,
voltage angle) in milliseconds and react nearly instantaneously to
changing grid conditions. Some IBRs, however, are not configured or
programmed to support grid voltage and frequency in the event of a
system disturbance, and, as a result, will reduce power output,\26\
exhibit momentary cessation, or trip in response to variations in
system voltage or frequency.\27\ In other words, under certain
conditions some IBRs cease to provide power to the Bulk-Power System
due to how they are configured and programmed. Nonetheless, some models
and simulations incorrectly predict that some IBRs will ride through
disturbances, i.e., maintain real power output at pre-disturbance
levels and provide voltage and frequency support consistent with
Reliability Standard PRC-024-3 (Frequency and Voltage Protection
Settings for Generating Resources).\28\
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\25\ See, e.g., NERC, 2021 Long Term Reliability Assessment
Report, 6 (Dec. 2021), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf</a> (2021 LTRA Report)
(``IBRs respond to disturbances and dynamic conditions based on
programmed logic and inverter controls, not mechanical
characteristics.''); see also generally, Denholm et al., National
Renewable Energy Laboratory, Inertia and the Power Grid: A Guide
Without the Spin, NREL/TP-6120-73856, v (May 2020), <a href="https://www.nrel.gov/docs/fy20osti/73856.pdf">https://www.nrel.gov/docs/fy20osti/73856.pdf</a>.
\26\ NERC and WECC, San Fernando Disturbance, 2 (Nov. 2020),
<a href="https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf</a> (San Fernando Disturbance
Report) (covering the San Fernando event (July 7, 2020)).
\27\ See Essential Reliability Servs. & the Evolving Bulk-Power
Sys. Primary Frequency Response, Order No. 842, 162 FERC ] 61,128,
at P 19 (2018) (describing NERC's comment that increased IBR
deployment alongside retirement of synchronous generation resources
has contributed to the decline in primary frequency response); see
also NERC, Fast Frequency Response Concepts and Bulk Power System
Reliability Needs, 5 (Mar. 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf</a> (Fast Frequency Response White Paper) (explaining that as the
instantaneous penetration of IBRs with little or no inertia
continues to increase, system rate of change of frequency after a
loss of generation will increase and the time available to deliver
frequency responsive reserves will shorten, and illustrating the
steeper rate of change of frequency and the importance of speed of
response).
\28\ The NOPR referred to Reliability Standard PRC-024-2;
however, Reliability Standard PRC-024-3 became mandatory and
enforceable on October 1, 2022. Reliability Standards applicable in
the United States, both effective and retired, are available at
<a href="https://www.nerc.com/pa/Stand/Pages/USRelStand.aspx">https://www.nerc.com/pa/Stand/Pages/USRelStand.aspx</a>.
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13. IBRs across the Bulk-Power System exhibit common mode failures
that are amplified when IBRs act in the aggregate.\29\ Thus, both
localized and interconnection-wide IBR issues must be identified,
studied, and mitigated to preserve Bulk-Power System reliability.\30\
Although IBRs are typically smaller-megawatt (MW) facilities, they are
at greater risk than synchronous generation resources of ceasing to
provide power to the Bulk-Power System in response to a single fault on
the transmission or sub-transmission systems. Specifically, such
response can occur when individual IBR controls and equipment
protection settings are not configured to ride through system
disturbances.\31\ IBRs that enter momentary cessation may act in
aggregate and cause a reduction in power output far in excess of any
individual IBR's impact on the Bulk-Power System. The potential impact
of IBRs is not restricted by the size of a single facility or an
individual balancing authority area, but by the number of IBRs or
percent of generation made up by IBRs within a region. In areas of high
IBR penetration, this type of aggregate response may have an impact
much greater than the most severe single contingency (i.e., the
traditional worst-case N-1 contingency) \32\ of a balancing authority
area, potentially adversely affecting other balancing authority areas
within an interconnection.\33\ Unless
[[Page 74254]]
IBRs are configured and programmed to ride through normally cleared
transmission faults, the potential impact of losing IBRs individually
or in the aggregate will continue to increase as IBRs are added to the
Bulk-Power System and make up an increasing proportion of the resource
mix.
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\29\ NERC, An Introduction to Inverter-Based Resources on the
Bulk-Power System, 6 (June 2023), <a href="https://www.nerc.com/pa/Documents/2023_NERC_Guide_Inverter-Based-Resources.pdf">https://www.nerc.com/pa/Documents/2023_NERC_Guide_Inverter-Based-Resources.pdf</a> (explaining that ``NERC
continues to analyze large-scale grid disturbances involving common
mode failures in inverter-based resources that, if not addressed,
could lead to catastrophic events in the future'').
\30\ See NOPR, 181 FERC ] 61,125 at P 4.
\31\ See, e.g., NERC and WECC, 900 MW Fault Induced Solar
Photovoltaic Resource Interruption Disturbance Report, 19 (Feb.
2018), <a href="https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf">https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf</a> (Canyon 2 Fire Event Report) (covering the Canyon 2
Fire event (October 9, 2017)) (finding momentary cessation as a
major cause for the loss of IBRs when voltages rose above 1.1 per
unit or decreased below 0.9 per unit).
\32\ The most severe single contingency, or the N-1 contingency,
generally refers to the concept that a system must be able to
withstand an unexpected failure or outage of a single system
component and maintain reliable service at all times. See, e.g.,
NERC, Glossary of Terms Used in NERC Reliability Standards, 17 (Mar.
8, 2023), <a href="https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf">https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf</a> (NERC Glossary) (defining ``most severe single
contingency'').
\33\ See, e.g., San Fernando Disturbance Report at vi (stating
that ``[t]his event, as with past events, involved a significant
number of solar PV resources reducing power output (either due to
momentary cessation or inverter tripping) as a result of normally-
cleared [Bulk-Power System] faults. The widespread nature of power
reduction across many facilities poses risks to [Bulk-Power System]
performance and reliability.'').
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14. Simulations conducted by the NERC Resource Subcommittee
demonstrate that the risks to Bulk-Power System reliability posed by
momentary cessation are greater than any of the actual IBR disturbances
that NERC has documented since 2016.\34\ These simulations indicate the
potential for: (1) normally-cleared, three-phase faults at certain
locations in the Western Interconnection to result in upwards of 9,000
MW of solar PV IBRs entering momentary cessation across a large
geographic region; (2) transient instability caused by excessive
transfer of inter-area power flows during and after momentary
cessation; and (3) a drop in frequency that falls below the first stage
of under frequency load shedding in the Western Electricity
Coordinating Council (WECC) region (traditionally studied as the loss
of the two Palo Verde nuclear units in Arizona, which total
approximately 2,600 MW). These simulation results indicate that IBR
momentary cessation occurring in the aggregate can lead to instability,
system-wide uncontrolled separation, and voltage collapse.\35\
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\34\ See NERC, Resource Loss Protection Criteria Assessment,
(Feb. 2018), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf</a>.
\35\ Id. at 1-2, key findings 4, 7, 8.
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15. Although IBRs present risks that Bulk-Power System planners and
operators must account for, IBRs also present new opportunities to
support the grid and respond to abnormal grid conditions.\36\ When
appropriately programmed, IBRs can operate during greater frequency
deviations (i.e., a wider frequency range) than synchronous generation
resources.\37\ This operational flexibility--and the ability of IBRs to
perform with precision, speed, and control--could mitigate disturbances
on the Bulk-Power System. For Bulk-Power System operators to harness
the unique performance and control capabilities of IBRs, these
resources must be properly configured and programmed to support grid
voltage and frequency during normal and abnormal grid conditions and
must be accurately modeled and represented in transmission planning and
operations models.
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\36\ See, e.g., IBR Performance Guideline at vii (finding that
the power electronics aspects of IBRs ``present new opportunities in
terms of grid control and response to abnormal grid conditions.'').
\37\ See, e.g., Fast Frequency Response White Paper at 11.
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C. Notice of Proposed Rulemaking
16. On November 17, 2022, the Commission issued the NOPR in this
proceeding, proposing to direct NERC to submit new or modified
Reliability Standards addressing four gaps in the currently effective
Reliability Standards pertaining to IBRs: (1) data sharing; (2) model
validation; (3) planning and operational studies; and (4) performance
requirements.\38\ The Commission initiated this action in light of the
rapid change in the generation resource mix currently underway on the
Bulk-Power System and the projected addition of unprecedented numbers
of IBRs to the Bulk-Power System.\39\ The Commission noted that IBRs
provide many benefits, but that IBRs also present new considerations
for transmission planning and operation of the Bulk-Power System.\40\
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\38\ NOPR, 181 FERC ] 61,125 at P 1.
\39\ Id. P 2 (citing 2020 LTRA Report).
\40\ Id.
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17. The Commission proposed to direct NERC to address the four
reliability gaps by developing one or more new Reliability Standards or
modifying the currently effective Reliability Standards. The Commission
did not propose specific requirements; instead, the Commission
identified concerns that the Reliability Standards should address. The
Commission sought comments on its identified concerns and whether there
were other concerns related to planning for and integrating IBRs that
the Commission should direct NERC to address in this or a future
proceeding.\41\
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\41\ Id. P 6.
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18. First, the Commission proposed to direct NERC to develop new or
modified Reliability Standards addressing IBR data sharing. The
Commission proposed that the new or modified Reliability Standards
should ensure that NERC registered entities \42\ have the necessary
data to predict the behavior of all IBRs, including registered and
unregistered IBRs individually and in the aggregate, and IBR-DERs in
the aggregate, and their impact on the reliable operation of the Bulk-
Power System. The Commission stated that the new or modified
Reliability Standards should ensure that generator owners, transmission
owners, and distribution providers are required to share validated
modeling, planning, operations, and disturbance monitoring data for
registered and unregistered IBRs and IBR-DERs in the aggregate with
planning coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities.\43\
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\42\ NERC identifies and registers Bulk-Power System users,
owners, and operators who are responsible for performing specified
reliability functions to which requirements of mandatory Reliability
Standards are applicable. See NERC, Rules of Procedure, Section 500
(Organization Registration and Certification) (Aug. 25, 2022),
<a href="https://www.nerc.com/AboutNERC/RulesOfProcedure/NERC%20ROP%20effective%2020220825_with%20appendicies.pdf">https://www.nerc.com/AboutNERC/RulesOfProcedure/NERC%20ROP%20effective%2020220825_with%20appendicies.pdf</a>.
\43\ NOPR, 181 FERC ] 61,125 at P 5.
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19. Second, the Commission proposed to direct NERC to develop new
or modified Reliability Standards addressing IBR model validation. The
Commission proposed that the new or modified Reliability Standards
should ensure that IBR models are comprehensive, validated, and updated
in a timely manner, so that they can adequately predict the behavior of
registered and unregistered IBRs individually and in the aggregate, and
IBR-DERs in the aggregate, and their impacts on the reliable operation
of the Bulk-Power System.\44\
---------------------------------------------------------------------------
\44\ Id.
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20. Third, the Commission proposed to direct NERC to develop new or
modified Reliability Standards addressing IBR planning and operational
studies. The Commission proposed to direct that the new or modified
Reliability Standards ensure that validated IBR models are included in
transmission planning and operational studies to assess the reliability
impacts on Bulk-Power System performance by registered and unregistered
IBRs individually and in the aggregate, as well as IBR-DERs in the
aggregate. The Commission stated that the Reliability Standards should
ensure that planning and operational studies assess the impacts of
registered and unregistered IBRs individually and in the aggregate, and
IBR-DERs in the aggregate, within and across planning and operational
boundaries for normal operations and contingency event conditions.\45\
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\45\ Id.
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21. Fourth, the Commission proposed to direct NERC to develop new
or modified Reliability Standards addressing IBR performance
requirements.\46\ The Commission explained that the new or modified
Reliability Standards should require that registered IBRs provide
frequency and voltage support during frequency and voltage excursions,
including post-disturbance ramp rates and phase lock
[[Page 74255]]
loop synchronization, in a manner necessary to contribute toward
meeting the overall system needs for essential reliability
services.\47\ Further, the Commission stated that the new or modified
Reliability Standards should establish clear and reliable technical
limits and capabilities for registered IBRs to ensure that all
registered IBRs are operated in a predictable and reliable manner
during both normal operations and contingency event conditions.
---------------------------------------------------------------------------
\46\ Id.
\47\ Id. (citing Essential Reliability Services Concept Paper at
vi).
---------------------------------------------------------------------------
22. Finally, the Commission proposed to direct NERC to submit a
compliance filing within 90 days of the effective date of the final
action in this proceeding. The Commission proposed to direct NERC to
include in its compliance filing a detailed, comprehensive standards
development and implementation plan explaining how NERC will prioritize
the development and implementation of new or modified Reliability
Standards. The Commission stated that NERC should explain how it would
prioritize its IBR Reliability Standard projects to meet the directives
in the final action, taking into account the risk posed to the
reliability of the Bulk-Power System, standard development projects
already underway, resource constraints, and other factors if
necessary.\48\
---------------------------------------------------------------------------
\48\ Id. P 7.
---------------------------------------------------------------------------
23. The comment period for the NOPR ended on February 6, 2023, with
reply comments due on March 6, 2023. The Commission received 18 initial
comments and 3 reply comments.\49\
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\49\ A list of commenters to the NOPR and the abbreviated names
used in this final action appear in Appendix A. Interventions are
not necessary to file comments in a rulemaking. Nevertheless,
Acciona Energy USA Global LLC, Cordelio USA, Inc., Electricity
Consumers Resource Council, the Federal Energy Advocate, the Public
Utilities Commission of Ohio, Georgia Transmission Corporation,
GlidePath Development, LLC, Monitoring Analytics, LLC, and Old
Dominion Electric Cooperative filed motions to intervene.
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III. Need for Reform
24. As the Commission explained in the NOPR, a number of events
have demonstrated the challenges to transmission planning and
operations of the Bulk-Power System posed by gaps in the Reliability
Standards specific to IBRs.\50\ In this final action, we continue to
find that as the resource mix trends towards higher penetrations of
IBRs, the need to reliably integrate these resources into the Bulk-
Power System is expected to grow, and that the currently effective
Reliability Standards do not adequately address IBR reliability
risks.\51\ The continuing risks that the increasing penetration of IBRs
pose to the reliable operation of the Bulk-Power System underscore the
need for mandatory Reliability Standards to address these issues on a
nationwide basis.
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\50\ See NOPR, 181 FERC ] 61,125 at PP 24-26.
\51\ Id. PP 26-27.
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25. NERC, groups such as the Institute of Electrical and
Electronics Engineers (IEEE), and other entities have attempted to
address IBR-related reliability concerns at the manufacturer, state,
local, or individual entity level over the past several years.\52\
While the various ongoing IBR-related projects are important efforts,
the absence of a comprehensive plan to require that the increasing
numbers of IBRs are reliably interconnected, planned for, and operated
on the Bulk-Power System limits those individual projects' overall
impact. Moreover, these individual efforts could lead to inconsistent
results that fail to fully address the gaps identified herein, a
concern that could be resolved by addressing all IBR issues through the
Reliability Standards. Therefore, to help ensure that a broader range
of reliability concerns related to the impacts of IBRs on the Bulk-
Power System are addressed, that any necessary new requirements apply
nationwide, and that any new rules are mandatory, we find that it is
imperative for NERC to develop new or modified Reliability Standards as
directed in this final action to address reliability concerns related
to IBRs at all stages of interconnection, planning, and operations.
However, we note that the directives to NERC in this final action are
intended to complement other ongoing NERC and Commission actions to
address the impacts of all IBRs on the Bulk-Power System, as well as
existing voluntary efforts underway, and are not intended to supersede
or interfere with these efforts.
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\52\ For example, to address gaps in data and model validation
and to facilitate sharing and combining of neighboring planning
models, ISO New England (ISO-NE) has taken steps to retire obsolete
and unapproved models within its own footprint. See ISO-NE,
Generator Data Submittal Requirements--Planning, Topic Retiring
Obsolete and NERC Non-Approved Models, 121-125 (Jan. 24, 2023),
<a href="https://www.iso-ne.com/static-assets/documents/2023/01/20230124-gen-data-submittal-requirements-planning.pdf">https://www.iso-ne.com/static-assets/documents/2023/01/20230124-gen-data-submittal-requirements-planning.pdf</a>.
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A. Current Actions Are Insufficient To Address IBR Reliability Risks
26. As explained in the NOPR, at least 12 documented events on the
Bulk-Power System \53\ show IBRs acting unexpectedly and adversely in
response to normally cleared transmission line faults on the Bulk-Power
System, each highlighting one or more common mode failures of IBRs of
various sizes and voltage connection levels.\54\
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\53\ The 12 events report an average of approximately 1,000 MW
of IBRs entering into momentary cessation or tripping in the
aggregate. The 12 Bulk-Power System events are: (1) the Blue Cut
Fire (August 16, 2016); (2) the Canyon 2 Fire (October 9, 2017); (3)
Angeles Forest (April 20, 2018); (4) Palmdale Roost (May 11, 2018);
(5) San Fernando (July 7, 2020); (6) the first Odessa, Texas event
(May 9, 2021); (7) the second Odessa, Texas event (June 26, 2021);
(8) Victorville (June 24, 2021); (9) Tumbleweed (July 4, 2021); (10)
Windhub (July 28, 2021); (11) Lytle Creek (August 26, 2021); and
(12) Panhandle Wind Disturbance (March 22, 2022).
\54\ NOPR, 181 FERC ] 61,125 at P 4.
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27. In addition to those 12 documented events discussed in the
NOPR, on June 4, 2022, an IBR-related disturbance near Odessa, Texas
(the third in this location) occurred. During this disturbance, a
normally cleared single-line-to-ground fault resulted in a total loss
of 2,555 MW of synchronous and IBR generation, and system frequency
dropped to 59.7 Hz.\55\ This is the largest (to date) NERC-recorded
IBR-related disturbance event and the total loss of generation
resources was one and half times larger than the average loss of the 12
preceding reported events. The NERC and Texas Reliability Entity, Inc.
(Texas RE) joint report, issued in December 2022, explains that this
event is significant because the size of this disturbance nearly
exceeded the Texas Interconnection Resource Loss Protection Criteria
(i.e., 2,750 MW) defined in Reliability Standard BAL-003-2,\56\ which
is used to establish the largest credible contingency for frequency
stability in an interconnection.\57\
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\55\ A power system deviating from 60 Hz indicates there is a
generation and load imbalance. When the generation loss is too
large, automatic under-frequency load shedding is used to rebalance
the power system to prevent cascading failures that lead to
blackouts. In Texas, the automatic under-frequency load shed (UFLS)
program is set to trigger a sudden loss of load at 59.3 Hz. See
generally Public Utility Commission of Texas, Load Shed Protocols
for the Electric Reliability Council of Texas (ERCOT) Region, (Aug.
31, 2022), <a href="https://ftp.puc.texas.gov/public/puct-info/agency/resources/reports/leg/PUC_Load_Shed_Protocols_Study.pdf">https://ftp.puc.texas.gov/public/puct-info/agency/resources/reports/leg/PUC_Load_Shed_Protocols_Study.pdf</a>. See also
NERC Newsroom Announcement Odessa Disturbance Illustrates Need for
Immediate Industry Action on Inverter-Based Resources (Dec. 8,
2022), <a href="https://www.nerc.com/news/Headlines%20DL/OdessaDisturbance_08DEC22.pdf">https://www.nerc.com/news/Headlines%20DL/OdessaDisturbance_08DEC22.pdf</a> (explaining that ``[t]he 2022 Odessa
disturbance was a Category 3a event in the NERC Event Analysis
Process, and the combined loss of generation nearly exceeded the
Texas Interconnection Resource Loss Protection Criteria.'').
\56\ See Reliability Standard BAL-003-2 (Frequency Response and
Frequency Bias Setting), attach. A.
\57\ NERC and Texas RE, 2022 Odessa Disturbance, v (Dec. 2022),
<a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2022_Odessa_Disturbance_Report%20">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2022_Odessa_Disturbance_Report%20</a>(1).pdf (Odessa 2022
Disturbance Report) (covering events in Odessa, Texas on June 4,
2022).
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[[Page 74256]]
28. In response to the multiple Odessa, Texas disturbances, NERC
issued its third level 2 alert on IBR performance issues on March 14,
2023.\58\ In the alert, NERC states its level 2 alert is necessary
because the disturbances in Odessa, Texas, showed that solar PV IBR
resources exhibited ``systemic performance issues'' with the potential
to cause widespread outages on the Bulk-Power System.\59\ Although the
NERC alert pertains specifically to solar PV resources, the alert
recommendations may be applicable to Bulk-Power System connected
battery energy storage systems. Further, NERC explains that as the
penetration of Bulk-Power System-connected IBRs increases, it will be
necessary to address performance deficiencies in an ``effective and
efficient manner.'' \60\ In the March 2023 Alert, NERC sought to gather
information from registered generator owners of solar-PV (i.e., IBRs)
and to encourage them to implement recommendations to: (1) ensure
inverter protection settings, collector system settings, and substation
settings are updated or changed to mitigate inadvertent operations; and
(2) ensure that facility control modes, fault ride through modes and
parameters, and protections are set and coordinated to facilitate Bulk-
Power System voltage and frequency ride through.\61\
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\58\ NERC, Industry Recommendation: Inverter-Based Resource
Performance Issues (Mar. 2023), <a href="https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20R-2023-03-14-01%20Level%202%20-%20Inverter-Based%20Resource%20Performance%20Issues.pdf">https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20R-2023-03-14-01%20Level%202%20-%20Inverter-Based%20Resource%20Performance%20Issues.pdf</a> (March 2023
Alert).
\59\ See NOPR, 181 FERC ] 61,125 at P 18 (explaining that the
level 2 alerts recommend specific voluntary action to be taken by
registered IBRs).
\60\ March 2023 Alert at 1.
\61\ Id.
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29. NERC also recently issued another disturbance report covering
events in Southwest Utah in the morning of April 10, 2023.\62\ NERC
explains that the causes of the Southwest Utah disturbance are similar
to past solar PV IBR-related events.\63\ NERC identifies this event as
the ``first major widespread solar [PV] loss to occur in the Western
Interconnection outside of California.'' \64\
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\62\ NERC and WECC, 2023 Southwest Utah Disturbance (Aug. 2023),
<a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2023_Southwest_UT_Disturbance_Report.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2023_Southwest_UT_Disturbance_Report.pdf</a> (Southwest Utah
Disturbance Report).
\63\ Id. at iv.
\64\ Id.
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30. NERC has found that distributed energy resources' (i.e., IBR-
DERs') responses to Bulk-Power-System disturbances can cause short term
net load increases likely attributed to aggregate IBR-DERs
tripping.\65\ This behavior and the resulting net load increases can
impact Bulk-Power-System performance.\66\
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\65\ Multiple Solar PV Disturbances in CAISO: Disturbances
between June and August 2021 Joint NERC and WECC Staff Report, 17-
18, (Apr. 2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf</a>.
\66\ San Fernando Disturbance: Southern California Event: July
7, 2020 Joint NERC and WECC Staff Report, 12 (Nov. 2020), <a href="https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf</a>.
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31. NERC has also issued two recent IBR-related Reliability
Guidelines. In February 2023 NERC issued an updated guideline on
aggregate DER modeling (DER_A model),\67\ and in March 2023, NERC
issued its first guideline on electromagnetic transient (EMT) modeling
and studies for IBRs.\68\
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\67\ NERC, Reliability Guideline: Parameterization of the DER_A
Model for Aggregate DER (Feb. 2023), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_ModelingMerge_Responses_clean.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_ModelingMerge_Responses_clean.pdf</a> (2023 DER_A
Model Guideline). The DER_A model is the approved steady state and
dynamic model that industry has validated and maintained to model
IBR-DERs in the aggregate and used to study the potential impacts of
IBR-DERs in the aggregate on the Bulk-Power System. The term
``parameterize'' means to adjust the parameter values of a generic
model to best reflect the dynamic characteristics of a user-defined
model. The parameterization process aims at reducing the difference
(error) between the dynamic responses of both the generic and user-
defined models. See, e.g., Energy Systems Integration Group,
Parameterization, <a href="https://www.esig.energy/wiki-main-page/parameterization-d1/">https://www.esig.energy/wiki-main-page/parameterization-d1/</a>.
\68\ NERC, Reliability Guideline: Electromagnetic Transient
Modeling for BPS-Connected Inverter-Based Resources--Recommended
Model Requirements and Verification Practices (Mar. 2023), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline-EMT_Modeling_and_Simulations.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline-EMT_Modeling_and_Simulations.pdf</a> (EMT Modeling Guideline).
---------------------------------------------------------------------------
32. NERC also has nine separate projects underway to update its
currently effective Reliability Standards relevant to IBRs; however,
these projects are still in their early stages and, even if they are
completed, the results of these efforts may not fully address the
reliability risks that IBRs pose to the Bulk-Power System described
above.\69\
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\69\ The current NERC standards development projects underway
include: (1) Project 2021-04 (Modifications to PRC-002-2) to ensure
that disturbance monitoring data is available and provided by
generator owners of IBR facilities; (2) Project 2020-06
(Verifications of Models and Data for Generators) to enhance
requirements for model verification; (3) Project 2022-04 (EMT
Modeling) to address the inclusion of EMT modeling and studies in
relevant Reliability Standards; (4) Project 2022-02 (Modifications
to TPL-001-5.1 and MOD-032-1) addressing certain issues regarding
appropriate inclusion of IBRs and DERs in planning assessments; (5)
Project 2020-02 (Modifications to PRC-024 (Generator Ride-through))
to revise or replace current Reliability Standard PRC-024-3 with a
standard that will require ride through performance from all
generation resources; (6) Project 2023-02 (Performance of IBRs) to
address post-event performance validation ensuring that resources
perform the way they are expected or required to perform; (7)
Project 2021-01 (Modifications to MOD-025 and PRC-019) to ensure
that plant active and reactive power capabilities are accurately
provided to planning entities for use in studies; (8) Project 2021-
02 (Modifications to VAR-002-4.1) to clarify whether the generator
operator of a dispersed power resource must notify its associated
transmission operator upon a status change of a voltage controlling
device on an individual generating unit; and (9) Project 2023-01
(EOP-004 IBR Event Reporting) to ensure timely reporting of events
involving IBRs. See NERC, Reliability Standards Under Development,
<a href="https://www.nerc.com/pa/Stand/Pages/Standards-Under-Development.aspx">https://www.nerc.com/pa/Stand/Pages/Standards-Under-Development.aspx</a>.
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33. While we recognize NERC's ongoing efforts, systemic fault ride
through deficiencies continue to result in IBRs displaying unexpected
and abnormal performance during grid disturbances.\70\ In fact, in the
March 2023 Alert, NERC states that IBR-related issues continue to occur
and has announced plans to issue an alert by the end of 2023 regarding
IBR modeling issues.\71\
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\70\ March 2023 Alert at 6-7.
\71\ Id. at 6.
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34. The Commission has also been actively addressing ongoing IBR-
related concerns. Concurrently with the NOPR, the Commission issued an
order directing NERC to identify and register owners and operators of
unregistered IBRs that in the aggregate have a material impact on the
reliable operation of the Bulk-Power System.\72\ On February 15, 2023,
as amended on March 13, 2023, NERC submitted its compliance filing,
which included its work plan setting out NERC's planned activities and
milestones to register generator owners and operators of IBRs. On May
18, 2023, the Commission approved NERC's work plan and associated
implementation milestones.\73\
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\72\ See IBR Registration Order, 181 FERC ] 61,124 at P 6.
\73\ N. Am. Elec. Reliability Corp., 183 FERC ] 61,116 (2023)
(Order Approving Workplan). On August 16, 2023, NERC submitted its
first progress update on its registration workplan. See NERC,
Filing, Docket No. RD22-4-001 (filed Aug. 16, 2023).
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35. The Commission also recently revised the pro forma Large
Generator Interconnection Procedures (LGIP), the pro forma Large
Generator Interconnection Agreement (LGIA), the pro forma Small
Generator Interconnection Procedures (SGIP), and the pro forma Small
Generator Interconnection Agreement (SGIA) in Order No. 2023.\74\ Some
of those revisions address identified deficiencies
[[Page 74257]]
with respect to IBR modeling and ride through performance by requiring
that newly interconnecting non-synchronous generators (i.e., IBRs) (1)
submit accurate and verified models with a comparable level of accuracy
as synchronous generation resources and (2) configure or set control
and protection settings to ride through disturbances and continue to
support system reliability during abnormal frequency conditions and
voltage conditions within any physical limitations of the generating
facility.\75\
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\74\ See Improvements to Generator Interconnection Agreements &
Procs., Order No. 2023, 88 FR 61014 (Sept. 6, 2023), 184 FERC ]
61,054 (2023).
\75\ Id. PP 1661, 1715.
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36. In addition to NERC and Commission efforts, there are several
voluntary industry standards and manufacturer certification efforts
related to IBRs, such as the IEEE standard 2800-2022 \76\ for
transmission connected IBRs and IEEE standard 1547-2018 \77\ and
Underwriters Laboratory (UL) standard UL 1741 \78\ for distributed
energy resources. These efforts are intended to enhance the operating
performance and control capabilities of IBRs; however, these efforts do
not apply to all relevant IBRs and require adoption by state or other
regulatory authorities to become mandatory and enforceable.\79\
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\76\ IEEE, Standard for Interconnection and Interoperability of
Inverter-Based Resources (IBR) Interconnecting with Associated
Transmission Electric Power Systems (Apr. 22, 2022), <a href="https://standards.ieee.org/ieee/2800/10453/">https://standards.ieee.org/ieee/2800/10453/</a> (IEEE 2800-2022) (establishing
uniform technical minimum requirements for the interconnection,
capability, and performance of IBRs for reliable integration onto
the Bulk-Power System).
\77\ IEEE, Interconnection and Interoperability of Distributed
Energy Resources with Associated Electric Power Systems Interfaces
(Feb. 15, 2018), <a href="https://standards.ieee.org/ieee/1547/5915/">https://standards.ieee.org/ieee/1547/5915/</a> (IEEE
1547-2018). The IEEE 1547-2018 and more recent 2020 amendment (IEEE
1547a-2020) of this standard enhance operating performance and
control capabilities of IBR-DERs. For example, IBR-DERs compliant
with the IEEE standard will be equipped with the capability to ride
through voltage and frequency fluctuations in support of the
reliable operation of the Bulk-Power System.
\78\ UL Standard 1741 Edition 3, Inverters, Converters,
Controllers and Interconnection System Equipment for Use with
Distributed Energy Resources Scope, <a href="https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673">https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673</a>.
\79\ The IEEE Standards Association's board approved IEEE-2800-
2022 in September 2022. See IEEE, IEEE Standard for Interconnection
and Interoperability of Inverter-Based Resources (IBRs)
Interconnecting with Associated Transmission Electric Power Systems,
<a href="https://standards.ieee.org/ieee/2800/10453/">https://standards.ieee.org/ieee/2800/10453/</a> (explaining that IEEE-
2800-2022 establishes uniform technical minimum requirements for the
interconnection, capability, and lifetime performance of IBRs
interconnecting with transmission and sub-transmission systems in
North America). For IEEE-1547, states have made varied progress in
adopting the standard. See IEEE, IEEE Standard for Interconnection
and Interoperability of Distributed Energy Resources with Associated
Electric Power Systems Interfaces, <a href="https://sagroups.ieee.org/scc21/standards/1547rev/">https://sagroups.ieee.org/scc21/standards/1547rev/</a>; see also Odessa 2022 Disturbance Report at v
(explaining that the 2022 Odessa Disturbance ``is a perfect
illustration of the need for immediate industry action to ensure
reliable operation of the [Bulk-Power System] with increasing
penetrations of inverter-based resources.'').
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B. Existing Reliability Standards Do Not Adequately Address IBR
Reliability Risks
1. Data Sharing
37. The currently effective Reliability Standards do not require
owners and/or operators of registered IBRs, transmission owners that
have unregistered IBRs on their systems, or distribution providers that
have IBR-DERs on their systems to provide planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities with data that accurately
represents IBRs. Examples of needed data may include location;
capacity; telemetry; steady-state, dynamic, and short circuit modeling
information; control settings; ramp rates; equipment status; and
disturbance analysis data.\80\ Data that accurately represents IBRs is
necessary to properly plan for, operate, and analyze IBR performance on
the Bulk-Power System.\81\ Without data that accurately represents all
IBRs, planning coordinators, transmission planners, reliability
coordinators, transmission operators, and balancing authorities are not
able to develop system models that accurately account for the behavior
of IBRs on their system, nor are they able to facilitate the analysis
of Bulk-Power System disturbances.\82\
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\80\ NOPR, 181 FERC ] 61,125 at P 27.
\81\ NERC has provided examples of necessary planning and
operational IBR data. See, e.g., NERC, Industry Recommendation: Loss
of Solar Resources during Transmission Disturbances due to Inverter
Settings--II, 7-8 (May 2018), <a href="https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf">https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf</a> (Loss of Solar Resources Alert II) (describing examples
of planning and operational IBR data); NERC and Texas RE, Odessa
Disturbance, 20-21 (Sept. 2021), <a href="https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf</a> (Odessa 2021 Disturbance
Report) (covering events in Odessa, Texas on May 9, 2021 and June
26, 2021); see generally NERC and WECC, WECC Base Case Review:
Inverter-Based Resources (Aug. 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf</a> (Western Interconnection Base Case
IBR Review); NERC, Reliability Guideline: DER Data Collection for
Modeling in Transmission Planning Studies (Sept. 2020), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf</a> (IBR-DER
Data Collection Guideline).
\82\ NOPR, 181 FERC ] 61,125 at P 28.
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38. While Reliability Standard MOD-032-1 (Data for Power System
Modeling and Analysis), Requirement R2 requires generator owners to
submit modeling data and parameters to their transmission planners and
planning coordinators, it does not require generator owners to submit
registered IBR-specific modeling data and parameters such as control
settings for momentary cessation and ramp rates, which are necessary
for modeling steady state and dynamic registered IBR performance for
purposes of planning the Bulk-Power System.\83\ Nor does Reliability
Standard TOP-003-5 (Operational Reliability Data) require generator
owners to submit such registered IBR-specific modeling data and
parameters to their transmission operators or balancing
authorities.\84\
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\83\ See NERC, Technical Report, BPS-Connected Inverter-Based
Resource Modeling and Studies, 35 (May 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF&_IBR_Modeling_and_Studies_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF&_IBR_Modeling_and_Studies_Report.pdf</a> (Modeling and Studies Report)
(stating that Reliability Standard MOD-032-1 ``does not prescribe
the details that the modeling requirements must cover; rather, the
standard requirements leave the level of detail and data formats up
to each [transmission planner] and [planning coordinator] to
define.'') (footnote omitted).
\84\ See NOPR, 181 FERC ] 61,125 at P 29 (referring to
Reliability Standard TOP-003-4, the version of the standard
enforceable at that time. Reliability Standard TOP-003-5 became
mandatory and enforceable on April 1, 2023).
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39. Moreover, the currently effective Reliability Standards do not
ensure that Bulk-Power System planners and operators receive
disturbance monitoring data regarding all generation resources capable
of having a material impact on the reliable operation of the Bulk-Power
System, including registered IBRs. Such data is needed to adequately
assess disturbance events (e.g., a fault on the line) and the behavior
of IBRs during those events. Without adequate monitoring capability,
the disturbance analysis data for a system event is insufficient to
effectively determine the causes of the system event.\85\
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\85\ NERC and WECC, Multiple Solar PV Disturbances in CAISO, 13
(Apr. 2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf</a> (2021 Solar PV
Disturbances Report) (covering four events: Victorville (June 24,
2021); Tumbleweed (July 4, 2021); Windhub (July 28, 2021); and Lytle
Creek (August 26, 2021)) (explaining that the ``analysis team had
significant difficulty gathering useful information for root cause
analysis at multiple facilities . . . [and] this led to an
abnormally large number of `unknown' causes of power reduction for
the plants analyzed'').
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40. Limitations on the availability of event data have hampered
efforts by NERC, stakeholders, and industry to determine the causes of
various events since 2016. In many instances, data were limited and
disturbance monitoring equipment was absent because registered IBRs
interconnected at lower voltages and fell below the
[[Page 74258]]
MVA threshold.\86\ These IBRs therefore did not fall within the
thresholds of the currently effective Reliability Standard PRC-002-2
(Disturbance Monitoring and Reporting Requirements) Attachment 1
requirements for equipment installation.\87\ Further, the absence of
adequate monitoring capability leads to the potential for unreliable
operation of generation resources due to the inability to effectively
gather disturbance analysis data and develop mitigation strategies to
either avoid or recover from abnormal resource performance during
disturbance events in the future. While Reliability Standard PRC-002-2
requires the installation of disturbance monitoring equipment at
certain key nodes (e.g., stability limited interfaces), and such
limited placements have been adequate to provide the data necessary to
analyze major system events in the past, NERC has found that the
existing disturbance monitoring equipment is not sufficient (e.g., lack
of high speed data captured at the IBR or plant level controller and
low resolution time stamping of inverter sequence of event recorder
information) to analyze the widespread system events that have become
more common since 2016.\88\
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\86\ NERC, Improvements to Interconnection Requirements for BPS-
Connected Inverter-Based Resources, at 1 (Sept. 2019) (IBR
Interconnection Requirements Guideline) (reporting that the majority
of newly interconnecting IBRs are either connecting at voltages less
than 100 kV or with capacity less than 75 MVA and therefore do not
meet the size criteria in the bulk electric system definition).
NERC's Commission-approved bulk electric system definition is a
subset of the Bulk-Power System and defines the scope of the
Reliability Standards and the entities subject to NERC compliance.
Revisions to Electric Reliability Org. Definition of Bulk Elec. Sys.
& Rules of Proc., Order No. 773, 141 FERC ] 61,236 (2012) order on
reh'g, Order No. 773-A (May 17, 2013), 143 FERC ] 61,053 (2013),
rev'd sub nom. People of the State of N.Y. v. FERC, 783 F.3d 946 (2d
Cir. 2015); NERC Glossary at 7-9.
\87\ NOPR, 181 FERC ] 61,125 at P 32; see also Reliability
Standard PRC-002-2, Requirement R5.1.1 (specifying dynamic
disturbance recording data for generation resource(s) with gross
individual nameplate rating greater than or equal to 500 MVA, and
gross individual nameplate rating greater than or equal to 300 MVA
where the gross plant/facility aggregate nameplate rating is greater
than or equal to 1,000 MVA).
\88\ See NOPR, 181 FERC ] 61,125 at P 32 n.74 (citing NERC and
WECC, April and May 2018 Fault Induced Solar Photovoltaic Resource
Interruption Disturbances Report, 23 (Jan. 2019), <a href="https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf</a> (Angeles Forest and
Palmdale Roost Events Report) (covering the Angeles Forest (April
20, 2018) and Palmdale Roost (May 11, 2018) events and explaining
that the ``widespread nature of power reduction across many
facilities poses risks to [Bulk-Power System] performance and
reliability'' and finding that the ``lack of available high-speed
data at multiple inverter-based resources has hindered event
analysis''); San Fernando Disturbance Report at 7; Odessa 2021
Disturbance Report at 11; NERC, Odessa Disturbance Follow-up White
Paper (Oct. 2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf</a> (Odessa Disturbance White Paper)).
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41. The currently effective Reliability Standards do not require
Bulk-Power System planners and operators to receive modeling data and
parameters regarding unregistered IBRs that, individually or in the
aggregate, are capable of adversely affecting the reliable operation of
the Bulk-Power System. Further, the currently effective Reliability
Standards do not require that Bulk-Power System planners and operators
receive modeling data and parameters that accurately represent IBR-DERs
that in the aggregate have a material impact on the reliable operation
of the Bulk-Power System.\89\ As shown by various reports and
guidelines,\90\ Bulk-Power System planners and operators do not
currently have the data to accurately model the behavior of registered
and unregistered IBRs individually and in the aggregate, and IBR-DERs
in the aggregate, for steady-state, dynamic, and short circuit studies.
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\89\ See NOPR, 181 FERC ] 61,125 at P 80 (stating that
distribution providers should be permitted to provide IBR-DER
modeling data and parameters ``in the aggregate or equivalent for
IBR-DERs interconnected to their distribution systems (e.g., IBR-
DERs in the aggregate and modeled by resource type such as wind or
solar PV, or IBR-DERs in the aggregate and modeled by
interconnection requirements performance to represent different
steady-state and dynamic behavior.''); see also id. n.159
(explaining that for IBR-DERs ``a certain degree of simplification
may be needed either by model aggregation (i.e., clustering of
models with similar performance), by derivation of equivalent models
(i.e., reduced-order representation), or by a combination of the
two.'').
\90\ See, e.g., Commission Staff, Distributed Energy Resources
Technical Considerations for the Bulk Power System Staff Report,
Docket No. AD18-10-000, 11-13 (filed Feb. 15, 2018) (Commission
Staff IBR-DER Reliability Report) (explaining that, absent adequate
data, many Bulk-Power System models and operating tools will not
fully represent the effects of IBR-DERs in aggregate); see also IBR-
DER Data Collection Guideline at 2 (recommending that transmission
planners and planning coordinators update their data reporting
requirements for Reliability Standard MOD-032-1, Requirement R1 to
explicitly describe the requirements for aggregate IBR-DER data in a
manner that is clear and consistent with their modeling practices.
The IBR-DER Data Collection Guideline also recommended that
transmission planners and planning coordinators establish modeling
data requirements for steady-state IBR-DERs in aggregate and
coordinate with their distribution providers to develop these
requirements.).
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2. Data and Model Validation
42. Bulk-Power System planners and operators need accurate
planning, operations, and interconnection-wide models to ensure the
reliable operation of the Bulk-Power System. Bulk-Power System planners
and operators use electrical component models to build the generation,
transmission, and distribution facility models that they combine to
build their transmission area model. These models are further combined
with those of their neighbors to form the interconnection-wide models,
which are used to analyze the reliability of the interconnected
transmission system.\91\ Each of the planning, operations, and
interconnection-wide models consist separately of steady state,
dynamic, and short circuit models.
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\91\ See Reliability Standard MOD-033-2 (Steady-State and
Dynamic System Model Validation).
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43. Without planning, operations, and interconnection-wide models
that accurately reflect resource (e.g., generation and load) behavior
in steady state and dynamic conditions, Bulk-Power System planners' and
operators' system models \92\ are unable to adequately predict resource
behavior, including momentary cessation from both registered and
unregistered IBRs individually and in the aggregate, as well as IBR-
DERs in the aggregate, and their subsequent impacts on the Bulk-Power
System.\93\
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\92\ This final action uses the term ``system models'' to refer
collectively to planning and operations transmission area models and
interconnection-wide models.
\93\ See IBR Interconnection Requirements Guideline at 24
(stating that a systemic modeling issue was uncovered regarding the
accuracy of the IBR dynamic models submitted in the interconnection-
wide base cases following the issuance of the NERC Alert related to
the Canyon 2 Fire disturbance).
---------------------------------------------------------------------------
44. The currently effective Reliability Standards do not require
the use of NERC's approved component models; \94\ instead, models are
referred to generally in Reliability Standard MOD-032-1, Attachment
1.\95\ Without requirements to use approved component models in Bulk-
Power System planning and operations system models, resource
[[Page 74259]]
owners may provide modeling data that is based on a user-defined model
\96\ rather than an approved and industry-vetted model.\97\ The use of
user-defined models in system models can be problematic because their
internal model components cannot be viewed or modified, and thus they
produce outputs that cannot be readily explained or verified.\98\
Approved generator models that accurately reflect the generator
behavior in steady state and dynamic conditions are necessary for Bulk-
Power System planners and operators to adequately predict IBR behavior
and the subsequent impact of IBRs on the Bulk-Power System.\99\
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\94\ NERC, Libraries of Standardized Powerflow Parameters and
Standardized Dynamics Models version 1, 1 (Oct. 2015), <a href="https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf">https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf</a> (NERC
Standardized Powerflow Parameters and Dynamics Models) (explaining
that the NERC Modeling Working Group was tasked to develop,
validate, and maintain a library of standardized component models
and parameters for short-circuit, powerflow, and dynamics cases. The
standardized models in these libraries have documentation describing
their model structure, parameters, and operation. This information
has been vetted by the industry and thus deemed appropriate for
widespread use in planning, operations, and interconnection-wide
analysis.).
\95\ See Reliability Standard MOD-032-1, attach. 1 (explaining
that if a user-written model(s) is submitted in place of a generic
or library model, it must include the characteristics of the model,
including block diagrams, values, and names for all model
parameters, and a list of all state variables).
\96\ Some commenters use the term ``proprietary'' to describe
user-defined models. For purposes of this final action, the terms
``proprietary'' and ``user-defined'' models are synonymous. A user-
defined model is a unique manufacturer-specific model that does not
appear on the NERC approved component model list. In Order No. 2023,
the Commission defined a ``user-defined model'' as any set of
programming code created by equipment manufacturers or developers
that captures the latest features of controllers that are mainly
software-based and represents the entities' control strategies but
does not necessarily correspond to any particular generic library
model. See Order No. 2023, 184 FERC ] 61,054 at P 1660.
\97\ NERC Standardized Powerflow Parameters and Dynamics Models
at 1 (explaining that ``[s]ome of the model structures have
information that is considered to be proprietary or confidential,
which impedes the free flow of information necessary for
interconnection[hyphen]wide power system analysis and model
validation.''); see also NERC, Events Analysis Modeling Notification
Recommended Practices for Modeling Momentary Cessation Initial
Distribution, 1 n.4 (Feb. 2018), <a href="https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf">https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf</a> (explaining that more
detailed vendor-specific models may be used for local planning
studies; however, they are generally not allowed or recommended for
building interconnection-wide models).
\98\ See, e.g., EPRI, Model User Guide for Generic Renewable
Energy System, 2 (June 2015), <a href="https://www.epri.com/research/products/000000003002006525">https://www.epri.com/research/products/000000003002006525</a> (explaining that the ``models presented
here were developed primarily for the purpose of general public use
and benefit and to eliminate the long standing issues around many
vendor-specific models being proprietary and thus neither publicly
available nor easily disseminated among the many stakeholders.
Furthermore, using multiple user-defined non-standard models within
large interconnection studies, in many cases, presented huge
challenges and problems with effectively and efficiently running the
simulations.'').
\99\ NERC Standardized Powerflow Parameters and Dynamics Models
at 1 (explaining that there is a growing need for accurate
interconnection[hyphen]wide power flow and dynamics simulations that
analyze phenomena such as: frequency response, inter-area
oscillations, and interactions between the growing numbers of wide-
area control and protections systems).
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45. Any generation resource model's performance must be verified by
the generator owner using real-world data to confirm that the
generation resource model adequately reflects actual as-built settings,
historic performance, and/or field-testing data.\100\ The currently
effective Reliability Standards MOD-026-1 (Verification of Models and
Data for Generator Excitation Control System or Plant Volt/Var Control
Functions) \101\ and MOD-027-1 (Verification of Models and Data for
Turbine/Governor and Load Control or Active Power/Frequency Control
Functions) \102\ require each generator owner to verify models and data
for specific components of synchronous resources (e.g., generator
excitation control systems, plant volt/var control functions, turbine/
governor and load controls, and active power/frequency controls), but
they do not require a generator owner to provide verified models and
data for IBR-specific controls (e.g., power plant central controller
functions and protection system settings) to its transmission planner.
Additionally, the currently effective Reliability Standards neither
require the transmission owner for unregistered IBRs to provide
verified dynamic models nor require distribution providers to provide
verified dynamic models of IBR-DERs in the aggregate to their
transmission planners. Finally, the currently effective Reliability
Standards neither require the transmission owner for unregistered IBRs
nor the distribution providers for IBR-DERs in the aggregate to submit
the respective dynamic models to the applicable registered entities
that perform planning and operations functions.
---------------------------------------------------------------------------
\100\ Id. (explaining that the NERC Modeling Working Group was
tasked to develop, validate, and maintain a library of standardized
component models and parameters for powerflow and dynamics cases.
The standardized models in these libraries have documentation
describing their model structure, parameters, and operation. This
information has been vetted by the industry and thus deemed
appropriate for widespread use in interconnection[hyphen]wide
analysis).
\101\ See Reliability Standard MOD-026-1.
\102\ See Reliability Standard MOD-027-1.
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46. Once the generator owners for registered IBRs, transmission
owners for unregistered IBRs, and distribution providers for IBR-DERs
in the aggregate verify plant models, Bulk-Power System planners and
operators must validate and update system models (i.e., planning and
operation transmission area models as well as interconnection-wide
models) by comparing the provided data and resulting system models
against actual system operational behavior. While Reliability Standard
MOD-033-2 (Steady State and Dynamic System Model Validation) requires
validation using real-world data of the interconnection-wide
model,\103\ the currently effective Reliability Standards lack clarity
as to whether models of registered IBRs, unregistered IBRs, and IBR-
DERs in the aggregate are required to represent the real-world behavior
of the equipment installed in the field during interconnection-wide
disturbances that have exhibited common mode failures of IBRs.\104\
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\103\ Reliability Standard MOD-033-2, Requirements R1, R2.
\104\ NERC annually assesses the interconnection-wide model
quality and publishes a report to help entities responsible for
complying with Reliability Standard MOD-032 to resolve model issues
and improve the cases. NERC's 2021 Case Quality Metrics Assessment
indicates that planners are not able to develop accurate system
models (e.g., all interconnections demonstrate either a consistent
performance or worsening score in the unacceptable or not
recommended model metrics). See NERC, Case Quality Metrics Annual
Interconnection-wide Model Assessment, 26-29 (Oct. 2021), <a href="https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf">https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf</a>.
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47. Once Bulk-Power System planners and operators validate system
models,\105\ there must be additional requirements for generator
owners, transmission owners, and distribution providers to communicate
with Bulk-Power System planners and operators to ensure that any
changes to IBR settings, configurations, and ratings are updated.
Otherwise, the transmission system models will not adequately represent
the behavior of the actual installed equipment.\106\ While Reliability
Standards MOD-032-1 and MOD-033-2 include iterative updating and
validation processes, Reliability Standard MOD-032-1 does not require
IBR-specific modeling data and parameters, and Reliability Standard
MOD-033-2 does not contemplate the technology-specific performance
characteristics of registered IBRs, unregistered IBRs, and IBR-DERs in
the aggregate.
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\105\ This final action uses ``validation'' to mean the
confirmation that a model reflects real world operational behaviors
and uses ``verification'' to mean a model is properly parameterized
and validated.
\106\ See NOPR, 181 FERC ] 61,125 at P 39 n.91.
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48. Once Bulk-Power System planners and operators have validated
system models, Bulk-Power System planners and operators need to
coordinate with generator owners, transmission owners, and distribution
providers so that the system models adequately represent all generation
resources--including registered IBRs, unregistered IBRs, IBR-DERs in
the aggregate, and synchronous generation--as well as load. Reliability
Standards MOD-032-1 and MOD-033-2 do not require the applicable
entities to work collaboratively to create interconnection-wide models
that
[[Page 74260]]
accurately reflect the real-world interconnection-wide performance and
behavior of registered and unregistered IBRs individually and in the
aggregate, as well as IBR-DERs in the aggregate.\107\ As a result, the
models developed and deployed in compliance with these standards do not
contemplate that IBRs can reduce power, trip offline, or enter
momentary cessation individually or in the aggregate in response to a
single fault on a transmission or sub-transmission system.
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\107\ Reliability Standard MOD-032-1 is applicable to the
following registered entities: (1) balancing authorities, (2)
generator owners, (3) planning authorities/planning coordinators,
(4) load serving entity, (5) resource planners, (6) transmission
owners, (7) transmission planners, and (8) transmission service
providers. NERC has deregistered the load serving entity function
and has an ongoing standard drafting team project to replace this
function as an applicable entity in the Reliability Standards with
the distribution provider function. See Project-2022-02
Modifications to TPL-001 and MOD-032.
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3. Planning and Operational Studies
49. Once Bulk-Power System planners and operators have validated
registered IBR, unregistered IBR, and IBR-DER aggregate modeling and
operational data, the Reliability Standards must require that Bulk-
Power System planning and operational studies account for the actual
behavior of both registered IBRs and unregistered IBRs individually and
in the aggregate, as well as IBR-DERs in the aggregate. The Reliability
Standards do not require Bulk-Power System planning and operational
studies to assess the performance and behavior of both registered and
unregistered IBRs individually and in the aggregate (e.g., IBRs
tripping or entering momentary cessation individually or in the
aggregate), as well as IBR-DERs in the aggregate. Reliability Standard
TPL-001-5.1 (Transmission System Planning Performance Requirements)
requires planning coordinators and transmission planners to plan to
ensure reliable operations over a broad spectrum of system conditions
and following a wide range of probable contingencies, but it does not
require planning coordinators and transmission planners to assess the
performance and behavior of registered and unregistered IBRs
individually and in the aggregate, or IBR-DERs in the aggregate, during
normal and contingency conditions for the reliable operation of the
Bulk-Power System.\108\ NERC has stated that the currently effective
Reliability Standards do not mitigate the IBR reliability risks because
the IBR issues are not properly detected by models and studies.\109\
NERC has also found that there is an immediate need to enhance the
currently effective Reliability Standards. NERC explains that there is
a need to understand the extent of inverter performance risks and
modeling deficiencies as well as to gather necessary data for the
currently installed fleet.\110\
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\108\ Reliability Standard TPL-001-5.1 (Transmission System
Planning Performance Requirements) was approved by the Commission
and became effective on July 1, 2023. See N. Am. Elec. Reliability
Corp., Docket No. RD20-8-000 (June 10, 2020) (delegated letter
order) (approving a NERC-proposed erratum to Reliability Standard
TPL-001-5); Transmission Plan. Reliability Standard TPL-001-5, Order
No. 867, 170 FERC ] 61,030 (2020) (approving Reliability Standard
TPL-001-5).
\109\ See Odessa 2021 Disturbance Report at 43 (explaining that
``[p]lants are abnormally responding to [Bulk-Power System]
disturbance events and ultimately tripping themselves off-line.
These issues are not being properly detected by the models and
studies conducted during the generator interconnection study process
nor during annual planning assessments.'').
\110\ Odessa 2022 Disturbance Report at vii-ix.
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4. Performance Requirements
50. The currently effective Reliability Standards do not account
for the differences in response of registered IBRs and synchronous
generation resources during normal and contingency conditions. The
frequency of an interconnection depends on the instantaneous balance
between load and generation resources, to which all resources
contribute during both normal and contingency conditions. For frequency
to be maintained, generation resources must remain connected to the
grid and continue to support grid frequency (i.e., ride through) during
either loss of generation (underfrequency) or loss of load
(overfrequency) related frequency deviations. Reliability Standard PRC-
024-3 does not require registered IBRs (or any generator) to remain
connected to the Bulk-Power System and to continue to inject current
and support frequency inside the ``no trip zone.'' \111\ Therefore,
IBRs could continue to act adversely in response to normally cleared
faults by continuing to exhibit momentary cessation and power reduction
behaviors.
---------------------------------------------------------------------------
\111\ Reliability Standard PRC-024-3 is a voltage and frequency
protection settings standard that specifies that a generating
resource may neither trip nor enter momentary cessation (i.e., cease
injecting current) inside the boundaries of the frequency and
voltage excursion curves. The area inside the boundaries of the
frequency and voltage excursion curves is known as the ``no-trip
zone.'' See also Reliability Standard PRC-024-3, attach. 1, nn.8, 9.
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51. In addition, the currently effective Reliability Standards do
not require registered IBRs to continually inject current and support
voltage inside the ``no trip zone'' during a voltage excursion.\112\
The Reliability Standards also do not contain voltage ride through
performance requirements that address the unique protection and control
functions of registered IBRs that can cause tripping and momentary
cessation, even when the IBR voltage protection settings comply with
Reliability Standard PRC-024-3.
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\112\ The NOPR used both terms current and power when proposing
to direct NERC to develop new or modified Reliability Standards that
address registered IBRs' performance requirements. For clarity in
this final action, we only use ``current'' when directing NERC to
develop new or modified Reliability Standards that address
registered IBRs' performance requirements.
---------------------------------------------------------------------------
52. Finally, the currently effective Reliability Standards do not
require all generation resources that momentarily cease operation
following a system disturbance to return to pre-disturbance output
levels without impeded ramp rates or require that all generation
resources maintain voltage phase angle synchronization with the Bulk-
Power System grid voltage during a system disturbance. IBRs that lose
synchronization with grid voltage (i.e., phase lock loop loss of
synchronism) will momentarily cease current injection into the grid
during Bulk-Power System disturbance events due to protection and
control settings. Such momentary cessation occurrences exacerbate
system disturbances and have a material impact on the reliable
operation of the Bulk-Power System.\113\
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\113\ See NOPR, 181 FERC ] 61,125 at P 4.
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IV. Discussion
53. As discussed below, the Commission finds that the currently
effective Reliability Standards do not adequately address the risks
posed by the increasing numbers of IBRs connecting to the Bulk-Power
System. As noted by NERC in its initial comments, IBRs can introduce
significant risks to the Bulk-Power System if not integrated properly,
and NERC sees addressing such risks as a high priority for the
ERO.\114\ While NERC has initiated various projects to address aspects
of IBR reliability, we find that the actions we take in this final
action are necessary to maintain the reliable operation of the Bulk-
Power System. Accordingly, pursuant to section 215(d)(5) of the FPA, we
adopt the NOPR proposals with some modifications and direct NERC to
develop and submit new or modified Reliability Standards that address
the impacts of IBRs on the reliable operation of the Bulk-Power System.
Given the current and projected increase in the proportion of IBRs
within the
[[Page 74261]]
Bulk-Power System generation fleet, and for the reasons discussed in
section III above, we conclude that it is necessary to direct NERC to
develop new or modified Reliability Standards that address the
following specific matters: (1) generator owner data sharing for
registered IBRs, transmission owner data sharing for unregistered IBRs,
and distribution provider data sharing for IBR-DERs in the aggregate;
(2) data and model validation for registered and unregistered IBRs and
IBR-DERs in the aggregate; (3) planning and operational studies for
registered and unregistered IBRs individually and in the aggregate and
for IBR-DERs in the aggregate; and (4) registered IBR performance
requirements.
---------------------------------------------------------------------------
\114\ NERC Initial Comments at 2.
---------------------------------------------------------------------------
54. In directing the ERO to submit new or modified Reliability
Standards, we do not direct a specific method for addressing the
reliability concerns discussed herein. Rather, in this final action we
identify issues that should be addressed in the NERC standards
development process. Further, NERC has the discretion, subject to
Commission review and approval, as to how to address the reliability
concerns described below by developing one or more new Reliability
Standards or modifying currently effective Reliability Standards. We
direct NERC to develop new or modify the currently effective
Reliability Standards to address these issues and, when these
Reliability Standards are submitted to the Commission for approval, to
explain in the accompanying petition how the issues are addressed in
the proposed new or modified Reliability Standards. NERC may propose to
develop new or modified Reliability Standards that address our concerns
in an equally efficient and effective manner; however, NERC's proposal
should explain how the new or modified Reliability Standards address
the Commission's concerns discussed in this final action.\115\
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\115\ See, e.g., Order No. 693, 118 FERC ] 61,218 at PP 186,
297.
---------------------------------------------------------------------------
55. We modify the NOPR proposal and direct NERC to submit an
informational filing within 90 days of the issuance of the final action
in this proceeding that includes a detailed, comprehensive standards
development plan explaining how NERC will prioritize the development of
new or modified Reliability Standards to meet the deadlines set out
below, taking into account the risk posed to the reliability of the
Bulk-Power System, standard development projects already underway,
resource constraints, and other factors if necessary.
56. As discussed below, we are persuaded by commenters' suggestions
regarding the proposed staggered groupings for new or modified
Reliability Standards, and we modify the NOPR proposal to adopt NERC's
proposed staggered grouping that would result in NERC submitting new or
modified Reliability Standards in three stages.\116\ Therefore, in its
comprehensive standards development plan, NERC must submit new or
modified Reliability Standards by the following deadlines. First, by
November 4, 2024, NERC must submit new or modified Reliability
Standards that establish IBR performance requirements, including
frequency and voltage ride through, post-disturbance ramp rates, phase
lock loop synchronization, and other known causes of IBR tripping or
momentary cessation. NERC must also submit, by November 4, 2024, new or
modified Reliability Standards that require disturbance monitoring data
sharing and post-event performance validation for registered IBRs.
Second, by November 4, 2025, NERC must submit new or modified
Reliability Standards addressing the interrelated directives
concerning: (1) data sharing for registered IBRs, unregistered IBRs,
and IBR-DERs in the aggregate; and (2) data and model validation for
registered IBRs, unregistered IBRs, and IBR-DERs in the aggregate.
Finally, by November 4, 2026, NERC must submit new or modified
Reliability Standards addressing planning and operational studies for
registered IBRs, unregistered IBRs, and IBR-DER in the aggregate. NERC
may expedite its development plan and submit new or modified
Reliability Standards prior to the deadlines.
---------------------------------------------------------------------------
\116\ In the NOPR, the Commission proposed a staggered approach
that would result in NERC submitting new or modified Reliability
Standards in three stages. See NOPR, 181 FERC ] 61,125 at PP 8, 73.
In the final action, we are changing the content of the three
staggered filings.
---------------------------------------------------------------------------
57. While the NOPR proposed directing NERC to include
implementation dates (i.e., when the standards would become mandatory
and enforceable) in its standards development plan, we are persuaded by
NERC's comments that the implementation of new or modified Reliability
Standards is better determined through the NERC standards drafting
process. Therefore, we do not adopt the NOPR proposal to direct NERC to
include implementation dates in its standards development plan. Rather,
the Commission will consider the justness and reasonableness of each
new or modified Reliability Standard's implementation plan when it is
submitted for Commission approval.\117\ However, as discussed above,
the number of events, NERC Alerts, reports, whitepapers, guidelines,
and ongoing standards projects demonstrate the need for the expeditious
implementation of new or modified Reliability Standards addressing IBR
data sharing, data and model validation, planning and operational
studies, and performance requirements.\118\ Accordingly, the Commission
will take these issues into account when it considers the proposed
implementation plan for each new or modified Reliability Standard when
it is submitted to the Commission for review. Moreover, as a general
matter, we believe that there is a need to have all of the directed
Reliability Standards effective and enforceable well in advance of
2030, at which time IBRs are projected to account for a significant
share of the electric energy generated in the United States.\119\
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\117\ See Order No. 672, 114 FERC ] 61,104 at P 333 (``In
considering whether a proposed Reliability Standard is just and
reasonable, the Commission will consider also the timetable for
implementation of the new requirements, including how the proposal
balances any urgency in the need to implement it against the
reasonableness of the time allowed for those who must comply.'').
\118\ See supra P 7.
\119\ See, e.g., U.S. Energy Information Admin., Annual Energy
Outlook 2023 (Mar. 16, 2023), <a href="https://www.eia.gov/outlooks/aeo/narrative/index.php#TheElectricityMixinth">https://www.eia.gov/outlooks/aeo/narrative/index.php#TheElectricityMixinth</a> (projecting that
renewables will account for a significant portion of the electric
energy generated in the United States by 2030). The U.S. Energy
Industry Association defines the major types of renewable energy
sources to include resources such as biomass, hydropower,
geothermal, wind, and solar (e.g., Stirling cycle, solar PV, and
concentric solar). See <a href="https://www.eia.gov/energyexplained/renewable-sources/">https://www.eia.gov/energyexplained/renewable-sources/</a>. Of these resources, solar PV and wind generation
are IBRs.
---------------------------------------------------------------------------
58. We address below in further detail issues raised in the NOPR
and in comments regarding: (A) Commission authority to direct the ERO
to develop new or modified Reliability Standards under FPA section
215(d)(5); (B) data sharing, including registered IBR data, disturbance
monitoring data, unregistered IBR data, and data for IBR-DERs in the
aggregate; (C) data and model validation, including approved models,
dynamic model performance, validation of system models, and
coordination; (D) planning and operational studies; (E) performance
requirements; and (F) the informational filing and associated timeline
for Reliability Standard development.
A. Commission Authority To Direct the ERO To Develop New or Modified
Reliability Standards Under Section 215 of the FPA
59. In the NOPR, the Commission preliminarily found that the
currently
[[Page 74262]]
effective Reliability Standards do not adequately address the impacts
of IBRs on the reliable operation of the Bulk-Power System.\120\ The
NOPR stated that this constitutes a reliability gap in the areas of:
(1) data sharing; (2) model validation; (3) planning and operational
studies; and (4) performance requirements. To carry out section 215 of
the FPA, the NOPR proposed to direct NERC to develop and submit for
approval new or modified Reliability Standards that address IBRs and
their impacts on the reliable operation of the Bulk-Power System.
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\120\ NOPR, 181 FERC ] 61,125 at P 68.
---------------------------------------------------------------------------
1. Comments
60. NERC supports the Commission's efforts and agrees that the
currently effective Reliability Standards must be enhanced to address
the reliability risks posed by IBRs.\121\ Further, NERC and the
majority of commenters that responded on this topic generally support
the four topic areas for new or modified Reliability Standards (i.e.,
data sharing, model validation, planning and operational studies, and
performance requirements) that the Commission outlined in the
NOPR.\122\
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\121\ NERC Initial Comments at 7.
\122\ See, e.g., id.; AEP Initial Comments at 2; Bonneville
Initial Comments at 1; CAISO Initial Comments at 1; NYSRC Initial
Comments at 1.
---------------------------------------------------------------------------
61. Commenters agree that IBRs affect the reliable operation of the
Bulk-Power System and that some modifications to the currently
effective Reliability Standards are warranted.\123\ For example, IRC
states that IBRs may have an impact on the reliability of the Bulk-
Power System regardless of their size, registration status, or their
interconnection level (i.e., connected to transmission or
distribution).\124\ ACP/SEIA agree there is a need for clarity and
consistency for IBRs and their Reliability Standard obligations.\125\
EPRI states that its research and collaboration has shown that uniform
technical performance requirements, including ride through
requirements, can support system reliability.\126\ Indicated Trade
Associations agree that it is necessary to manage the impact of the
increase of IBRs on the Bulk-Power System through new or modified
Reliability Standards.\127\
---------------------------------------------------------------------------
\123\ See, e.g., AEU Initial Comments at 2 (agreeing the IBRs
may cause adverse reliability impacts and contribute reliability
benefits to the Bulk-Power System); InfiniRel Initial Comments at 1
(stating that ``[n]ew or modified Reliability Standards are
necessary to address the IBR-related reliability gaps'').
\124\ IRC Initial Comments at 2.
\125\ ACP/SEIA Initial Comments at 4.
\126\ EPRI Initial Comments at 4.
\127\ Indicated Trade Association Comments at 1.
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62. Ohio FEA, noting that the majority of IBR-related events
discussed in the NOPR predominantly took place in Texas and California,
defers to the Commission's findings regarding gaps in the currently
effective Reliability Standards for IBRs and emphasizes that it is the
Commission's role within its FPA section 215 authority to protect Bulk-
Power System reliability by directing NERC to develop new or modified
Reliability Standards.\128\ Nevertheless, Ohio FEA also notes that the
definition of ``Bulk-Power System'' does not include facilities used in
the local distribution of electric energy; and Ohio FEA emphasizes that
there is a dividing line between the Commission's authority over the
Bulk-Power System and its authority over its distribution system.\129\
Further, Ohio FEA cautions that there could be potential conflicts in
the reliability objectives, standards, and guidelines related to IBRs
on the transmission system versus the distribution system.\130\
---------------------------------------------------------------------------
\128\ Ohio FEA Initial Comments at 4.
\129\ Id. at 5.
\130\ Ohio FEA notes that transmission system operators prefer
generators to ride-through short duration transmission faults, while
distribution system operators typically prefer generators to trip
off during distribution faults. Ohio FEA Initial Comments at 6.
---------------------------------------------------------------------------
2. Commission Determination
63. We find that the directives in this final action are a valid
exercise of the Commission's authority pursuant to FPA section
215(d)(5). The plain language of the statute authorizes the Commission
to order the development of a Reliability Standard that ``addresses a
specific matter if the Commission considers such a new or modified
Reliability Standard appropriate to carry out this section.'' \131\
---------------------------------------------------------------------------
\131\ 16 U.S.C. 824o(d)(5).
---------------------------------------------------------------------------
64. We determine that directing NERC, as the ERO, to address the
specific matters pertaining to IBRs and their impact on the reliable
operation of the Bulk-Power System is appropriate to carry out FPA
section 215. As the NOPR stated, and as discussed in section III above,
there are multiple ERO findings of the reliability impacts of IBRs,
including guidelines, white papers, assessments, event reports, and
NERC Alerts, among others. Further, NERC has already begun efforts to
address IBR reliability issues through projects to improve the
mandatory Reliability Standards.\132\ As Bulk-Power System events
continue to occur and the risks that IBRs can pose to reliable
operation of the Bulk-Power System are demonstrated, there is an urgent
need to develop and implement mandatory Reliability Standards to
address these issues on a nationwide basis.
---------------------------------------------------------------------------
\132\ See supra P 32.
---------------------------------------------------------------------------
65. Section 215 of the FPA defines ``reliability standard'' as a
requirement to provide for reliable operation of the Bulk-Power
System.\133\ FPA section 215 defines ``reliable operation'' to mean
operating Bulk-Power System elements within their thermal, voltage, and
stability limits to prevent or avoid instability, uncontrolled
separation, or cascading failures as a result of a sudden disturbance,
including a cybersecurity incident, or unanticipated failure of system
elements.\134\ We are aware of the Commission's jurisdictional
boundaries as noted by Ohio FEA. Thus, the directives in this final
action are to NERC as the ERO to develop new or modified Reliability
Standards to require the reliable operation of the Bulk-Power System.
While certain directives pertain to registered entities such as
distribution providers obtaining aggregate data for IBR-DERs, the final
action does not impose any requirements on non-registered entities or
facilities used in the local distribution of electric energy.\135\
Regarding Ohio FEA's concerns about the need for coordination between
transmission system operators and distribution providers regarding
their different performance requirements,\136\ as the Commission has
explained, the IBR Registration Order and NERC's related work plan do
not address the registration of IBR-DERs.\137\ NERC has committed to
examine potential impacts of IBR-DERs on the reliable operation of the
Bulk-Power System; thus, we would expect that as a part of NERC's
communication plan it would consider how to address related
coordination issues between transmission operators and distribution
providers.\138\
---------------------------------------------------------------------------
\133\ 16 U.S.C. 824o(a)(3).
\134\ Id. 824o(a)(4).
\135\ Id. 824o(a)(1).
\136\ Ohio FEA notes that transmission system operators prefer
generators to ride-through short duration transmission faults, while
distribution system operators typically prefer generators to trip
off during distribution faults. Ohio FEA Initial Comments at 6.
\137\ See Order Approving Workplan, 183 FERC ] 61,116 at P 48
(citing IBR Registration Order, 181 FERC ] 61,124 at P 1 n.1
(stating that the order does not address IBRs connected to the
distribution system)). See also id. P 1 n.2 (citing 16 U.S.C.
824o(a)(1), which explains that the term ``Bulk-Power System'' does
not include facilities used in the local distribution of electric
energy).
\138\ See Id. P 15 (explaining that NERC's communication plan
outlines how NERC will coordinate with key stakeholders).
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[[Page 74263]]
B. Data Sharing
66. In the NOPR, the Commission preliminarily found that the
existing Reliability Standards are inadequate to ensure that sufficient
data of registered IBRs and unregistered IBRs, and data of IBR-DERs in
the aggregate, are provided to the registered entities responsible for
planning, operating, and analyzing disturbances on the Bulk-Power
System.\139\ The Commission observed that the currently effective
Reliability Standards, such as TOP-003-5 (Operational Reliability Data)
and IRO-010-4 (Reliability Coordinator Data Specification and
Collection),\140\ require the data recipient to specify a list of data
to be provided, and obligates other identified registered entities to
provide the specified data. The Commission preliminarily found that
these and other currently effective data-related Reliability Standards
do not require generator owners, generator operators, transmission
owners, and distribution providers to provide data that represents the
behavior of both registered and unregistered IBRs individually and in
the aggregate, as well as data of IBR-DERs in the aggregate, at a
sufficient level of fidelity for Bulk-Power System planners and
operators to accurately plan for, operate during, and analyze
disturbances on the Bulk-Power System.\141\
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\139\ NOPR, 181 FERC ] 61,125 at P 76.
\140\ Reliability Standard TOP-003-5 and Reliability Standard
IRO-010-4 became effective April 1, 2023.
\141\ NOPR, 181 FERC ] 61,125 at P 76.
---------------------------------------------------------------------------
67. To address this data sharing gap in the currently effective
Reliability Standards, the Commission proposed to direct NERC to
develop new or modified Reliability Standards that identify: (1) the
registered entities that must provide certain data of registered IBRs
and unregistered IBRs, as well as IBR-DER data in the aggregate; (2)
the recipients of that registered IBR, unregistered IBR, and IBR-DER in
the aggregate data; (3) the minimum categories or types of registered
IBR, unregistered IBR, and IBR-DER in the aggregate related data that
must be provided; and (4) the timing and periodicity for the provision
of registered IBR, unregistered IBR, and IBR-DER in the aggregate data
needed for modeling, operations, and disturbance analysis to the
appropriate registered entities and the review of that data by those
entities.\142\
---------------------------------------------------------------------------
\142\ Id. P 77.
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1. Registered IBR Data Sharing
68. In the NOPR, the Commission proposed to direct NERC to develop
new or modified Reliability Standards that require generator owners and
generator operators of registered IBRs to provide registered IBR-
specific modeling data and parameters (e.g., steady-state, dynamic, and
short circuit modeling information, and control settings for momentary
cessation and ramp rates) that accurately represents IBRs to their
planning coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities that are responsible
for planning and operating the Bulk-Power System.\143\ The Commission
explained that this approach would provide the registered entities
responsible for planning and operating the Bulk-Power System with
accurate data on registered IBRs.\144\
---------------------------------------------------------------------------
\143\ Id. P 78.
\144\ Id.
---------------------------------------------------------------------------
a. Comments
69. Commenters generally support the proposed directive to require
IBR generator owners and generator operators to provide registered IBR-
specific modeling data and parameters to planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities.\145\
---------------------------------------------------------------------------
\145\ See, e.g., NERC Initial Comments at 8; CAISO Initial
Comments at 24.
---------------------------------------------------------------------------
70. NERC states that poor or inadequate IBR data, models, and
information have proven to be a significant issue. For example,
generator owners may provide modeling data and information that is
generic or based on default parameters that do not reflect the as-built
facility.\146\ NERC states that providing adequate modeling data and
information is critical to create and maintain models that represent
necessary modeling data quality and accuracy, adding that data
accuracy, completeness, usability, and fidelity should be explicitly
defined, tested, and verified by all applicable entities, particularly
for modeling information used in reliability studies.\147\
---------------------------------------------------------------------------
\146\ NERC Initial Comments at 8.
\147\ Id. at 8-9.
---------------------------------------------------------------------------
71. Indicated Trade Associations and APS explain that the currently
effective Reliability Standards may not ensure that transmission
planners or operators have all necessary criteria and metrics to plan
for and reliably integrate certain IBRs on the Bulk-Power System.\148\
CAISO explains that its experience shows that modern IBRs are capable
of complying with data sharing and data and model validation
requirements.\149\ Further, CAISO supports national standards
establishing data sharing, and data and model validation guidelines, as
a patchwork approach would be inefficient (e.g., a significant number
of IBRs participating in the CAISO's markets are not bound by the
currently effective Reliability Standards and CAISO's standards do not
bind across the Western Electricity Coordinating Council).\150\
---------------------------------------------------------------------------
\148\ Indicated Trade Associations Initial Comments at 4-5; APS
Initial Comments at 2 (indicating it largely supports Indicated
Trade Associations Initial Comments but providing additional
comments on specific topics).
\149\ CAISO Initial Comments at 7.
\150\ Id. at 30-31.
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72. SPP states that it has heard from IBR owners that they have
concerns that some IBR data (and IBR-DER data) may be considered
proprietary by manufacturers and difficult to obtain. Nevertheless, SPP
contends that such concerns should not obstruct reliability
improvements and suggests that the final action should provide the
correct incentive for IBR owners to either use equipment that meets
data sharing requirements (i.e., equipment that is not proprietary) or
develop agreements or other protections for IBR data that is considered
proprietary.\151\
---------------------------------------------------------------------------
\151\ SPP Initial Comments at 2.
---------------------------------------------------------------------------
73. ACP/SEIA suggest modifying the directives to require generator
owners and operators to share IBR data. ACP/SEIA recommend that, rather
than mandating specific modeling and data submissions, planning
entities should have flexibility to identify the data they need for
their operations and planning activities, and that the new or modified
Reliability Standards should ensure that the data requested is
reasonable and necessary for improving reliability.\152\
---------------------------------------------------------------------------
\152\ ACP/SEIA Initial Comments at 11-12.
---------------------------------------------------------------------------
74. AEU and ACP/SEIA ask that, in addition to data provision
requirements for generator owners and operators, the Commission direct
NERC to specify data sharing requirements from transmission owners to
generator owners.\153\ For example, AEU explains that generator owners
and operators also require data from transmission owners to support
accurate modeling and performance, e.g., short circuit data, grid data
for offshore wind, information on other power electronic devices around
the IBR plant, and voltage harmonics.\154\ AEU adds that putting
requirements on transmission owners would be consistent with revisions
being developed for NERC's Modeling, Data, and Analysis (MOD)
Reliability Standards.\155\
---------------------------------------------------------------------------
\153\ AEU Initial Comments at 4; ACP/SEIA Initial Comments at
12-13.
\154\ AEU Initial Comments at 4.
\155\ Id. at 5.
---------------------------------------------------------------------------
75. ACP/SEIA, Mr. Plankey, and Ohio FEA raise security concerns and
the
[[Page 74264]]
need for accountability and protection of data sharing.\156\ Ohio FEA
recommends that NERC's Electricity Information Sharing and Analysis
Center (E-ISAC) could serve as a facilitator for IBR data sharing.\157\
---------------------------------------------------------------------------
\156\ ACP/SEIA Initial Comments at 12; Mr. Plankey Initial
Comments at 1; Ohio FEA Initial Comments at 9.
\157\ Ohio FEA Initial Comments at 9.
---------------------------------------------------------------------------
b. Commission Determination
76. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR
proposal and direct NERC to develop new or modified Reliability
Standards that require registered IBR generator owners and operators to
provide IBR-specific modeling data and parameters (e.g., steady-state,
dynamic, and short circuit modeling information, and control settings
for momentary cessation and ramp rates) that accurately represent the
registered IBRs to their planning coordinators, transmission planners,
reliability coordinators, transmission operators, and balancing
authorities that are responsible for planning and operating the Bulk-
Power System. As several commenters indicate, ensuring the sharing of
appropriate IBR modeling data is critical to create and maintain the
models used in reliability studies, and in turn to ensure that Bulk-
Power System transmission planners or operators are able to plan for,
operate, and reliably integrate IBRs onto the Bulk-Power System.
77. With regard to AEU and ACP/SEIA's comments that the Commission
direct NERC to specify data sharing requirements from transmission
owners to generator owners and operators, we believe that this request
may already be addressed through each transmission planner's existing
processes. For example, the New York Independent System Operator
(NYISO) and CAISO both have processes for obtaining such data after
demonstrating a need for the specific information requested and that
the required information protection and non-disclosure agreements are
signed.\158\ Nevertheless, to support accurate modeling and
performance, we direct NERC to consider during its standards
development process AEU and ACP/SEIA's suggested data sharing
requirements when developing the framework, criteria, and necessary
data exchange requirements to meet the registered IBR data sharing
directive.
---------------------------------------------------------------------------
\158\ See NYISO, What to expect when submitting a CEII Request
form (Sep. 9, 2021), <a href="https://nyiso.force.com/MemberCommunity/s/article/What-to-expect-when-submitting-a-CEII-Request-form">https://nyiso.force.com/MemberCommunity/s/article/What-to-expect-when-submitting-a-CEII-Request-form</a>; CAISO,
Application access, <a href="http://www.caiso.com/participate/Pages/ApplicationAccess/Default.aspx">http://www.caiso.com/participate/Pages/ApplicationAccess/Default.aspx</a> (explaining that the process for
secure planning and market systems data are available upon
compliance with the applicable submission instructions and submittal
of a non-disclosure agreement).
---------------------------------------------------------------------------
78. Commenters raised general concerns that mandating specific
modeling and data submissions would reduce the flexibility and
discretion of transmission planners and operators to identify the
information they need. We find that, given the need for IBRs to operate
in a predictable and reliable manner to ensure the reliable operation
of the Bulk-Power System, it is necessary to establish uniform, minimum
categories or types of data that must be provided so that Bulk-Power
System planners and operators can predict the behavior of all IBRs. As
discussed in more detail in section IV.C of this final action, we are
also directing NERC to develop new or modified Reliability Standards
that require the use of approved industry IBR models that accurately
reflect the behavior of all IBRs during steady state, short-circuit,
and dynamic conditions.
79. With regard to SPP's comment that some IBR data (and IBR-DER
data) may be considered proprietary (user-defined) by manufacturers and
difficult to obtain, we believe that the directives in this final
action should facilitate the provision of IBR data and address these
concerns further in the determination section IV.C.1 of this final
action.
80. The Commission did not propose in the NOPR to address new cyber
or physical security protections of IBRs beyond those in existing
applicable Reliability Standards. Therefore, while we decline to direct
NERC to develop IBR-specific cyber or physical security Reliability
Standards for IBRs in this effort, NERC should evaluate whether there
are gaps that must be addressed. We decline to direct that the NERC E-
ISAC facilitate all IBR data sharing, as these suggestions fall outside
the scope of this proceeding.
2. Disturbance Monitoring Data Sharing
81. In the NOPR, the Commission proposed to direct NERC to develop
new or modified Reliability Standards that include technical criteria
for disturbance monitoring equipment installed at buses and elements of
registered IBRs to ensure disturbance monitoring data is available to
Bulk-Power System planners and operators for analyzing disturbances on
the Bulk-Power System and to validate registered IBR models.\159\
---------------------------------------------------------------------------
\159\ NOPR, 181 FERC ] 61,125 at P 78.
---------------------------------------------------------------------------
a. Comments
82. NERC, ACP/SEIA, CAISO, Indicated Trade Associations, and NYSRC
support the proposed directive regarding disturbance monitoring
data.\160\ NERC agrees that disturbance monitoring data is fundamental
for model validation and post-event analysis activities, and to
identify reliability risks. NERC and Indicated Trade Associations both
point to NERC Project 2021-04 (Modifications to Reliability Standard
PRC-002-2), a NERC standard development project to modify disturbance
monitoring and reporting requirements so that Bulk-Power System-
connected IBRs are monitored in order to better assess
disturbances.\161\ NERC explains that the currently effective
Reliability Standard PRC-002-2 was originally written with synchronous
generation in mind, as that was the predominant form of generation in
use at the time.\162\ Thus, NERC explains that it is necessary to
update currently effective Reliability Standard PRC-002-2 so that it
requires registered IBRs to provide minimum disturbance monitoring data
\163\ to the planning coordinator or reliability coordinator, Regional
Entity, or NERC.
---------------------------------------------------------------------------
\160\ See NERC Initial Comments at 9; ACP/SEIA Initial Comments
at 12; CAISO Initial Comments at 39-40; Indicated Trade Associations
Initial Comments at 6; NYSRC Initial Comments at 2.
\161\ NERC Initial Comments at 9; Indicated Trade Associations
Initial Comments at 6.
\162\ See NERC Initial Comments at 9.
\163\ Disturbance monitoring data collection may include
sequence of events recording, digital fault recording, synchronized
phasor measurement unit recording, inverter oscillography recording
data, and inverter and plant-level fault codes.
---------------------------------------------------------------------------
83. CAISO encourages the Commission to direct NERC to consider
requiring IBRs to provide additional data, whether through telemetry
collections or other automated platform integrations, to enhance real-
time visibility of Bulk-Power System operations.\164\
---------------------------------------------------------------------------
\164\ CAISO Initial Comments at 40.
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84. ACP/SEIA agree with the proposed disturbance monitoring
directive but caution that there is a need to balance the burden to the
generator of collecting and providing the data with the benefit of that
data to reliability, e.g., requiring high-speed data collection from
every inverter at a plant is unnecessary because each inverter would
provide nearly identical data.\165\
---------------------------------------------------------------------------
\165\ ACP/SEIA Comments at 12.
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b. Commission Determination
85. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR
proposal to direct NERC to include in the new or modified Reliability
Standards technical criteria to require registered IBR generator owners
to install disturbance monitoring equipment at their buses
[[Page 74265]]
and elements, to require registered IBR generator owners to provide
disturbance monitoring data to Bulk-Power System planners and operators
for analyzing disturbances on the Bulk-Power System, and to require
Bulk-Power System planners and operators to validate registered IBR
models using disturbance monitoring data from installed registered IBR
generator owners' disturbance monitoring equipment.\166\ We agree with
NERC that updating Reliability Standard PRC-002-2 to apply to
registered IBRs for disturbance monitoring data collection, including
recording sequence of events, digital faults, synchronized phasor
measurements, inverter oscillography, inverter and plant-level fault
codes, and data retention, could be one way to accomplish this
directive. We further agree with the findings in NERC reports (e.g., a
lack of high-speed data captured at the IBR or plant-level controller
and low-resolution time stamping of inverter sequence of event recorder
information has hindered event analysis) and direct NERC through its
standard development process to address these findings.\167\
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\166\ See NERC, NERC Inverter-Based Resource Performance Task
Force (IRPTF)Review of NERC Reliability Standards White Paper, at 1
(Mar. 2020), <a href="https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf">https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf</a>
(explaining that PRC-002-2 should be revised to require disturbance
monitoring equipment in areas not currently contemplated by the
existing requirements, specifically in areas with potential
inverter-based resource behavior monitoring benefits); see also
Odessa Disturbance White Paper at 5 (explaining there are standard
features for modern inverters that should be enabled within IBR
plants to better understand their response to grid events and
improve overall fleet performance).
\167\ See supra note 88.
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86. As a general matter, we agree with ACP/SEIA regarding the need
to balance the burden to generator owners of collecting and providing
data collected by disturbance monitoring equipment with the benefit of
that data to reliability. Thus, in developing the directed data
collection requirements, we direct NERC to consider the burdens of
generators collecting and providing data, while assuring that Bulk-
Power System operators and planners have the data they need for
accurate disturbance monitoring and analysis.\168\ Likewise, regarding
CAISO's request that the Commission direct NERC to consider requiring
registered IBRs to provide additional data, we agree that such data
collections may be warranted, and direct NERC to consider through its
standards development process whether additional IBR data points (e.g.,
telemetry collections or other automated platform integrations) are
needed to further enhance real-time visibility of Bulk-Power System
operations.
---------------------------------------------------------------------------
\168\ See Order No. 693, 118 FERC ] 61,218 at P 188 (in
directing NERC to address or consider NOPR comments, the Commission
explained that it ``does not direct any outcome other than that the
comments receive consideration'').
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3. Unregistered IBR and IBR-DER Data Sharing
87. In the NOPR, the Commission preliminarily found that the
currently effective Reliability Standards do not ensure that Bulk-Power
System planners and operators receive modeling data and parameters
regarding unregistered IBRs that, individually or in the aggregate, are
capable of adversely affecting the reliable operation of the Bulk-Power
System. The Commission also preliminarily found that the currently
effective Reliability Standards do not require that Bulk-Power System
planners and operators receive modeling data and parameters regarding
IBR-DERs that in the aggregate are capable of adversely affecting the
reliable operation of the Bulk-Power System. The Commission
preliminarily determined that planning coordinators and other entities
need modeling data and parameters for both unregistered IBRs and IBR-
DERs in the aggregate to assure greater accuracy in modeling.\169\
---------------------------------------------------------------------------
\169\ NOPR, 181 FERC ] 61,125 at P 79.
---------------------------------------------------------------------------
88. The Commission proposed to direct NERC to submit new or
modified Reliability Standards addressing IBR data sharing that require
transmission owners to provide modeling data and parameters (e.g.,
steady-state, dynamic, and short circuit modeling information, and
control settings for momentary cessation and ramp rates) to appropriate
registered entities (e.g., planning coordinators, transmission
planners, reliability coordinators, transmission operators, and
balancing authorities) for unregistered IBRs in their transmission
owner areas where unregistered IBRs individually or in the aggregate
materially affect the reliable operation of the Bulk-Power System.\170\
The Commission similarly proposed to direct NERC to develop new or
modified IBR data sharing Reliability Standards that require
distribution providers to provide modeling data and parameters to
appropriate registered entities (e.g., planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities) for IBR-DERs in the aggregate
connected in their distribution provider areas where those IBR-DERs in
the aggregate materially affect the reliability of the Bulk-Power
System and are not otherwise subject to compliance with Reliability
Standards.\171\
---------------------------------------------------------------------------
\170\ Id.
\171\ Id. (citing NERC, Reliability Guideline: Parameterization
of the DER_A Model, 8-16 (Sept. 2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf</a> (2019 DER_A Model
Guideline) (retired)).
---------------------------------------------------------------------------
89. The Commission stated that this approach would be similar to
that taken in other Reliability Standards that require transmission
owners and distribution providers to provide certain planning and
operational data received from unregistered entities to appropriate
registered entities (e.g., planning coordinators, transmission
planners, reliability coordinators, transmission operators, and
balancing authorities).\172\ The Commission recognized that, given the
small size and location of many of the IBR-DERs on the distribution
system, it may not be practical for distribution providers to provide
modeling data and parameters to model individual IBR-DERs
directly.\173\ The Commission instead proposed that the new or modified
Reliability Standards should permit distribution providers to provide
modeling data and parameters of IBR-DERs in the aggregate or equivalent
for IBR-DERs interconnected to their distribution systems (e.g., IBR-
DERs in the aggregate and modeled by resource type such as wind or
solar PV, or IBR-DERs in the aggregate and modeled by interconnection
requirements performance to represent different steady-state and
dynamic behavior) to appropriate registered entities (i.e., planning
coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities).\174\
---------------------------------------------------------------------------
\172\ Id. P 80 (noting that this approach is consistent with
certain currently effective Reliability Standards and citing
Reliability Standard IRO-010-2 (Reliability Coordinator Data
Specification and Collection), Requirement R1 (providing that
``[t]he Reliability Coordinator shall maintain a documented
specification for the data . . . including non-[bulk electric
system] data''(emphasis added)), Requirement R2 (providing that
``[t]he Reliability Coordinator shall distribute its data
specification to entities''), Requirement R3 (providing that
``[e]ach . . . Transmission Owner, and Distribution Provider
receiving a data specification in Requirement R2 shall satisfy the
obligations of the documented specifications''); Reliability
Standard PRC-006-3 (Automatic Underfrequency Load Shedding),
Requirement R8 (requiring that a UFLS entity, i.e., relevant
transmission owner and distribution provider, ``provide data to its
Planning Coordinator(s)'')). Reliability Standard IRO-010-4
(Reliability Coordinator Data Specification and Collection) became
effective April 1, 2023; Reliability Standard PRC-006-5 (Automatic
Underfrequency Load Shedding) became effective April 1, 2021.
\173\ Id.
\174\ Id. (citing NERC, Distributed Energy Resources: Connection
Modeling and Reliability Considerations, 7 (Feb. 2017), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf</a> (NERC DER Report); 2019
DER_A Model Guideline).
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[[Page 74266]]
a. Comments
90. Commenters generally support the NOPR's proposed directive to
require transmission owners to collect and share unregistered IBR data
and to require distribution providers to collect and share modeling
data and parameters of IBR-DERs in the aggregate.\175\ However, several
commenters raise concerns that transmission owners and distribution
providers may not be able to collect all the requested data.\176\
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\175\ See generally NERC Initial Comments at 9; AEU Initial
Comments at 5; ACP/SEIA Initial Comments at 11-12 (although
cautioning against mandating specific modeling and data submissions
to allow entities to identify and request the data and modeling that
best meets their needs); IRC Initial Comments at 2-3; ISO-NE Initial
Comments at 2; NYSRC Initial Comments at 2; Ohio FEA Initial
Comments at 2, 9.
\176\ See AEP Initial Comments at 4; APS Initial Comments at 4;
Trade Associations Initial Comments at 11-12; and SCE/PG&E Initial
Comments at 10-11.
---------------------------------------------------------------------------
91. NERC, AEU, IRC, and ISO-NE support the Commission's directive
to revise the currently effective Reliability Standards to require that
adequate and accurate data is available for all Bulk-Power System-
connected resources (including unregistered IBRs).\177\ NERC notes that
experience has demonstrated that, without all of the relevant
protections and controls being modeled and validated, the resulting
interconnection and long-term planning studies will not identify
possible performance issues.\178\ NERC recommends that if no
distribution provider is registered on a specific system, the
transmission owner should coordinate with the relevant transmission
planner, planning coordinator, balancing authority, transmission
operator, and/or reliability coordinator for developing, submitting,
and validating aggregate DER models (inclusive of IBR-DER) in planning
or operational studies.\179\
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\177\ NERC Initial Comments at 9; AEU Initial Comments at 4, 7;
IRC Initial Comments at 2; ISO-NE Initial Comments at 2.
\178\ NERC Initial Comments at 13.
\179\ Id.
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92. IRC also supports Reliability Standards that facilitate the
provision of IBR-related data from registered entities to reliability
coordinators, planning coordinators, and other registered entities
responsible for the safe and reliable operation of the Bulk-Power
System.\180\ To ensure the appropriate data is provided, IRC requests
that the final rule specify the data to be submitted by all types of
IBRs (i.e., registered IBRs, unregistered IBRs, and IBR-DERs in the
aggregate) and transmission devices using similar technologies.\181\
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\180\ IRC Initial Comments at 2.
\181\ Id. at 3.
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93. ISO-NE supports the Commission's proposed directive and asserts
that, for smaller IBR-DERs, distribution providers are in the best
position to provide aggregate models that include behind-the-meter
resources.\182\ ISO-NE notes that, in the absence of this aggregate
data, it uses assumptions based on industry documents and benchmarking
to actual events, which may not always reflect the realities of
IBRs.\183\ Ohio FEA supports the Commission's proposals and states that
the lack of visibility into operating assets behind the meter,
including ride through of IBR-DERs, is an ongoing issue.\184\
---------------------------------------------------------------------------
\182\ ISO-NE Reply Comments at 2, 5.
\183\ ISO-NE Initial Comments at 2.
\184\ Ohio FEA Initial Comments at 2, 9.
---------------------------------------------------------------------------
94. AEU states that distribution providers are best situated to
fulfill Reliability Standard requirements related to the aggregate
impact of IBR-DERs and cautions against any direct assignment of
responsibility to owners or operators of individual IBR-DERs.\185\
---------------------------------------------------------------------------
\185\ AEU Initial Comments at 7.
---------------------------------------------------------------------------
95. CAISO, Indicated Trade Associations, and SPP generally support
the proposed directive but caution that transmission owners and
distribution providers should only be required to collect and share
information that they can reasonably obtain, and that certain data may
be difficult to obtain.\186\ CAISO encourages the Commission to direct
NERC to address the potential ``compliance trap'' and suggests that if
the Commission is going to shift the compliance burden to transmission
owners and distribution providers from the IBR generator owner or
operator, there should be consistent mechanisms in place for
transmission owners and distribution providers to receive such
information.\187\
---------------------------------------------------------------------------
\186\ CAISO Initial Comments at 31; Indicated Trade Associations
Initial Comments at 9; SPP Initial Comments at 2.
\187\ CAISO Initial Comments at 32, 38.
---------------------------------------------------------------------------
96. APS, AEP, LADWP, and SCE/PG&E raise concerns with the proposed
directive requiring transmission owners to collect and share
unregistered IBR data and distribution providers to collect and share
IBR-DER data due to the lack of mechanisms or leverage in place to
require the provision of the underlying data from unregistered
entities.\188\ For example, AEP explains that it does not have access,
as a transmission owner, to all of the data necessary to model the
behavior of unregistered IBRs, nor does it have access, as a
distribution provider, to all the data needed to accurately model IBR-
DERs in the aggregate.\189\
---------------------------------------------------------------------------
\188\ APS Initial Comments at 4; AEP Initial Comments at 2;
LADWP Reply Comments at 2; SCE/PG&E Initial Comments at 6.
\189\ AEP Initial Comments at 4.
---------------------------------------------------------------------------
97. SCE/PG&E contend that it is inappropriate for NERC to develop
new Reliability Standards that place a compliance burden on
transmission owners and distribution providers for unregistered IBRs
and IBR-DERs in the aggregate. SCE/PG&E explain that transmission
owners and distribution providers would not have the requisite
information to comply with the Reliability Standards and that the
transmission owners and distribution providers would need to develop
new procedures and provide oversight and enforcement for unregistered
IBRs and IBR-DERs. SCE/PG&E further state that balancing authorities,
rather than transmission owners and/or distribution providers, should
be held responsible for oversight and enforcement as they have the
greatest visibility into the operation of IBRs on the grid.\190\
---------------------------------------------------------------------------
\190\ SCE/PG&E Initial Comments at 6-7.
---------------------------------------------------------------------------
98. APS suggests alternatives to the proposed IBR-DER directive.
APS has concerns with the proposal to require distribution providers to
share information provided by an unregistered entity because the IBR-
DER customer may be unable or unwilling to provide the data
voluntarily.\191\ Therefore, APS recommends that the Commission not
direct NERC to require distribution providers to collect and share IBR-
DER data, but instead defer to the stakeholder process during the
standards development process to determine who will provide the data,
how the aggregate IBR-DER model will be developed, and how the model
will be validated.\192\
---------------------------------------------------------------------------
\191\ APS Initial Comments at 4.
\192\ Id. at 4.
---------------------------------------------------------------------------
99. APS and Indicated Trade Associations oppose a directive
requiring transmission owners and distribution providers to collect and
share data from unregistered IBRs and IBR-DERs in the aggregate.
Indicated Trade Associations emphasize that, while it may be
appropriate to specify the types of data to be submitted, a registered
entity cannot provide data that the registered entity itself does not
have and has no ability to collect.\193\
[[Page 74267]]
APS believes that the unregistered IBRs and IBR-DERs may be unable or
unwilling to provide the data voluntarily and consistently, and that
transmission owners will have little to no leverage to compel delivery
of data from the unregistered entities; thus, these requirements are
more effectively shouldered by the IBR owners.\194\ Indicated Trade
Associations explain that, in most if not all cases, a transmission
owner or distribution provider has only the information provided to it
during the interconnection approval process and interconnection
agreements may not require the IBRs to provide modeling data. Indicated
Trade Associations explain that in such a case, transmission owners and
distribution providers may not have the contractual right to add
requirements to provide data unilaterally and retroactively. In
addition, Indicated Trade Associations clarify that some IBR-DERs on
the distribution system interconnect under utility retail tariffs
without a separate interconnection agreement. Indicated Trade
Associations aver that transmission owners and distribution providers
should not be held responsible for an unregistered IBR owner that does
not or cannot provide the data, and that any directives regarding
unregistered IBR and IBR-DER data sharing and model validation should
recognize this limitation.\195\
---------------------------------------------------------------------------
\193\ Indicated Trade Associations Initial Comments at 10.
\194\ APS Initial Comments at 4.
\195\ Indicated Trade Associations Initial Comments at 10-13.
---------------------------------------------------------------------------
100. Alternatively, Indicated Trade Associations propose that the
Commission could either convene a forum to consider the benefits of
applying the new Reliability Standards to distribution providers with
IBR-DERs in their footprints, or direct NERC to submit a study on the
challenges for development and implementation of those new or modified
Reliability Standards. Indicated Trade Associations also support NERC's
request for flexibility in determining appropriate requirements with
respect to collecting and modeling IBR-DER data. In the alternative,
Indicated Trade Associations ask the Commission to limit the
obligations shouldered by the distribution providers to what is
feasible.\196\
---------------------------------------------------------------------------
\196\ Id. at 9, 12-13.
---------------------------------------------------------------------------
101. Indicated Trade Associations recommend giving consideration to
collecting data from existing registered generator owners and operators
that also own some IBR-DERs.\197\
---------------------------------------------------------------------------
\197\ Id. at 2.
---------------------------------------------------------------------------
b. Commission Determination
102. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR
proposal, with modification. Specifically, as proposed in the NOPR, we
direct NERC to submit to the Commission for approval one or more new or
modified Reliability Standards that require: (1) transmission owners to
provide to Bulk-Power System planners and operators modeling data and
parameters for unregistered IBRs in their transmission owner areas
that, individually or in the aggregate, materially affect the reliable
operation of the Bulk-Power System and (2) distribution providers to
provide to Bulk-Power System planners and operators modeling data and
parameters for IBR-DERs in the aggregate in their distribution provider
areas where the IBR-DERs in the aggregate materially affect the
reliable operation of the Bulk-Power System.\198\
---------------------------------------------------------------------------
\198\ See supra note 14 (noting that although the remaining
subset of unregistered IBRs and IBR-DERs in the aggregate will not
be subject to the mandatory and enforceable Reliability Standards
set forth herein, they may be subject to provision of data and
information to their respective transmission owners and distribution
providers, as applicable, in accordance with their specific
interconnection agreements; and encouraging NERC to continue its
efforts to review and evaluate whether reliability gaps continue to
remain and if new or modified functional registration categories or
Reliability Standards are necessary).
---------------------------------------------------------------------------
103. However, we find persuasive the comments explaining that
certain data may be challenging or infeasible for the transmission
owner or distribution provider to obtain.\199\ We recognize that there
may be limitations on the ability of certain transmission owners to
provide all data about unregistered IBRs that Bulk-Power System
transmission planners and operators may need for the reliable operation
of the Bulk-Power System. Likewise, there may be limitations on the
ability of certain distribution providers to provide all data about
IBR-DERs in the aggregate that Bulk-Power System transmission planners
and operators may need for the reliable operation of the Bulk-Power
System. We therefore modify the NOPR proposal, as discussed below.
---------------------------------------------------------------------------
\199\ See, e.g., AEP Initial Comments at 2; APS Initial Comments
at 4; Indicated Trade Associations Initial Comments at 10; SCE/PG&E
Initial Comments at 6, 7.
---------------------------------------------------------------------------
104. Recognizing that there may be instances in which transmission
owners are unable to gather adequate unregistered IBR modeling data and
parameters to create and maintain unregistered IBR models in their
transmission owner areas, we modify the NOPR proposal and direct NERC
to develop new or modified Reliability Standards that require each
transmission owner, if unable to gather accurate unregistered IBR data
or unable to gather unregistered IBR data at all, to provide instead to
the Bulk-Power System planners and operators in their areas: (1) an
estimate of the unregistered IBR modeling data and parameters, (2) an
explanation of the limitations of the availability of data, (3) an
explanation of the limitations of any data provided by unregistered
IBRs, and (4) the method used for estimation. We believe that this
directive appropriately balances commenters' concerns about data
accessibility and burden with the established need for transmission
owners to provide unregistered IBR modeling data and parameters to
Bulk-Power System planners and operators in their transmission owner
area. We recognize that estimated modeling data and parameters are
approximations of actual modeling data and parameters. We further
acknowledge that there is some degree of error in estimated modeling
data and parameters. However, on balance we believe that requiring such
estimates with explanation of any limitations is an improvement from
not having any data at all; and that even estimates will increase the
overall adequacy of models and improve the reliability of the Bulk-
Power System. To support this data collection, we further direct NERC
to consider commenters suggestions to implement a process or mechanism
by which transmission owners would receive modeling data and
parameters.\200\
---------------------------------------------------------------------------
\200\ See, e.g., AEP Initial Comments at 2; SCE/PG&E Initial
Comments at 6-7.
---------------------------------------------------------------------------
105. We also recognize that there may be instances where
distribution providers are similarly unable to gather adequate modeling
data and parameters from IBR-DERs.\201\ Accordingly, to account for
instances in which distribution providers are unable to gather adequate
modeling data and parameters of IBR-DERs to create and maintain IBR-DER
models, we modify the NOPR proposal and direct NERC to develop new or
modified Reliability Standards that require that each distribution
provider, if unable to gather accurate IBR-DERs data in the aggregate
or unable to gather IBR-DERs data in the aggregate at all, provide
instead to
[[Page 74268]]
the Bulk-Power System planners and operators in their areas: (1) an
estimate of the modeling data and parameters of IBR-DERs in the
aggregate,\202\ (2) an explanation of the limitations of the
availability of data, (3) an explanation of the limitations of the data
provided by IBR-DERs, and (4) the method used for estimation. In
support of above, we further direct NERC to consider commenters'
suggestions to implement a process or mechanism by which distribution
providers would receive modeling data and parameters.\203\
---------------------------------------------------------------------------
\201\ For example, there may be no distribution providers that
meet the NERC Registration Criteria in a given area (e.g., greater
than 75 MW of peak load directly connected to the bulk-electric
system, facilities that are used in protection systems or programs
for the protection of the bulk-electric system, etc.), see NERC
Rules of Procedure App. 5B (Statement of Compliance Registry
Criteria) 6-7, (Jan. 19, 2021), <a href="https://www.nerc.com/FilingsOrders/us/RuleOfProcedureDL/Appendix%205B.pdf">https://www.nerc.com/FilingsOrders/us/RuleOfProcedureDL/Appendix%205B.pdf</a>.
\202\ See supra note 89.
\203\ See infra P 147 (identifying the EPRI DER Settings
Database as one potential technical source for IBR-DER estimation
data).
---------------------------------------------------------------------------
106. Finally, as noted by commenters, we recognize that there may
be instances where IBR-DERs are connected to an entity that does not
meet the criteria for registration with NERC as a distribution
provider. For those areas with IBR-DERs that in the aggregate
materially affect the reliable operation of the Bulk-Power System but
do not have an associated registered distribution provider, we direct
NERC to determine the appropriate registered entity responsible for
providing data of IBR-DERs that in the aggregate have a material impact
on the Bulk-Power System, or, when unable to gather such accurate IBR-
DERs data, to provide instead to the Bulk-Power System planners and
operators in their areas: (1) an estimate of the modeling data and
parameters of IBR-DERs that in the aggregate have a material impact on
the Bulk-Power System, (2) an explanation of the limitations of the
availability of data, (3) an explanation of the limitations of any data
provided by the IBR-DERs that in the aggregate have a material impact
on the Bulk-Power System, and (4) the method used for estimation.
107. We believe that requiring transmission owners and distribution
providers to collect required data for unregistered IBRs, and IBR-DERs
in the aggregate, will result in greater consistency than the piecemeal
approach proposed by Indicated Trade Associations, in which some data
for unregistered IBRs and IBR-DERs in the aggregate would also be
provided by registered generator owners and operators. Further, we
believe that transmission owners and distribution providers are in a
better position to collect and estimate required data for unregistered
IBRs and IBR-DERs in the aggregate that are directly connected to their
respective areas than balancing authorities. We anticipate that the
need for estimated data for unregistered IBRs connected to the Bulk-
Power System, as opposed to actual data, and thus the burden of
collecting such data, will decrease over time due to the model
provision requirements in the pro forma LGIP and pro forma SGIP, as
adopted in Order No. 2023,\204\ and the ongoing NERC activities to
register IBR generator owners and operators.\205\ As transmission
providers modify their interconnection agreements in compliance with
Order No. 2023, we expect that the need to estimate data will decrease
because validated models for smaller sized resources will begin to be
submitted to transmission providers with interconnection requests under
the Commission's pro forma SGIP. NERC's registration of previously
unregistered IBRs should result in more IBRs providing data and
validated models pursuant to applicable Reliability Standards.\206\
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\204\ Order No. 2023, 184 FERC ] 61,054 at P 1659 (revising
Attachment A to Appendix 1 of the pro forma LGIP and Attachment 2 of
the pro forma SGIP to require each interconnection customer
requesting to interconnect a non-synchronous generating facility to
submit to the transmission provider specified modeling information).
\205\ See Order Approving Workplan, 183 FERC ] 61,116 at P 1
(approving NERC's plan to modify its Rules of Procedure related to
registration and to identify and register IBR generator owners and
operators that fall below the thresholds for the bulk-electric
system definition). NERC's Commission approved bulk electric system
definition is a subset of the Bulk-Power System and defines the
scope of the Reliability Standards and the entities subject to NERC
compliance. Revisions to Electric Reliability Org. Definition of
Bulk Elec. Sys. & Rules of Proc., Order No. 773, 141 FERC ] 61,236
(2012), order on reh'g, Order No. 773-A, (May 17, 2013), 143 FERC ]
61,053 (2013), rev'd sub nom. People of the State of N.Y. v. FERC,
783 F.3d 946 (2d Cir. 2015); NERC Glossary at 7-9.
\206\ NERC's August 16, 2023, Compliance Filing sets forth
NERC's proposed registration plan indicating that implementation of
the plan will result in registration of 97.5 percent of Bulk-Power
System connected IBRs of the total IBR nameplate capacity MWs
installed in 2021 of transmission and sub-transmission IBRs.
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108. Regarding CAISO's concern regarding the potential ``compliance
trap'' where planners and operators rely on third-party data \207\ and
IRC's request that the final rule specify the data to be submitted by
all IBRs (i.e., registered IBRs, unregistered IBRs, and IBR-DERs in the
aggregate) and transmission devices using similar technologies, we
direct NERC to determine through its standards development process the
minimum categories or types of data that must be provided to
transmission planners, transmission operators, transmission owners, and
distribution providers necessary to predict the behavior of all IBRs
and to ensure that compliance obligations are clear.\208\ As discussed
in more detail in section IV.C of this final action, we are also
directing NERC to develop new or modified Reliability Standards that
require the use of approved industry IBR models that accurately reflect
the behavior of all IBRs during steady state, short-circuit, and
dynamic conditions. By contrast, we believe that a directive to task
distribution providers as the appropriate registered entity to collect
and share the modeling data and parameters of IBR-DERs in the aggregate
is preferable to deferring to the stakeholder process as suggested by
APS. The distribution provider, as the entity providing and operating
the lines between the transmission and distribution systems,\209\ is
the entity best situated to have access to the data necessary for
accurate estimation and, other than Indicated Trade Associations that
suggested the piecemeal approach already discussed above, no commenter
identified other potential entities as an equally efficient option.
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\207\ CAISO Initial Comments at 38.
\208\ See Order No. 672, 114 FERC ] 61,104 at PP 322, 325
(requiring that Reliability Standards be clear and unambiguous as to
what is required and who is required to comply).
\209\ See NERC Rules of Procedure, App. 5B at 6.
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109. We also decline to either convene a forum to consider the
benefits of applying the new Reliability Standards to distribution
providers with IBR-DERs in their footprints, or direct NERC to submit a
study on the challenges for development and implementation of those new
or modified Reliability Standards as suggested by Indicated Trade
Associations. As identified in the NOPR and expounded upon in this
final action, there is a pressing need to address the gap posed by the
currently effective Reliability Standards. Bulk-Power System planners
and operators need to receive modeling data and parameters regarding
IBR-DERs that in the aggregate are capable of adversely affecting the
reliable operation of the Bulk-Power System. The additional process
proposed by commenters will unnecessarily delay resolution of the
identified gap. Further, regarding various comments suggesting specific
timing for requiring data provision, we believe that determining when
data would be available and required to be provided is better addressed
during the standards development process. We encourage NERC to continue
its efforts to review and evaluate whether reliability gaps continue to
remain and if new or modified functional registration categories or
Reliability Standards are necessary to ensure the reliable operation of
the Bulk-Power System. NERC may choose to revise, or the Commission may
direct further
[[Page 74269]]
revisions to, registration or Reliability Standards to ensure the
provision of adequate modeling data and parameters from unregistered
IBRs and/or IBR-DERs in the aggregate.
C. Data and Model Validation
110. In the NOPR, the Commission preliminarily found that the
currently effective Reliability Standards are inadequate to ensure that
Bulk-Power System planners and operators: (1) have the steady state,
dynamic, and short circuit models of the elements that make up
generation, transmission, and distribution facilities that accurately
reflect the generation resource's behavior in steady state and dynamic
conditions; (2) have dynamic models (i.e., models of equipment that
reflect the equipment's behavior during various grid conditions and
disturbances) that accurately represent the dynamic performance of all
generation resources, including momentary cessation when applicable;
(3) can validate and update resource models by comparing the provided
data and resulting models against actual operational behavior to
achieve and maintain accuracy of their transmission planning and
operations models; and (4) have interconnection-wide models that
represent all generation resources, including: (a) synchronous
generation resource models; (b) load resource models; and (c)
registered and unregistered IBR models, as well as IBR-DERs modeled in
the aggregate. The Commission further stated that Bulk-Power System
planners and operators need accurate planning, operations, and
interconnection-wide models to ensure reliable operation of the
system.\210\
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\210\ NOPR, 181 FERC ] 61,125 at P 82.
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111. Therefore, the Commission proposed to direct NERC to submit to
the Commission for approval one or more new or modified Reliability
Standards that would ensure that all necessary models are validated.
Specifically, the Commission proposed to direct NERC to modify the
Reliability Standards to require: (1) generator owners to provide
validated registered IBR models to the planning coordinators for
interconnection-wide, planning, and operations models; (2) transmission
owners to provide validated unregistered IBR models to the planning
coordinators for interconnection-wide, planning, and operations models;
and (3) distribution providers to provide validated models of IBR-DERs
in the aggregate to the planning coordinators for interconnection-wide,
planning, and operations models. Further, the Commission proposed that
the new or modified Reliability Standards should require models of
individual registered and unregistered IBRs, as well as IBR-DERs in the
aggregate, to represent the dynamic behavior of these IBRs at a
sufficient level of fidelity for Bulk-Power System planners and
operators to perform valid facility interconnection, planning, and
operational studies on a basis comparable to synchronous generation
resources.\211\
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\211\ Id. P 83.
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1. Approved Component Models
112. In the NOPR, the Commission preliminarily found that without
approved generation models that accurately reflect generation resource
behavior in steady state and dynamic conditions, Bulk-Power System
planners and operators are unable to adequately predict IBR behavior
and their subsequent impact on the Bulk-Power System.\212\ The
Commission found that the currently effective Reliability Standards
only refer broadly to models in Reliability Standard MOD-032-1,
Attachment 1, rather than requiring the use of NERC's approved
component models, which would provide more accurate information about
resource behavior. Thus, the Commission proposed to direct NERC to
develop new or modified Reliability Standards that require the use of
approved industry generic library IBR models that accurately reflect
the behavior of IBRs during both steady state and dynamic conditions.
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\212\ Id. P 86 (citing NERC Standardized Powerflow Parameters
and Dynamics Models).
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113. The Commission elaborated that NERC could reference its
approved component model list in the Reliability Standards and require
that only those models be used when developing planning, operations,
and interconnection-wide models. The Commission further stated that the
proposed directives were consistent with the recommendations in the
NERC reports.\213\
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\213\ Id.
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a. Comments
114. AEP, CAISO, ISO-NE, LADWP, and NYSRC generally support the
proposed directive to require the use of approved industry generic
library IBR models \214\ (e.g., NERC's approved model list) instead of
user-defined models.\215\ As an owner of registered IBRs, unregistered
IBRs, and IBR-DERs, AEP confirms that transmission owners and
distribution providers need consistent and accurate data to properly
model IBR behavior.\216\
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\214\ Various commenters reference the type of transmission
power system models used for transmission steady state and dynamic
assessments with a variety of synonymous names. These conventional
transmission power system simulation models may be referred to as
root mean square models or positive-sequence models. These
synonymous model names are sometimes used in combinations and
appended to the terms generic or standardized library models. This
final action uses the most simplified term ``generic library model''
to describe the approved collection of industry transmission power
system models used for steady state, dynamic, and short-circuit
assessments.
\215\ AEP Initial Comments at 3; CAISO Initial Comments at 1;
ISO-NE Reply Comments at 2-3; LADWP Reply Comments at 3 NYSRC
Initial Comments at 4.
\216\ AEP Initial Comments at 3-4.
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115. CAISO supports the use of approved industry generic library
IBR models but suggests that, instead of the NERC approved model list,
the WECC models should be used when developing national standards for
model development and validation.\217\ CAISO explains that the WECC
models have been the subject of numerous research projects undertaken
for the purpose of validating various components and suggests that NERC
and its stakeholders could use this experience when developing
standards for model development and validation.\218\ CAISO notes that
even unregistered IBRs are required to provide dynamic models from the
manufacturer using the latest WECC approved dynamic models.\219\
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\217\ CAISO Initial Comments at 29.
\218\ Id.
\219\ Id. at 26.
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116. LADWP explains that it is challenging for transmission
providers to obtain accurate IBR model information, and often the
supplied modeling data is generic and neither adequate nor high
fidelity.\220\ NYSRC supports establishing validation processes for IBR
projects and plant component models and ensuring that detailed
verifiable models and data are available for planning and operational
studies.\221\ NYSRC explains that such component models may include
individual solar, wind, or storage devices, plant protection systems,
plant controllers, ancillary equipment, and interconnection equipment
(transformers and transmission lines). NYSRC also suggests that the
Commission allow for and consider making clear in any resulting rules
or requirements that provide for mandatory delivery by equipment
manufacturers and project developers of detailed, equipment specific,
verifiable manufacturer's models and data necessary for planning and
operational studies.\222\
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\220\ LADWP Reply Comments at 3.
\221\ NYSRC Initial Comments at 3.
\222\ Id.
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[[Page 74270]]
117. NERC opposes requiring entities to rely solely on standardized
generic library models because such models may not be able to fully
represent IBR behaviors.\223\ Instead, NERC supports establishing an
acceptable model list that identifies which models to use for specific
types of studies.\224\ NERC explains that while user-defined models
have some drawbacks, the Commission should not preclude their use. NERC
also notes that entities may rely on different modeling practices or
types of models and, therefore, recommends an approach that combines:
(1) a positive sequence standard library model; (2) a positive sequence
user-defined model; (3) a detailed EMT model; and (4) a model
benchmarking report that compares all models.\225\ NERC adds that
entities should correctly parameterize all of these models when
performing benchmarking testing to reflect the as-built equipment
installed in the field and include an explanation to the receiving
entity of any limitations with the models.\226\
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\223\ NERC Initial Comments at 15-16.
\224\ Id.
\225\ Id. at 16.
\226\ Id.
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118. Regarding the use of user-defined models, EPRI states that
both generic library models and user-defined models are important to
use--provided that both types of models are appropriately parameterized
and validated. EPRI further explains that user-defined models may be
more accurate in certain kinds of studies that require unique controls
or protection strategies, which generic models may not have. EPRI
therefore suggests that the Commission consider requiring both
validated user-defined models and validated generic library
models.\227\
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\227\ EPRI Initial Comments at 17.
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119. While ACP/SEIA generally support the Commission's proposed
directive to require NERC to develop Reliability Standards that address
modeling of IBRs, they recommend giving the transmission service
provider the discretion to require user-defined models, generic library
models (with site-specific parameterization), or both.\228\
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\228\ ACP/SEIA Initial Comments at 12-13.
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120. ISO-NE explains that it only accepts a user-defined model if
there is no generic library model that could be used.\229\ ISO-NE
explains that it has found that user-defined models are not uniform and
may conflict with other user-defined models. Accordingly, ISO-NE
supports the Commission's proposal to require the use of approved
industry generic library models or, if the Commission declines to
proceed with the proposed directive, asks that the final rule either
not require the use of user-defined models or allow entities to
preclude their use.\230\
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\229\ ISO-NE Reply Comments at 3.
\230\ Id.
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121. Although the Commission did not propose to include directives
addressing EMT models, multiple commenters suggest that the Commission
include requirements for EMT models in the final rule.\231\
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\231\ See, e.g., NERC Initial Comments at 13; ACP/SEIA Initial
Comments at 12; SPP Initial Comments at 3; EPRI Initial Comments at
18; Indicated Trade Associations Initial Comments at 7 (although
also noting that EMT modeling can be burdensome to industry); ISO-NE
Initial Comments at 2-3.
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b. Commission Determination
122. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR
proposal and direct NERC to develop new or modified Reliability
Standards that require the use of approved industry generic library IBR
models that accurately reflect the behavior of IBRs during steady
state, short-circuit, and dynamic conditions when developing planning,
operations, and interconnection-wide models. For example, the new or
modified Reliability Standards could reference the NERC approved
component model list, which defines the models that may be used, and
those models that may not be used, for specific types of studies.\232\
This approved component model list includes WECC's IBR models. Without
requiring the use of approved industry generic library models, Bulk-
Power System planners and operators may not be able to create system
models that adequately predict IBR behaviors and subsequent impacts on
the Bulk-Power System.\233\
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\232\ See NERC Standardized Powerflow Parameters and Dynamics
Models.
\233\ NOPR, 181 FERC ] 61,125 at P 36.
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123. We decline to modify the NOPR proposal to allow NERC the
discretion to include alternatives to approved industry generic library
models in any new or modified Reliability Standards, and we similarly
decline to modify the NOPR proposal to allow transmission providers the
discretion to diverge from the approved nation-wide component model
list. While Order No. 2023 allows interconnection customers to submit
novel user-defined models with their interconnection requests,\234\ the
risks associated with the use of user-defined models in the
interconnection context are substantially different than in the Bulk-
Power System operations and planning context. Specifically,
interconnection studies require the transmission provider to study
impacts from integrating a new resource on their system; these internal
models are not typically shared or combined with models from
neighboring systems. In contrast, in the transmission planning and
operations context, planning coordinators, transmission planners,
transmission operators, and balancing authorities combine models on
both a regional and interconnection-wide basis to assess and mitigate
impacts from a number of system conditions and contingencies on their
portion of the Bulk-Power System. In the event of non-convergence or
other problems with the model, a user-defined model, if not
appropriately parameterized and not submitted with open-source code or
dynamic link library and code files, may not allow internal model
components to be viewed or modified, which would impede the ability of
planning coordinators, transmission planners, transmission operators,
and balancing authorities to remediate any issues. Accordingly, while
user-defined models may be acceptable to an individual transmission
provider when building its own models and studying its own system,
which we are not prohibiting here, the use of a standard set of
approved industry generic library models is essential to creating Bulk-
Power System planning and operations system models (i.e., combining
models between neighboring entities and for interconnection-wide
models) so that Bulk-Power System planners and operators can adequately
predict behaviors and subsequent impacts to the reliable operation of
the Bulk-Power System.
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\234\ See Order No. 2023, 184 FERC ] 61,054 at P 1660.
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124. We direct NERC to determine through its standards development
process which nation-wide approved component models are needed to build
IBR plant models for steady state, short-circuit, and dynamics studies.
We acknowledge NERC's comment that user-defined models may be helpful
for specific local reliability studies; however, the user-defined model
cannot be used in place of nation-wide approved component models for
regional analysis or interconnection-wide analysis because the user-
defined model may cause non-convergence and other issues.\235\ However,
NERC may
[[Page 74271]]
allow the submission of user-defined models alongside the approved
industry generic IBR model. Various entities do not accept user-defined
models or only accept them for limited instances along with the open-
source code which then allows internal model components to be viewed
and modified. For example, PJM does not accept user-defined models and
requires generic models for model verification in accordance with
currently effective Reliability Standards MOD-026-1 and MOD-027-1.\236\
NYISO accepts a user-defined model in limited instances but requires
either the open-source code (allowing anyone to access the internal
model) or dynamic link library data and code files (compiled code that
must be decompiled to view the internal model) that must be supplied
for existing power flow software and in perpetuity.\237\
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\235\ See NERC, Libraries of Standardized Powerflow Parameters
and Standardized Dynamics Models, Ver. 1 at 1 (Oct. 15, 2015),
<a href="https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf">https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf</a> (explaining
that since Bulk-Power System planning and operations system models
are constructed using thousands of individual component models,
there can be problems when using models that are proprietary or
confidential, because it ``impedes the free flow of information
necessary for interconnection[hyphen]wide power system analysis and
model validation.'' Further, the document recommends ``an
industry[hyphen]wide forum for discussing the validity of these
various model structures'' and that ``industry should agree upon
standardized component model structures and associated parameters
for particular types of equipment.'').
\236\ See PJM, Guidance for NERC MOD-026-027 Generation Owner
Preparation & Submittal, 5 (Aug. 28, 2022), <a href="https://www.pjm.com/-/media/library/whitepapers/compliance/20220828-guidance-for-go-to-prepare-nerc-mod-026-027-and-submittal.ashx">https://www.pjm.com/-/media/library/whitepapers/compliance/20220828-guidance-for-go-to-prepare-nerc-mod-026-027-and-submittal.ashx</a> (explaining that ``user-
defined models are not acceptable. PJM requires submittal of generic
models with appropriate due diligence made to closely match unit
performance'').
\237\ See NYISO, Reliability Analysis Data Manual, 22 (Dec.
2022), <a href="https://www.nyiso.com/documents/20142/2924811/M-24-RAD-Att%20B-v2022-12-07-Final.pdf/d91ccb08-d34b-1890-c85a-baa21712d9d4">https://www.nyiso.com/documents/20142/2924811/M-24-RAD-Att%20B-v2022-12-07-Final.pdf/d91ccb08-d34b-1890-c85a-baa21712d9d4</a>
(explaining that if a user-defined model is provided then a
technical justification must accompany the model along with the
open-source code of the model; if the open-source code cannot be
provided then all dynamic link library data and code files must be
supplied for existing power flow software and all future versions of
the power flow software).
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125. Accordingly, we direct NERC to develop new or modified
Reliability Standards that require the sole use of nation-wide approved
component generic library models for system models to facilitate the
exchange of neighboring entities' respective planning and operation
models and to build interconnection-wide models. One example of a way
NERC could meet this directive would be to require an equivalent
generic library model along with all submissions of user-defined models
so that the generic library model can be used when combining
neighboring transmission system models and in interconnection-wide
models.
126. With respect to NERC's recommendation for model benchmarking,
we direct NERC to determine through its standards development process
whether the development of benchmark cases to test model performance
and a subsequent report comparing model performance are needed and at
what periodicity.
127. Many commenters request that the Commission consider requiring
the inclusion of EMT models in the new or modified Reliability
Standards. In Order No. 2023, the Commission required interconnection
customers to submit EMT models with their interconnection requests only
if the transmission provider performs an EMT study as part of its
interconnectio
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