[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 [www.gpo.gov]
[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

[[Page 74250]]


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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...
 


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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), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf (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), https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf.
    \11\ NERC, Inverter-Based Resource Strategy: Ensuring 
Reliability of the Bulk Power System with Increased Levels of BPS-
Connected IBRs, 1 (June 2022), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf (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), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf (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

[[Page 74252]]

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), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf (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), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf (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), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf (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), https://www.nrel.gov/docs/fy20osti/73856.pdf.
    \26\ NERC and WECC, San Fernando Disturbance, 2 (Nov. 2020), 
https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf (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), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf (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 
https://www.nerc.com/pa/Stand/Pages/USRelStand.aspx.
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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), https://www.nerc.com/pa/Documents/2023_NERC_Guide_Inverter-Based-Resources.pdf (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), https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf (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), https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf (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.'').
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \34\ See NERC, Resource Loss Protection Criteria Assessment, 
(Feb. 2018), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf.
    \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.
---------------------------------------------------------------------------

    \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\
---------------------------------------------------------------------------

    \38\ NOPR, 181 FERC ] 61,125 at P 1.
    \39\ Id. P 2 (citing 2020 LTRA Report).
    \40\ Id.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \41\ Id. P 6.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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), 
https://www.nerc.com/AboutNERC/RulesOfProcedure/NERC%20ROP%20effective%2020220825_with%20appendicies.pdf.
    \43\ NOPR, 181 FERC ] 61,125 at P 5.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \45\ Id.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    \50\ See NOPR, 181 FERC ] 61,125 at PP 24-26.
    \51\ Id. PP 26-27.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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), 
https://www.iso-ne.com/static-assets/documents/2023/01/20230124-gen-data-submittal-requirements-planning.pdf.
---------------------------------------------------------------------------

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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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), https://ftp.puc.texas.gov/public/puct-info/agency/resources/reports/leg/PUC_Load_Shed_Protocols_Study.pdf. See also 
NERC Newsroom Announcement Odessa Disturbance Illustrates Need for 
Immediate Industry Action on Inverter-Based Resources (Dec. 8, 
2022), https://www.nerc.com/news/Headlines%20DL/OdessaDisturbance_08DEC22.pdf (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), 
https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2022_Odessa_Disturbance_Report%20(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\
---------------------------------------------------------------------------

    \58\ NERC, Industry Recommendation: Inverter-Based Resource 
Performance Issues (Mar. 2023), 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 (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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \62\ NERC and WECC, 2023 Southwest Utah Disturbance (Aug. 2023), 
https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2023_Southwest_UT_Disturbance_Report.pdf (Southwest Utah 
Disturbance Report).
    \63\ Id. at iv.
    \64\ Id.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \65\ Multiple Solar PV Disturbances in CAISO: Disturbances 
between June and August 2021 Joint NERC and WECC Staff Report, 17-
18, (Apr. 2022), https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf.
    \66\ San Fernando Disturbance: Southern California Event: July 
7, 2020 Joint NERC and WECC Staff Report, 12 (Nov. 2020), https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \67\ NERC, Reliability Guideline: Parameterization of the DER_A 
Model for Aggregate DER (Feb. 2023), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_ModelingMerge_Responses_clean.pdf (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, https://www.esig.energy/wiki-main-page/parameterization-d1/.
    \68\ NERC, Reliability Guideline: Electromagnetic Transient 
Modeling for BPS-Connected Inverter-Based Resources--Recommended 
Model Requirements and Verification Practices (Mar. 2023), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline-EMT_Modeling_and_Simulations.pdf (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\
---------------------------------------------------------------------------

    \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, 
https://www.nerc.com/pa/Stand/Pages/Standards-Under-Development.aspx.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \70\ March 2023 Alert at 6-7.
    \71\ Id. at 6.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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).
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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), https://standards.ieee.org/ieee/2800/10453/ (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), https://standards.ieee.org/ieee/1547/5915/ (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, https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673.
    \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, 
https://standards.ieee.org/ieee/2800/10453/ (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, https://sagroups.ieee.org/scc21/standards/1547rev/; 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), https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf (Loss of Solar Resources Alert II) (describing examples 
of planning and operational IBR data); NERC and Texas RE, Odessa 
Disturbance, 20-21 (Sept. 2021), https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf (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), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf (Western Interconnection Base Case 
IBR Review); NERC, Reliability Guideline: DER Data Collection for 
Modeling in Transmission Planning Studies (Sept. 2020), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf (IBR-DER 
Data Collection Guideline).
    \82\ NOPR, 181 FERC ] 61,125 at P 28.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \83\ See NERC, Technical Report, BPS-Connected Inverter-Based 
Resource Modeling and Studies, 35 (May 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF&_IBR_Modeling_and_Studies_Report.pdf (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).
---------------------------------------------------------------------------

    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), https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf (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'').
---------------------------------------------------------------------------

    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), https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf (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), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf (Odessa Disturbance White Paper)).
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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.).
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    \91\ See Reliability Standard MOD-033-2 (Steady-State and 
Dynamic System Model Validation).
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \94\ NERC, Libraries of Standardized Powerflow Parameters and 
Standardized Dynamics Models version 1, 1 (Oct. 2015), https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf (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), https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf (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), https://www.epri.com/research/products/000000003002006525 (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).
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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), https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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\
---------------------------------------------------------------------------

    \113\ See NOPR, 181 FERC ] 61,125 at P 4.
---------------------------------------------------------------------------

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), https://www.eia.gov/outlooks/aeo/narrative/index.php#TheElectricityMixinth (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 https://www.eia.gov/energyexplained/renewable-sources/. 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.
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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\
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    \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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    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), https://nyiso.force.com/MemberCommunity/s/article/What-to-expect-when-submitting-a-CEII-Request-form; CAISO, 
Application access, http://www.caiso.com/participate/Pages/ApplicationAccess/Default.aspx (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.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

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\
---------------------------------------------------------------------------

    \166\ See NERC, NERC Inverter-Based Resource Performance Task 
Force (IRPTF)Review of NERC Reliability Standards White Paper, at 1 
(Mar. 2020), https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf 
(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.
---------------------------------------------------------------------------

    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'').
---------------------------------------------------------------------------

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), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf (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\
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    \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), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf (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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \180\ IRC Initial Comments at 2.
    \181\ Id. at 3.
---------------------------------------------------------------------------

    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), https://www.nerc.com/FilingsOrders/us/RuleOfProcedureDL/Appendix%205B.pdf.
    \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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \210\ NOPR, 181 FERC ] 61,125 at P 82.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \211\ Id. P 83.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    \212\ Id. P 86 (citing NERC Standardized Powerflow Parameters 
and Dynamics Models).
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \213\ Id.
---------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \217\ CAISO Initial Comments at 29.
    \218\ Id.
    \219\ Id. at 26.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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\
---------------------------------------------------------------------------

    \223\ NERC Initial Comments at 15-16.
    \224\ Id.
    \225\ Id. at 16.
    \226\ Id.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \227\ EPRI Initial Comments at 17.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \228\ ACP/SEIA Initial Comments at 12-13.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \229\ ISO-NE Reply Comments at 3.
    \230\ Id.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

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\
---------------------------------------------------------------------------

    \232\ See NERC Standardized Powerflow Parameters and Dynamics 
Models.
    \233\ NOPR, 181 FERC ] 61,125 at P 36.
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \234\ See Order No. 2023, 184 FERC ] 61,054 at P 1660.
---------------------------------------------------------------------------

    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\
---------------------------------------------------------------------------

    \235\ See NERC, Libraries of Standardized Powerflow Parameters 
and Standardized Dynamics Models, Ver. 1 at 1 (Oct. 15, 2015), 
https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf (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), https://www.pjm.com/-/media/library/whitepapers/compliance/20220828-guidance-for-go-to-prepare-nerc-mod-026-027-and-submittal.ashx (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), https://www.nyiso.com/documents/20142/2924811/M-24-RAD-Att%20B-v2022-12-07-Final.pdf/d91ccb08-d34b-1890-c85a-baa21712d9d4 
(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).
---------------------------------------------------------------------------

    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 
interconnection study process.\238\ We decline here, however, to direct 
NERC to require EMT models at this time because EMT models are 
typically used to examine the electromagnetic transient behavior of 
individual generation resources and to study plant-to-plant 
interactions. EMT models are not used to build interconnection-wide 
models or perform respective studies and, as such, requiring their 
inclusion would not address the reliability gaps identified in section 
III above, which are the subject of the directives in this final 
action. However, we note that NERC has existing and ongoing Reliability 
Standards projects that include EMT studies,\239\ and we encourage NERC 
and stakeholders to continue working in this area.
---------------------------------------------------------------------------

    \238\ See Order No. 2023, 184 FERC ] 61,054 at P 1659.
    \239\ See NERC Initial Comments at 14 (describing multiple EMT 
modeling projects including a taskforce, Reliability Standards 
Project 2022-04 (EMT Modeling), and a reliability guideline).
---------------------------------------------------------------------------

2. Verification of IBR Plant Dynamic Model Performance
    128. In the NOPR, the Commission proposed to direct NERC to require 
the generator owners of registered IBRs and the transmission owners 
that have unregistered IBRs on their systems to provide dynamic models 
that accurately represent the dynamic performance of facilities of 
registered IBRs and facilities of unregistered IBRs, including 
momentary cessation and/or tripping, and all ride through behavior to 
the planning coordinators, transmission planners, reliability 
coordinators, transmission operators, and balancing authorities. The 
Commission further proposed to direct NERC to require distribution 
providers that have IBR-DERs on their systems to ensure that the 
aggregated dynamic models (i.e., plant models that describe the 
behaviors of all IBRs installed and controlled at a single electrical 
location) provided to the planning coordinators, transmission planners, 
reliability coordinators, transmission operators, and balancing 
authorities accurately represent the dynamic performance of IBR-DER 
facilities in the aggregate, including momentary cessation and/or 
tripping, and all ride through behavior (e.g., IBR-DERs in the 
aggregate modeled by interconnection requirements performance to 
represent different steady-state and dynamic behavior).\240\
---------------------------------------------------------------------------

    \240\ NOPR, 181 FERC ] 61,125 at P 84.
---------------------------------------------------------------------------

    129. In the NOPR, the Commission noted that the currently effective 
Reliability Standards do not require generator owners to provide 
verified models and data for IBR-specific controls (e.g., power plant 
central controller functions and protection system settings), do not 
require transmission owners to provide verified dynamic models for 
unregistered IBRs, and do not require distribution providers to provide 
verified dynamic models for IBR-DERs in the aggregate. The Commission 
therefore proposed to direct NERC to develop new or modified 
Reliability Standards that account for the technological differences 
between IBRs and synchronous generation resources.
a. Comments
    130. Commenters generally support the proposed NOPR directive that 
the new or modified Reliability Standards require that entities verify 
all IBR models.\241\ For example, NERC confirms that the currently 
effective Reliability Standards, such as MOD-026-1 and MOD-027-1, which 
pertain to model verification, could be enhanced by requiring entities 
to verify that the models are of sufficient accuracy and to make 
corrections in a timely manner.\242\ Additionally, NERC states that it 
has recommended that the Project 2020-06 (Verifications of Models and 
Data for Generators) standard drafting team employ a more comprehensive 
model validation process. This includes equipment manufacturer 
engagement (e.g., by attesting to model quality), submitting as-built 
protection and controls, hardware-in-the-loop testing, testing/
operations data, and considering future IEEE P2800.2 model validation 
and verification procedures.\243\
---------------------------------------------------------------------------

    \241\ Although the NOPR and this final action use 
``verification'' to mean the model is properly parameterized and 
validated, and ``validation'' to mean the confirmation that models 
reflect real world operational behaviors, commenters use the terms 
verification and validation interchangeably in their responses.
    \242\ NERC Initial Comments at 12 (stating that NERC Project 
2020-06 (Verifications of Models and Data for Generators) is already 
developing revisions to enhance requirements for model 
verification).
    \243\ Id. at 17.

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[[Page 74272]]

    131. EPRI supports dynamic model verification and generally 
recommends that the new or modified Reliability Standards use the 
precise language and definitions as published in the industry standards 
and aligning requirements with leading international practice and grid 
codes.\244\ EPRI points to the IEEE P2800.2 test and verification 
procedures currently under development as an example of how NERC may 
align with industry requirements for IBR plant model verification. 
Specifically, EPRI explains that the IEEE P2800.2 working group is 
developing a recommended practice for test and verification procedures 
that will include procedures, criteria, and definitions.\245\
---------------------------------------------------------------------------

    \244\ EPRI Initial Comments at 8.
    \245\ Id. at 19-20 (referring to IEEE, Test and Verification of 
BPS-connected Inverter-Based Resources, P2800-2, https://sagroups.ieee.org/2800-2/).
---------------------------------------------------------------------------

    132. To ensure the appropriate dynamic model data is provided, IRC 
requests that the final rule specify that the data to be submitted by 
transmission devices using similar technologies include data to study 
IBR dynamic behavior (e.g., data for EMT studies).\246\ Further, IRC 
suggests including the equipment testing and field tests as a part of 
model validation to show that the models accurately represent the 
equipment as installed in the field. IRC also recommends including 
requirements to model and study IBR installations to capture certain 
adverse control interactions that would be unseen by IBR owner modeling 
efforts but would still create reliability issues seen by the 
reliability coordinators, transmission planners, or planning 
authorities.\247\
---------------------------------------------------------------------------

    \246\ IRC Initial Comments at 3.
    \247\ Id. at 4.
---------------------------------------------------------------------------

    133. CAISO supports the proposed directive to require NERC to 
ensure that the new or modified Reliability Standards account for 
verification of IBR plant dynamic model performance. CAISO emphasizes 
that the new or modified Reliability Standards should include 
requirements that enable the registered entities responsible for 
planning and operating the Bulk-Power System to validate data of 
registered IBRs and unregistered IBRs and data of IBR-DERs in the 
aggregate, by comparing the provided data and resulting models with 
actual performance and behavior.\248\
---------------------------------------------------------------------------

    \248\ CAISO Initial Comments at 30.
---------------------------------------------------------------------------

    134. NERC, AEU, EPRI, and ACP/SEIA express concerns about the 
availability of verified IBR dynamic models. EPRI explains that 
transmission providers may need to reevaluate or restudy 
interconnection requests because site-specific verified plant models 
may not be available at the time of the facility interconnection 
studies, and the restudy would therefore create delays to the generator 
interconnection process.\249\ Further, ACP/SEIA and LADWP raise 
concerns with the timelines for when such model data should be 
required. For example, ACP/SEIA note that as plant settings change, it 
may be difficult to provide fully validated models during the 
interconnection process and, therefore, EMT models should only be 
required once equipment details and settings are final, which occurs at 
the end of the interconnection process.\250\ LADWP similarly notes the 
challenge of obtaining accurate model information if the 
interconnection customer has not actually purchased its equipment for 
use in a project.\251\ NERC and AEU recommend that the Commission 
clarify in the final rule that a registered IBR would not be subject to 
the dynamic model requirements until the facility has completed the 
facility interconnection process and achieved commercial 
operation.\252\ AEU supports focusing the requirements proposed in the 
NOPR on the fidelity of models and data provided at the completion of 
the facility interconnection process and on the model validation steps 
that can be taken following a plant commissioning.\253\ ACP/SEIA 
recommend that the Commission direct NERC to develop a process for 
registered generators, including IBRs, to provide validated models to 
transmission planners in a reasonable timeframe following completion of 
the facility interconnection process.\254\
---------------------------------------------------------------------------

    \249\ EPRI Initial Comments at 22.
    \250\ ACP/SEIA Initial Comments at 12.
    \251\ LADWP Reply Comments at 3.
    \252\ NERC Initial Comments at 12; AEU Initial Comments at 6.
    \253\ AEU Initial Comments at 6.
    \254\ ACP/SEIA Initial Comments at 13.
---------------------------------------------------------------------------

    135. ISO-NE requests that the Commission make clear that generator 
owners, transmission owners, and distribution providers--and not 
transmission planners or transmission operators--should provide 
validated models to planning coordinators. ISO-NE requests that the 
Commission make clear that generator owners, transmission owners, and 
distribution providers should provide validated models to planning 
coordinators, and not transmission planners or transmission operators. 
ISO-NE and IRC also request that the Commission state in the final rule 
that model validation should include equipment testing and field tests 
that show the models accurately represent the equipment and control 
settings as installed in the field.\255\ Finally, ISO-NE asks the 
Commission to direct NERC to add distribution providers as an 
applicable entity for Reliability Standard MOD-032-1 so planning 
coordinators and transmission planners are able to obtain IBR-DER 
information.\256\
---------------------------------------------------------------------------

    \255\ ISO-NE Initial Comments at 3; IRC Initial Comments at 4.
    \256\ ISO-NE Initial Comments at 4.
---------------------------------------------------------------------------

    136. EPRI also expresses concerns about model parameterization and 
recommends that the Reliability Standards require generator owners, 
transmission owners, and distribution providers to share verified and 
appropriately parameterized modeling.\257\
---------------------------------------------------------------------------

    \257\ EPRI Initial Comments at 12-13.
---------------------------------------------------------------------------

    137. NERC, APS, and Indicated Trade Associations caution that it 
may be difficult to verify models for unregistered IBRs and IBR-DERs in 
the aggregate because transmission owners and distribution providers do 
not own the assets they would need to address and, therefore, 
flexibility may be warranted.\258\ NERC suggests that, in lieu of 
mandating that an entity provide a validated model, the Commission 
could require the transmission owner, distribution provider, 
transmission planner, or planning coordinator to work collaboratively 
with state regulators to identify, implement, and perform an effective 
model validation approach for IBR-DERs in the aggregate.\259\ 
Additionally, the planning coordinator could, as part of system 
validation in Reliability Standard MOD-033-2, work with the 
distribution provider, transmission planner, reliability coordinator, 
transmission operator, and balancing authority to capture disturbance 
information such that the representation of IBR-DERs in the aggregate 
in their models can be validated against system performance.\260\
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    \258\ NERC Initial Comments at 32; APS Initial Comments at 5; 
Indicated Trade Association Reply Comments at 2.
    \259\ NERC Initial Comments at 32.
    \260\ Id.
---------------------------------------------------------------------------

    138. Indicated Trade Associations and APS express concerns about 
distribution providers verifying models for IBR-DERs in the aggregate. 
APS states that the current method does not account for distributed 
energy resource parameters for running field tests to verify the 
accuracy of the model and that field test methodologies do not exist to 
verify the aggregate IBR-DERs at the feeder level.\261\ APS asserts 
that, even if the distribution providers provide an

[[Page 74273]]

aggregated approximation based on a generic model without engaging 
manufacturers and solar developers, the root cause will not be 
addressed because distribution providers do not have sufficient 
information to create models.\262\ Noting that distribution providers 
do not have the ability to monitor whether the individual IBR-DERs have 
been altered, APS indicates that it would be difficult for distribution 
providers to know the precise mix of IBR-DERs when developing aggregate 
IBR-DER modeling.
---------------------------------------------------------------------------

    \261\ APS Initial Comments at 5.
    \262\ Id.
---------------------------------------------------------------------------

    139. SPP expresses concerns with the types of models that are 
proposed to be verified (i.e., regular power flow models and dynamic 
models). SPP requests that the Commission require EMT model 
verification because only some IBR behaviors can be recognized and 
evaluated in an EMT study. Specifically, SPP requests that the 
Commission direct NERC to identify all three model types (power flow, 
dynamic, and EMT) in new Reliability Standards as the models that 
should be verified.\263\
---------------------------------------------------------------------------

    \263\ SPP Initial Comments at 3.
---------------------------------------------------------------------------

b. Commission Determination
    140. 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 generator owners of registered IBRs, 
transmission owners that have unregistered IBRs on their system, and 
distribution providers that have IBR-DERs on their system to provide 
models that represent the dynamic behavior of these IBRs at a 
sufficient level of fidelity to provide to Bulk-Power System planners 
and operators to perform valid interconnection-wide, planning, and 
operational studies on a basis comparable to synchronous generation 
resources.
    141. We also direct NERC to require the generator owners of 
registered IBRs and the transmission owners that have unregistered IBRs 
on their system to provide to the Bulk-Power System planners and 
operators (e.g., planning coordinators, transmission planners, 
reliability coordinators, transmission operators, and balancing 
authorities) dynamic models that accurately represent the dynamic 
performance of registered and unregistered IBRs, including momentary 
cessation and/or tripping, and all ride through behavior. Recognizing 
that there may be instances in which transmission owners are unable to 
gather accurate unregistered IBR modeling data and parameters to create 
and maintain accurate unregistered IBR dynamic 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, dynamic 
models of unregistered IBRs using estimated data in accordance with 
this final action's section IV.B.3 data sharing directives. Further, we 
direct NERC to require distribution providers to provide to the 
planning coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities aggregated dynamic 
models that adequately represent the dynamic performance of IBR-DERs on 
their systems that in the aggregate have a material impact on the Bulk-
Power System, including momentary cessation and/or tripping, and all 
ride through behavior (e.g., IBR-DERs in the aggregate modeled by 
interconnection requirements performance to represent different steady-
state and dynamic behavior). Recognizing that there may be instances in 
which distribution providers are unable to gather data that accurately 
represents IBR-DERs in the aggregate, we modify the NOPR proposal and 
direct NERC to include in the proposed new or modified Reliability 
Standards a requirement that the distribution provider, if unable to 
gather data of IBR-DERs that in the aggregate have a material impact on 
the Bulk-Power System, provide to the Bulk-Power System planners and 
operators (i.e., the data recipients) a dynamic model using estimated 
data for IBR-DERs that in the aggregate have a material impact on the 
Bulk-Power System, in accordance with this final action's section 
IV.B.3 data sharing directives. Furthermore, we acknowledge that there 
may be areas with IBR-DERs in the aggregate that materially impact the 
reliable operation of the Bulk-Power System but do not have an 
associated registered distribution provider. Therefore, we modify the 
NOPR proposal and direct NERC to determine the appropriate registered 
entity responsible for providing adequate data and parameters of IBR-
DERs that in the aggregate have a material impact on the Bulk-Power 
System, and to identify the registered entities for coordinating, 
verifying, and keeping up to date the respective dynamic models. 
Finally, NERC must ensure that the proposed new or modified Reliability 
Standards account for the dynamic performance of IBR-DERs that in the 
aggregate have a material impact on the Bulk-Power System.
    142. Regarding ISO-NE's request, we decline to direct NERC to 
require generator owners, transmission owners, and distribution 
providers to provide validated models to planning coordinators, and not 
transmission planners or transmission operators; we believe all Bulk-
Power System planners and operators (i.e., planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities) need validated models. 
Additionally, we agree with ISO-NE's request to direct NERC to add 
distribution providers as an applicable entity for Reliability Standard 
MOD-032-1 so planning coordinators and transmission planners are able 
to obtain IBR-DER information. We believe this is addressed through 
directives in section IV.B.3. that require NERC to submit new or 
modified Reliability Standards to address this issue. We decline to 
explicitly direct NERC to make the modification to Reliability Standard 
MOD-032-1 because NERC may address this concern in an equally efficient 
and effective manner.
    143. Regarding EPRI's recommendation to require appropriately 
parameterized plant models, we agree that the model verification 
process of an IBR model should include steps to ensure that responsible 
entities provide both verified and appropriately parameterized 
models.\264\ Additionally, we agree with IRC's recommendation that the 
plant model verification process should include requirements for 
equipment to be represented as installed in the field. While we decline 
to include this level of detail in the directive to NERC, we 
nonetheless direct NERC to establish a standard uniform model 
verification process. A uniform model verification process will ensure 
that all entities use the same set of minimum requirements to verify 
that all generation resource (i.e., synchronous and non-synchronous) 
models are complete and that the models accurately represent the 
dynamic behavior of all generation resources at a sufficient level of 
fidelity for Bulk-Power System planners and operators to perform valid 
interconnection-wide, planning, and operational studies. Therefore, we 
direct NERC to define the model verification

[[Page 74274]]

process and to require consistency among the model verification 
processes for existing Reliability Standards (e.g., FAC-002, MOD-026, 
and MOD-027) and any new or modified Reliability Standards.\265\
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    \264\ We believe that the model verification process should 
ensure that the IBR model inputs are appropriately parameterized as 
well as confirming that the in-field equipment behavior is 
consistent with model behavior.
    \265\ We note NERC's statement that through Project 2020-06 
(Verifications of Models and Data for Generators), it is already 
working to develop revisions to enhance requirements for model 
verification under MOD-026 and MOD-027. See NERC Initial Comments at 
12, 17.
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    144. As the Commission indicated in the NOPR, the DER_A model 
represents an appropriate basis on which to develop new or revised 
modeling standards for IBR-DERs.\266\ In the NOPR, the Commission 
referenced the DER_A model as a potential solution to address the 
requirements for distribution providers to share modeling data and 
parameters regarding IBR-DERs in the aggregate and cited the use of the 
DER_A model as a way to implement the requirement to develop new or 
modified Reliability Standards.\267\ The DER_A model represents IBR-
DERs in the aggregate and NERC recommends it as the approved steady 
state and dynamic model.\268\ WECC and EPRI have verified and updated 
the DER_A model \269\ to model IBR-DERs in the aggregate and have used 
it to study the potential impacts of IBR-DERs in the aggregate on the 
Bulk-Power System. Since 2016, NERC has issued six Reliability 
Guidelines on the DER_A model.\270\ For example, NERC's 2020 IBR-DER 
Data Collection Guideline explains how the distribution provider may be 
able to use publicly available data to provide estimated aggregate IBR-
DER modeling data and parameters to the Bulk-Power System planners and 
operators that they may in turn use as inputs into the DER_A 
model.\271\
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    \266\ NOPR, 181 FERC ] 61,125 at P 79 n.157, P 80 n.159.
    \267\ Id.
    \268\ See NERC Standardized Powerflow Parameters and Dynamics 
Models.
    \269\ See EPRI, The New Aggregated Distributed Energy Resources 
(der_a) Model for Transmission Planning Studies: 2019 Update (Mar. 
2019) https://www.epri.com/research/products/000000003002015320 
(describing the specifications of the model and presenting the 
results of the benchmark tests conducted by EPRI during the approval 
process of the model through WECC's Modeling and Validation Working 
Group).
    \270\ The six NERC DER_A model guidelines are: (1) NERC, 
Reliability Guideline: Modeling Distributed Energy Resources in 
Dynamic Load Models (Dec. 2016), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_-_Modeling_DER_in_Dynamic_Load_Models_-_FINAL.pdf (retired); (2) 
NERC, Reliability Guideline: Distributed Energy Resources Modeling 
(Sept. 2017), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_-_DER_Modeling_Parameters_-_2017-08-18_-_FINAL.pdf (retired); (3) 2019 DER_A Model Guideline; (4) IBR-DER 
Data Collection Guideline; (5) NERC, Reliability Guideline: Model 
Verification of Aggregate DER Models used in Planning Studies (Mar. 
2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline%20_DER_Model_Verification_of_Aggregate_DER_Models_used_in_Planning_Studies.pdf (Aggregate DER Model Verification 
Guideline); and (6) 2023 DER_A Model Guideline.
    \271\ IBR-DER Data Collection Guideline, 1-2 n.37 (recommending 
that distribution providers are the best suited to provide DER 
information to transmission planners and planning coordinators for 
modeling purposes).
---------------------------------------------------------------------------

    145. NERC has provided transmission planners and planning 
coordinators with guidance on how to perform varying extents of DER_A 
model verification using differing amounts of estimated and measured 
data to ensure the aggregate impacts from the DER_A model reflects 
actual Bulk-Power System disturbance behaviors.\272\ Further, NERC's 
2023 DER_A Model Guideline provides transmission planners and planning 
coordinators with a set of recommendations for developing the 
parameters for the DER_A dynamic model, and the recommendations can 
also be extrapolated to transmission operators, reliability 
coordinators, and other entities performing stability simulations of 
the Bulk-Power System where an aggregate representation of DERs (i.e., 
both synchronous resources and IBR-DERs) is required. This guideline 
also provides examples on how the DER_A model parameters can be 
modified to account for a mixture of legacy and newer IBR-DERs.\273\
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    \272\ See generally Aggregate DER Model Verification Guideline.
    \273\ See generally 2023 DER_A Model Guideline.
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    146. Accordingly, we direct NERC to develop new or modified 
Reliability Standards that require the use of the DER_A model or 
successor models to represent the behaviors of IBR-DERs that in the 
aggregate have a material impact on the Bulk-Power System at a 
sufficient level of fidelity for Bulk-Power System planners and 
operators to create valid planning and operations and interconnection-
wide models and to be able to perform respective system studies. For 
example, the new or modified Reliability Standards could require models 
of IBR-DERs (i.e., DER_A model) to adequately reflect the steady-state 
and dynamic aggregate resource performance in both a transmission area 
and across the interconnection. Additionally, estimated modeling data 
and parameters of IBR-DERs that in the aggregate (i.e., DER_A model) 
have a material impact on the Bulk-Power System could be used where 
measured and collected data is not available. We believe requiring the 
DER_A model will address NERC's request for entities to work 
collaboratively with the state regulators to identify, implement, and 
perform an effective model validation approach for IBR-DERs in the 
aggregate as opposed to requiring validated models of IBR-DER in the 
aggregate that can have a material impact on the reliable operation of 
the Bulk-Power System.
    147. Further, to address commenters' concerns about situations when 
distribution providers are unable to gather and provide data of IBR-
DERs in the aggregate, we note the existence and suggest, but decline 
to direct, the use of the EPRI DER Settings Database.\274\ The EPRI DER 
Settings Database contains the full set of configuration parameters 
that establish the behavior of DERs arranged in a single file, a so-
called utility-required profile, which is easily exchanged between 
parties or used across an entire region. For example, ISO-NE 
coordinated with Massachusetts utilities to establish a single New 
England Required Utility Profile applicable to all DERs in ISO-NE.\275\
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    \274\ See EPRI, DER Performance Capability and Functional 
Settings Database, Ver. 2.1 (2021), https://dersettings.epri.com/ 
(EPRI DER Settings Database) (a public web-based repository for the 
settings that utilities require for interconnection of DER. The 
database facilitates multiple DER setting files, and various 
metadata, e.g., DER types, IEEE standard 1547-specified performance 
categories, sizes, etc.).
    \275\ See Massachusetts Technical Standards Review Group, Common 
Technical Standards Manual, 16 n.9 (Dec. 22, 2022), https://www.mass.gov/doc/tsrg-common-guideline-2022-12-22/download; see also 
ISO-NE, Default New England Bulk System Area Settings, 1 (2022), 
https://www.mass.gov/doc/draft-in-progress-default-new-england-bulk-system-area-settings-requirement/download (as of June 1, 2022, these 
ISO-NE requirements apply to all DER applications. Additionally, DER 
projects must be compliant with the latest revision of IEEE-1547-
2018 (as amended by IEEE-1547a-2020)).
---------------------------------------------------------------------------

    148. The ability to efficiently store and exchange DER settings 
files is particularly useful to help DER developers and manufacturers 
to know the requirements that exist within each distribution provider's 
service territory. NERC's 2023 DER_A Model Guideline also references 
the EPRI DER Settings Database as a solution for readily exchanging and 
managing large amounts of IBR-DER settings used to build dynamic 
models.\276\ We encourage NERC's standard drafting team to consider the 
EPRI DER Settings Database as a useful resource in the standards 
development process when developing the necessary data exchange 
requirements for IBR-DERs that in the aggregate have a material impact 
on the Bulk-Power System.
---------------------------------------------------------------------------

    \276\ See 2023 DER_A Model Guideline at 18-19.

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[[Page 74275]]

    149. We acknowledge NERC's, AEU's, EPRI's, and ACP/SEIA's concerns 
about the verified IBR dynamic models being unavailable until 
completion of the facility interconnection process; however, in Order 
No. 2023 the Commission rejected a request to afford interconnection 
customers an extended period of time to meet the modeling 
requirements.\277\ Order No. 2023 requires an interconnection customer 
to provide the required models within the deadlines established in the 
pro forma LGIP and pro forma SGIP. Pursuant to those provisions, if the 
interconnection customer does not cure such a deficiency within the 10 
business day cure period, the interconnection request will be 
considered withdrawn pursuant to section 3.7 of the pro forma LGIP and 
section 1.3 of the pro forma SGIP. Order No. 2023 requires that the 
existing 10 business day cure period be consistently applied to all 
interconnection request deficiencies and that having an extended cure 
period for model deficiencies would potentially introduce delays in the 
interconnection process.\278\ Therefore, verified IBR dynamic models 
should be available prior to the completion of the facility 
interconnection process. Moreover, although the Reliability Standards 
will apply to a different (albeit overlapping) set of entities than 
Order No. 2023, we believe consistency is needed between the 
complimentary proceedings and therefore direct NERC to include in the 
new or modified Reliability Standards a similar model verification 
process timeline consistent with Order No. 2023 modeling deadline 
requirements.
---------------------------------------------------------------------------

    \277\ Order No. 2023, 184 FERC ] 61,054 at P 1666.
    \278\ Id.
---------------------------------------------------------------------------

    150. Regarding the IRC and SPP concerns about EMT model data 
availability and verification, as we decline to require the use of EMT 
models (as explained in section IV.C.1), we also decline to direct NERC 
to explicitly require EMT data and verified EMT models for the same 
reasons.
3. Validating and Updating System Models
    151. In the NOPR, the Commission explained that, after all IBR 
models are verified, Bulk-Power System planners and operators must 
validate and update transmission system models by comparing the 
provided data and resulting system models against actual system 
operational behavior. The Commission added that, while Reliability 
Standard MOD-033-2 requires data validation of the interconnection-wide 
model, the 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.\279\
---------------------------------------------------------------------------

    \279\ NOPR, 181 FERC ] 61,125 at P 40.
---------------------------------------------------------------------------

    152. The Commission therefore proposed to direct NERC to develop 
new or modified Reliability Standards that require planning 
coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities to validate, 
coordinate, and update in a timely manner the verified data and models 
of registered IBRs, unregistered IBRs, and IBR-DERs by comparing their 
data and resulting models against actual operational behavior. Further, 
the NOPR proposed this validation, coordination, and update directive 
to achieve and maintain necessary system models that accurately reflect 
performance and behaviors of registered IBRs and unregistered IBRs 
individually and in the aggregate, as well as performance and behaviors 
of IBR-DERs in the aggregate.\280\
---------------------------------------------------------------------------

    \280\ Id. P 85.
---------------------------------------------------------------------------

a. Comments
    153. NERC, NYSRC, CAISO, and AEP support the proposed directive for 
planning coordinators, transmission planners, reliability coordinators, 
transmission operators, and balancing authorities to validate, 
coordinate, and update transmission planning and transmission 
operations system models.\281\ NERC explains that its experience has 
shown that interconnection and long-term planning studies cannot 
identify possible performance issues without ``all of the relevant 
protections and controls being modeled and validated.'' \282\ ACP/SEIA 
explains that new models and validation should not be required for 
modifications that do not reflect any material electrical performance 
impact.\283\
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    \281\ NERC Initial Comments at 10; NYSRC Initial Comments at 1; 
CAISO Initial Comments at 30; AEP Initial Comments at 3.
    \282\ NERC Initial Comments at 13 (citing NERC and Texas RE, 
March 2022 Panhandle Wind Disturbance Report (Aug. 2022), https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf (Panhandle Disturbance Report) 
(covering the Texas Panhandle event (March 22, 2022)); Odessa 2022 
Disturbance Report).
    \283\ ACP/SEIA Initial Comments at 14.
---------------------------------------------------------------------------

    154. NERC agrees that transmission planners, planning coordinators, 
and reliability coordinators should have planning and operations models 
that represent all generation resources, including registered and 
unregistered IBRs, as well as aggregate representation of distributed 
energy resources (both synchronous and IBR).\284\ NERC explains that it 
has a number of projects underway in this area, including Project 2020-
06 (Verifications of Models and Data for Generators) and Project 2022-
04 (EMT Modeling). NERC states that additional projects may be needed 
for clarity and model accuracy in the future, including projects to 
address Commission directives included in a final rule in this 
proceeding. NERC explains that it is also planning to issue a modeling-
focused NERC Alert by the end of 2023 to better understand the extent 
of condition of modeling issues, which could inform future standards 
development efforts.\285\
---------------------------------------------------------------------------

    \284\ Id. at 10.
    \285\ NERC Initial Comments at 11.
---------------------------------------------------------------------------

    155. CAISO agrees that Bulk-Power System planners and operators 
need accurate planning and operational information so that their own 
models, together with the interconnection-wide models, reflect how IBRs 
operate in real world scenarios.\286\ APS asserts, similar to its 
comments regarding the difficulties of verifying models for IBR-DERs in 
the aggregate, that there is no feasible method (i.e., comparing actual 
to simulated events in a systematic way) to validate IBR-DER models 
system wide.\287\ In comparison, CAISO asserts that stakeholders could 
address the challenge of modeling IBR-DERs in the aggregate.\288\
---------------------------------------------------------------------------

    \286\ CAISO Initial Comments at 33.
    \287\ APS Initial Comments at 5.
    \288\ CAISO Initial Comments at 35-36.
---------------------------------------------------------------------------

b. Commission Determination
    156. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR 
proposal and direct NERC to submit new or modified Reliability 
Standards that require Bulk-Power System planners and operators to 
validate, coordinate, and update in a timely manner the system models 
by comparing all generator owner, transmission owner, and distribution 
provider verified IBR models (i.e., models of registered IBRs, 
unregistered IBRs, and IBR-DERs that in the aggregate have a material 
impact on the Bulk-Power System) and resulting system models against 
actual system operational behavior. NERC may implement this directive 
by modifying Reliability Standards MOD-026 and MOD-027 or by developing 
new Reliability Standards to establish requirements mandating a process 
to validate and keep up to date the system models. We find that this 
directive addresses ACP/SEIA's concerns comments regarding modification 
to and validation of models that do not reflect

[[Page 74276]]

any material electrical performance impact.
    157. We believe the development of new or modified Reliability 
Standards is an important corollary to NERC's ongoing effort to 
identify and register generator owners and operators of IBRs. Although 
NERC's registration changes will not at this time address IBR-DERs that 
in the aggregate have a material impact on the Bulk-Power System, we 
believe APS's concerns regarding system-wide model validation is 
addressed in NERC's Reliability Guidelines \289\ and through the use of 
the EPRI DER Settings Database. We recognize that some distribution 
providers may not be able to provide a precise set of modeling data and 
parameters that accurately represent IBR-DERs in the aggregate. For 
these situations, NERC has provided a technical means to estimate in 
aggregate the needed IBR-DER modeling data and parameters (i.e., for 
the DER_A model) in the IBR-DER Data Collection Guideline.\290\ 
Further, NERC's 2021 Aggregate DER Model Verification Guideline 
provides transmission planners and planning coordinators with tools and 
techniques that can be adapted for their specific systems to verify 
that aggregate DER models (i.e. DER_A models) are a suitable 
representation of these resources in planning assessments.\291\ 
Furthermore, for those areas with IBR-DERs in the aggregate that 
materially impact the reliable operation of the Bulk-Power System but 
do not have an associated registered distribution provider, we modify 
the NOPR proposal to direct NERC to determine the appropriate 
registered entity responsible for the data and parameters of IBR-DERs 
in the aggregate and to establish a process that requires identified 
registered entities to coordinate, validate, and keep up to date the 
system models.
---------------------------------------------------------------------------

    \289\ See generally IBR-DER Data Collection Guideline; Aggregate 
DER Model Verification Guideline.
    \290\ See generally IBR-DER Data Collection Guideline.
    \291\ See generally Aggregate DER Model Verification Guideline.
---------------------------------------------------------------------------

4. Need for Coordination When Creating and Updating Planning, 
Operational, and Interconnection-Wide Data and Models
    158. In the NOPR, the Commission preliminarily found that there is 
a ``coordination gap'' among registered entities that build and verify 
interconnection-wide models. The Commission noted that the functional 
entities and designees specified in Reliability Standards MOD-032-1 and 
MOD-033-2 are not required to work collaboratively to create 
interconnection-wide models that accurately reflect real-world 
interconnection-wide IBR performance and behavior. Therefore, the 
Commission proposed to direct NERC to develop new or modified 
Reliability Standards that require planning coordinators, transmission 
planners, reliability coordinators, transmission operators, and 
balancing authorities to validate, coordinate, and keep up to date in a 
timely manner the verified data and models of registered IBRs, 
unregistered IBRs, and IBR-DERs in the aggregate by comparing their 
data and resulting models against actual operational behavior to 
achieve and maintain necessary modeling accuracy of individual and 
aggregate (1) registered IBR performance and behaviors and (2) 
unregistered IBR performance and behaviors, as well as performance and 
behaviors of IBR-DERs in the aggregate.\292\
---------------------------------------------------------------------------

    \292\ NOPR, 181 FERC ] 61,125 at PP 84-85.
---------------------------------------------------------------------------

a. Comments
    159. NERC, CAISO, and AEP support the directives proposed in the 
NOPR that would require planning coordinators, transmission planners, 
reliability coordinators, transmission operators, and balancing 
authorities to coordinate when creating and updating planning, 
operations, and interconnection-wide models.\293\ For example, NERC 
agrees that there is a need for closer ties and coordination for 
Reliability Standards MOD-032 and MOD-033 activities to require that 
the models are tested more regularly and any modifications or updates 
to these models are provided to the relevant entities responsible for 
planning and operating the Bulk-Power System.\294\ Further, NERC states 
that Reliability Standards MOD-032 and MOD-033 should be updated to 
require a more comprehensive practice for system model validation 
requiring models to be rigorously tested for deficiencies and include 
minimum requirements for benchmarking events, such as by including a 
requirement that all plant models be validated through Reliability 
Standard MOD-033 activities.\295\
---------------------------------------------------------------------------

    \293\ NERC Initial Comments at 14; CAISO Initial Comments at 33; 
AEP Initial Comments at 1.
    \294\ NERC Initial Comments at 14.
    \295\ Id. at 14-15.
---------------------------------------------------------------------------

    160. CAISO supports the NOPR proposal and notes that, while there 
are technical, administrative, and compliance burdens associated with 
the imposition of additional new or modified IBR Reliability Standards, 
this initiative will provide a forum to consider ways to achieve an 
efficient and effective exchange of information among all relevant 
NERC-registered entities.\296\
---------------------------------------------------------------------------

    \296\ CAISO Initial Comments at 31-32.
---------------------------------------------------------------------------

b. Commission Determination
    161. Pursuant to section 215(d)(5) of the FPA, we modify the NOPR 
proposal to provide additional specificity to explain coordination and 
keep up to date in a timely manner the verified data and models of 
registered IBRs, unregistered IBRs, and IBR-DERs in the aggregate in 
the system models.\297\ Specifically, we direct NERC to develop new or 
modified Reliability Standards that require planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities to establish for each 
interconnection a uniform framework with modeling criteria, a 
registered modeling designee, and necessary data exchange requirements 
both between themselves and with the generator owners, transmission 
owners, and distribution providers to coordinate the creation of 
transmission planning, operations, and interconnection-wide models 
(i.e., system models) and the validation of each respective system 
model. Further, we direct NERC to include in the new or modified 
Reliability Standards a requirement for generator owners, transmission 
owners, and distribution providers to regularly update and communicate 
the verified data and models of registered IBRs, unregistered IBRs, and 
IBR-DERs by comparing their resulting models against actual operational 
behavior to achieve and maintain necessary modeling accuracy for 
inclusion of these resources in the system models. For those areas with 
IBR-DERs in the aggregate that have a material impact on the reliable 
operation of the Bulk-Power System but do not have an associated 
registered distribution provider, we modify the NOPR proposal to direct 
NERC to determine the appropriate registered entity responsible for the 
models of those IBR-DERs and to determine the registered entities 
responsible for updating, verifying, and coordinating models for IBR-
DERs in the aggregate to meet the system models directives. NERC may 
implement this directive by modifying Reliability Standards MOD-032-1 
and MOD-033-2 or by developing new Reliability Standards to establish 
requirements mandating an annual \298\ process to

[[Page 74277]]

coordinate, validate, and keep up-to-date the transmission planning, 
operations, and interconnection-wide models.
---------------------------------------------------------------------------

    \297\ NOPR, 181 FERC ] 61,125 at P 85.
    \298\ See Reliability Standard MOD-032-1 at 15 (explaining that 
``presently, the Eastern/Quebec and Texas Interconnections build 
seasonal cases on an annual basis, while the Western Interconnection 
builds cases on a continuous basis throughout the year'').
---------------------------------------------------------------------------

D. Planning and Operational Studies

    162. In the NOPR, the Commission preliminarily found that the 
currently effective Reliability Standards do not adequately require 
planning and operational studies to: (1) assess performance and 
behavior of both individual and aggregate registered IBRs and 
unregistered IBRs, as well as IBR-DERs that in the aggregate have a 
material impact on the Bulk-Power System; (2) have and use validated 
modeling and operational data for individual registered IBRs and 
unregistered IBRs, as well as modeling and operational data of IBR-DERs 
that in the aggregate have a material impact on the Bulk-Power System; 
and (3) account for the impacts of registered and unregistered IBRs 
individually and in the aggregate, as well as IBR-DERs that in the 
aggregate have a material impact on the Bulk-Power System, within and 
across planning and operational boundaries for normal operations and 
contingency event conditions. The Commission stated that planning and 
operational studies must use validated IBR modeling and operational 
data so that studies account for the actual behavior of both registered 
and unregistered IBRs individually and in the aggregate, as well as 
IBR-DERs that in the aggregate have a material impact on the Bulk-Power 
System.\299\
---------------------------------------------------------------------------

    \299\ NOPR, 181 FERC ] 61,125 at P 87.
---------------------------------------------------------------------------

    163. The Commission preliminarily found that the currently 
effective Reliability Standards do not result in accurate planning 
studies of Bulk-Power System performance over a broad spectrum of 
system conditions and following a wide range of probable contingencies 
that includes all resources.\300\ The Commission observed that 
inaccurate planning assessments may lead to false expectations that 
system performance requirements are met and may inadvertently mask 
potential reliability risks in planning and operations.\301\ The 
Commission proposed to direct NERC to submit for approval one or more 
new or modified Reliability Standards that would require planning 
coordinators and transmission planners to include in their planning 
assessments the study and evaluation of performance and behavior of 
registered and unregistered IBRs individually and in the aggregate, and 
IBR-DERs in the aggregate, under normal and contingency system 
conditions in their planning area. The Commission further proposed that 
the planning assessments include the study and evaluation of the ride 
through performance (e.g., tripping and momentary cessation conditions) 
of such IBRs in their planning area for stability studies on a 
comparable basis to synchronous generation resources.\302\
---------------------------------------------------------------------------

    \300\ Id. P 88.
    \301\ See NERC Glossary at 23 (defining planning assessment as a 
``Documented evaluation of future Transmission System performance 
and Corrective Action Plans to remedy identified deficiencies.'').
    \302\ NOPR, 181 FERC ] 61,125 at P 88.
---------------------------------------------------------------------------

    164. The Commission stated that the proposed new or modified 
Reliability Standards should also require planning coordinators and 
transmission planners to consider the behavior of registered and 
unregistered IBRs individually and in the aggregate, as well as IBR-
DERs in the aggregate, using planning models of their area and using 
interconnection-wide area planning models. Further, the Commission 
stated that the proposed new or modified Reliability Standards should 
also require planning coordinators and transmission planners to 
consider all IBR behaviors in adjacent and other planning areas that 
adversely impact a planning coordinator's or transmission planner's 
area during a disturbance event. The Commission explained that this is 
needed because registered IBRs, unregistered IBRs, and IBR-DERs tend to 
act in the aggregate over a wide area during such an event.\303\
---------------------------------------------------------------------------

    \303\ Id. (citing 2021 Solar PV Disturbances Report at v; Odessa 
2021 Disturbance Report at v; NERC, 1,200 MW Fault Induced Solar 
Photovoltaic Resource Interruption Disturbance Report, 2 (June 
2017), https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf (Blue Cut Fire Event Report) (covering the Blue Cut Fire event 
(August 16, 2016))); see also NOPR, 181 FERC ] 61,125 at P 88.
---------------------------------------------------------------------------

    165. The Commission preliminarily found that the Reliability 
Standards also do not require that the various operational studies 
(including operational planning analyses,\304\ real-time monitoring, 
real-time assessments,\305\ and other analysis functions) include all 
resources to adequately assess the performance of the Bulk-Power System 
for normal and contingency conditions.\306\ The Commission proposed to 
direct NERC to submit to the Commission for approval one or more new or 
modified Reliability Standards that would require reliability 
coordinators and transmission operators to include the performance and 
behavior of registered and unregistered IBRs both individually and in 
the aggregate, and IBR-DERs in the aggregate, (e.g., IBRs tripping or 
entering momentary cessation individually or in the aggregate) in their 
operational planning analysis, real-time monitoring, and real-time 
assessments, including non-bulk electric system data and external power 
system network data identified in their data specifications.\307\
---------------------------------------------------------------------------

    \304\ NERC defines operational planning analysis as an 
``evaluation of projected system conditions to assess anticipated 
(pre-Contingency) and potential (post-Contingency) conditions for 
next-day operations.'' The definition goes on to explain that the 
evaluation shall reflect ``applicable inputs including, but not 
limited to, load forecasts; generation output levels; Interchange; 
known Protection System and Special Protection System status or 
degradation; Transmission outages; generator outages; Facility 
Ratings; and identified phase angle and equipment limitations. 
(Operational Planning Analysis may be provided through internal 
systems or through third-party services).'' NERC Glossary at 22.
    \305\ NERC defines real-time assessment as an ``evaluation of 
system conditions using Real-time data to assess existing (pre-
Contingency) and potential (post-Contingency) operating 
conditions.'' The definition goes on to explain that the assessment 
shall reflect ``applicable inputs including, but not limited to: 
load, generation output levels, known Protection System and Special 
Protection System status or degradation, Transmission outages, 
generator outages, Interchange, Facility Ratings, and identified 
phase angle and equipment limitations. (Real-time Assessment may be 
provided through internal systems or through third-party 
services).'' Id. at 25.
    \306\ NOPR, 181 FERC ] 61,125 at P 89.
    \307\ Id. (citing Reliability Standard IRO-010-4, Requirement 
R1, pt. 1.1 and Reliability Standard TOP-003-5, Requirement R1, pt. 
1.1.).
---------------------------------------------------------------------------

    166. The Commission further proposed to direct NERC to submit to 
the Commission for approval one or more new or modified Reliability 
Standards that would require balancing authorities to include the 
performance and behavior of registered and unregistered IBRs 
individually and in the aggregate, as well as IBR-DERs that in the 
aggregate have a material impact on the Bulk-Power System, (e.g., 
resources tripping or entering momentary cessation individually or in 
the aggregate) in their operational analysis functions and real-time 
monitoring.\308\ The Commission explained that this proposal is 
consistent with the recommendations in the NERC DER Report, IBR 
Performance Guideline, IBR-DER Data Collection Guideline, and Loss of 
Solar Resources Alert II. The Commission stated that these reports 
indicate that a significant number of IBRs that have been involved in 
system disturbances were not adequately modeled in interconnection-wide 
models and tools used to study the performance and behavior of 
registered and unregistered IBRs individually and

[[Page 74278]]

in the aggregate, as well as IBR-DERs in the aggregate. Thus, the 
Commission found that neighboring operators may be unaware that faults 
in one operator's area can trigger controls actions and trip IBRs in 
another operator's area.\309\
---------------------------------------------------------------------------

    \308\ Id. (citing Reliability Standard TOP-003-5, Requirement 
R2, pt. 2.1.).
    \309\ Id. P 89.
---------------------------------------------------------------------------

1. Comments
    167. Commenters generally support a directive to require planning 
authorities to include data within their planning assessments to 
reflect expected actions of registered and unregistered IBRs 
individually and in the aggregate, as well as IBR-DERs in the 
aggregate, under normal and contingency system conditions.\310\ NERC 
also supports the proposed Commission directive to require transmission 
planners and planning coordinators to coordinate their studies with 
neighboring entities so that accurate models of registered and 
unregistered IBRs, as well as IBR-DERs in the aggregate, are 
represented appropriately for the operating conditions under 
study.\311\
---------------------------------------------------------------------------

    \310\ See, e.g., NERC Initial Comments at 18-20; AEP Initial 
Comments at 3; LADWP Reply Comments at 4; NYSRC Initial Comments at 
2; infiniRel Initial Comments at 2; CAISO initial Comments at 36; 
IRC initial Comments at 4; ISO-NE Initial Comments at 3-4.
    \311\ NERC Initial Comments at 19.
---------------------------------------------------------------------------

    168. NERC expects that any standard development project to address 
such a directive would need to include a wider set of operating 
conditions than simply ``peak'' and ``off-peak'' conditions. NERC 
explains that using production cost models or other simulation methods 
to identify operating conditions that could result in extreme stress on 
the grid could help inform planning assessments.\312\
---------------------------------------------------------------------------

    \312\ Id. at 18.
---------------------------------------------------------------------------

    169. NERC highlights that there may be gaps in the currently 
effective Reliability Standard TPL-001-5.1 planning assessments if they 
are performed without accurate IBR models and studies. NERC also points 
to its Project 2022-02 (Modifications to TPL-001-5.1 and MOD-032-1) as 
addressing some issues regarding appropriate inclusion of IBRs and DERs 
(IBR-DERs and synchronous DERs) in planning assessments but notes that 
additional modifications may be required to adequately address the 
issues presented in the NOPR. NERC also suggests enhancing the 
directive by identifying a wider set of operating conditions that would 
result in the most extreme expected grid stress conditions, both during 
on-peak load conditions but also off-peak, high renewables conditions 
(e.g., low inertia).\313\
---------------------------------------------------------------------------

    \313\ Id. at 18-19.
---------------------------------------------------------------------------

    170. Indicated Trade Associations note that NERC has several 
ongoing projects to improve the assessments of IBR performance as 
examples of the ongoing work to address IBR-related reliability 
concerns that should inform the NERC standard drafting teams that will 
work to address the directives in the final rule, once issued, 
including Project 2021-04 (Modifications to Reliability Standard PRC-
002) and Project 2022-02 (Modifications to Reliability Standards TPL-
001-5.1 and MOD-032-1). Indicated Trade Associations state that Project 
2021-04 would modify disturbance monitoring and reporting requirements 
to better assess resource performance of IBRs during disturbances, and 
Project 2022-02 is intended to clarify how IBRs are modeled and studied 
in planning assessments and to include distribution system IBR-DER data 
and models in steady state and stability contingency analysis.\314\
---------------------------------------------------------------------------

    \314\ Indicated Trade Associations Initial Comments at 7.
---------------------------------------------------------------------------

    171. LADWP generally supports including registered and unregistered 
IBRs in planning assessments, as well as assessments of IBR performance 
under normal and contingency system conditions, as critical to ensuring 
the reliable operation of the Bulk-Power System because during 
disturbance events IBRs tend to act in the aggregate over a widespread 
area. LADWP also supports including the study and evaluation of ride 
through performance for stability studies on a comparable basis to 
synchronous generation resources.\315\ LADWP offers that NERC could 
create a standardized method and criteria for performing additional 
performance and behavior analysis.\316\
---------------------------------------------------------------------------

    \315\ LADWP Reply Comments at 4.
    \316\ Id. at 4.
---------------------------------------------------------------------------

    172. IRC supports directives for planning and operational studies, 
asserting that the current standards do not grant them authority to 
require relevant entities to provide IBR-related data sufficient for 
accurate planning or operational studies.\317\ SPP encourages the 
Commission to ensure that registered IBRs provide evidence that they 
are included in planning coordinator and transmission planner planning 
assessments.\318\
---------------------------------------------------------------------------

    \317\ IRC Initial Comments at 5.
    \318\ SPP Initial Comments at 5.
---------------------------------------------------------------------------

    173. Commenters also support the Commission's proposed directive to 
require operational authorities to include data within their 
operational studies to reflect expected actions of registered and 
unregistered IBRs individually and in the aggregate, as well as IBR-
DERs in the aggregate, under normal and contingency system 
conditions.\319\ NERC supports coordinating models used by balancing 
authorities, transmission operators, and reliability coordinators 
across their footprints so that faults in one area do not result in 
unexpected tripping issues in another area.\320\
---------------------------------------------------------------------------

    \319\ NERC Initial Comments at 7; AEP Initial Comments at 3; 
NYSRC Initial Comments at 2; infiniRel Initial Comments at 2; CAISO 
Initial Comments at 37; IRC Initial Comments at 4; ISO-NE Reply 
Comments at 3.
    \320\ NERC Initial Comments at 20.
---------------------------------------------------------------------------

2. Commission Determination
    174. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR 
proposal and direct NERC to develop and submit to the Commission for 
approval new or modified Reliability Standards that require planning 
coordinators and transmission planners to include in their planning 
assessments the study and evaluation of performance and behavior of 
registered and unregistered IBRs individually and in the aggregate, as 
well as IBR-DERs in the aggregate, under normal and contingency system 
conditions in their planning area. These Reliability Standards should 
require planning coordinators and transmission planners to include in 
their planning assessments the study and evaluation of the ride through 
performance (e.g., tripping and momentary cessation conditions) of IBRs 
in their planning area for stability studies on a comparable basis to 
synchronous generation resources. The new or modified Reliability 
Standards should also require planning coordinators and transmission 
planners to study the Bulk-Power System reliability impacts of 
registered and unregistered IBRs individually and in the aggregate, as 
well as IBR-DERs in the aggregate, in their planning models of their 
area and in their interconnection-wide area planning models. Further, 
the new or modified Reliability Standards should also require planning 
coordinators and transmission planners to study the Bulk-Power System 
reliability impacts of registered and unregistered IBRs individually 
and in the aggregate, as well as IBR-DERs in the aggregate, in adjacent 
and other planning areas that adversely impacts a planning 
coordinator's or transmission planner's area during a disturbance 
event.
    175. Regarding NERC's recommendations to clarify the types of 
steady-state and dynamic grid conditions to include in planning 
studies, we agree that it is important to ensure performance during 
periods of grid stress. Accordingly, we direct

[[Page 74279]]

NERC to consider in its standards development process whether to 
include in new or modified Reliability Standards a requirement that 
planning coordinators and transmission planners include a wide set of 
grid stress performance conditions (i.e., both typical and extreme 
conditions) in planning assessments.\321\ Likewise, with regards to 
NERC's comments related to on-peak and off-peak studies, we direct NERC 
to consider in the standards development process whether to require 
planning coordinators and transmission planners to account in planning 
assessments for both on-peak and off-peak conditions, normal and 
abnormal (contingency) conditions with high penetration levels of IBRs 
(i.e., registered IBRs, unregistered IBRs, and IBR-DERs that in the 
aggregate have a material impact on the Bulk-Power System), and normal 
and abnormal conditions with low inertia. While we agree with NERC that 
the above suggestions have merit, we believe that vetting in the 
standards development process is preferable to determine whether such 
provisions are beneficial and the scope and language of such 
provisions. Accordingly, we simply direct NERC to consider these 
matters without directing a specific outcome.
---------------------------------------------------------------------------

    \321\ NOPR, 181 FERC ] 61,125 at P 88 & n.164 (citing several 
NERC disturbance reports that identifies the potential adverse 
impact of registered IBRs, unregistered IBRs, and IBR-DERs acting in 
the aggregate in various system conditions over a wide area).
---------------------------------------------------------------------------

    176. We adopt the NOPR proposal and direct NERC to submit to the 
Commission for approval one or more new or modified Reliability 
Standards that require reliability coordinators and transmission 
operators to include the performance and behavior of registered and 
unregistered IBRs individually and in the aggregate, as well as IBR-
DERs in the aggregate, (e.g., IBRs tripping or entering momentary 
cessation individually or in the aggregate) in their operational 
planning analyses, real-time monitoring, and real-time assessments, 
including non-bulk electric system data and external power system 
network data identified in their data specifications.\322\ Further, we 
agree with commenters and direct NERC to submit to the Commission for 
approval new or modified Reliability Standards requiring reliability 
coordinators and transmission operators, when performing operational 
studies, as well as operational planning analyses, real-time 
monitoring, real-time assessments, and other analyses, to include in 
these studies all generation resources (i.e., all generation resources 
including all IBRs) necessary to adequately assess the performance of 
the Bulk-Power System for normal and contingency conditions.\323\
---------------------------------------------------------------------------

    \322\ See, e.g., Reliability Standard IRO-010-4, Requirement R1, 
pt. 1.1 (stating ``[a] list of data and information needed by the 
Reliability Coordinator to support its Operational Planning 
Analyses, Real-time monitoring, and Real-time Assessments. . .'') 
and Reliability Standard TOP-003-5, Requirement R1, pt. 1.1 (stating 
``[a] list of data and information needed by the Transmission 
Operator to support its Operational Planning Analyses, Real-time 
monitoring, and Real-time Assessments . . . '').
    \323\ NOPR, 181 FERC ] 61,125 at P 52.
---------------------------------------------------------------------------

    177. We adopt the NOPR proposal and direct NERC to submit to the 
Commission for approval one or more new or modified Reliability 
Standards that require balancing authorities to include the performance 
and behavior of registered and unregistered IBRs individually and in 
the aggregate, as well as IBR-DERs that in the aggregate have a 
material impact on the Bulk-Power System, (e.g., resources tripping or 
entering momentary cessation individually or in the aggregate) in their 
operational analysis functions and real-time monitoring to support the 
reliable operation of the Bulk-Power System during normal and 
contingency conditions.\324\
---------------------------------------------------------------------------

    \324\ See, e.g., Reliability Standard TOP-003-5, Requirement R2, 
part 2.1 (stating ``[a] list of data and information needed by the 
Balancing Authority to support its analysis functions and Real-time 
monitoring'').
---------------------------------------------------------------------------

E. Performance Requirements

1. Registered IBR Frequency and Voltage Ride Through Requirements
    178. In the NOPR, the Commission preliminarily found that the 
Reliability Standards should require registered IBRs to ride through 
system disturbances to support essential reliability services.\325\ 
Without the availability of essential reliability services, the 
Commission explained that the system would experience instability, 
voltage collapse, or uncontrolled separation. Therefore, the Commission 
proposed to direct NERC to develop new or modified Reliability 
Standards that would require registered IBR facilities to ride through 
system frequency and voltage disturbances where technologically 
feasible. The Commission stated that ride through performance during 
system disturbances is necessary for registered IBRs to support 
essential reliability services.
---------------------------------------------------------------------------

    \325\ NOPR, 181 FERC ] 61,125 at P 90.
---------------------------------------------------------------------------

    179. The Commission proposed that the new or modified Reliability 
Standards should require registered IBRs to continue to produce power 
and perform frequency support during system disturbances. The 
Commission proposed to direct NERC to develop new or modified 
Reliability Standards that would require IBR generator owners and 
operators to use appropriate settings (i.e., inverter, plant 
controller, and protection) that: (1) will assure frequency ride 
through during system disturbances and that would permit IBR tripping 
only to protect the IBR equipment; and (2) allow for voltage ride 
through during system disturbances and would permit IBR tripping only 
when necessary to protect the IBR equipment.\326\ In the NOPR, the 
Commission also explained that any new or modified Reliability 
Standards should require generator owners of IBR facilities to prohibit 
momentary cessation in the no-trip zone during disturbances by using 
appropriate and coordinated protection and controls settings.\327\
---------------------------------------------------------------------------

    \326\ Id. PP 93-95.
    \327\ Id. P 94.
---------------------------------------------------------------------------

    180. The Commission proposed to direct NERC to develop new or 
modified Reliability Standards that clearly address and document the 
technical capabilities of, and differences between, registered IBRs and 
synchronous generation resources so that registered IBRs will support 
these essential reliability services.\328\
---------------------------------------------------------------------------

    \328\ Id. P 90.
---------------------------------------------------------------------------

a. Comments
    181. Commenters generally support the Commission's proposed 
directives to require IBRs to use appropriate settings that will assure 
ride through during system disturbances.\329\ NERC supports the 
development of a comprehensive, performance-based ride through standard 
to assure future grid reliability.\330\ Indicated Trade Associations 
and APS agree that the current Reliability Standards do not have IBR-
specific performance requirements necessary to ensure the reliable 
operation of the Bulk-Power System.\331\ IRC asserts that there should 
be requirements for all IBRs to act to support Bulk-Power System 
reliability during disturbances.\332\ AEU highlights the ability of 
IBRs to deliver ancillary services such as frequency control.\333\ 
CAISO encourages the Commission to move forward in directing NERC to

[[Page 74280]]

establish a minimum standard to require all IBRs to ride through 
frequency disturbances \334\ and states that, in its experience, modern 
inverters can meet these standards without substantial costs or 
hardships.\335\
---------------------------------------------------------------------------

    \329\ NERC, AEU, ACP/SEIA, AEP, CAISO, Indicated Trade 
Associations, ISO-NE, IRC, NYSRC, Ohio FEA, SCE/PG&E, and SPP all 
indicated support for Reliability Standards for IBR performance 
requirements.
    \330\ NERC Initial Comments at 21.
    \331\ 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).
    \332\ IRC Initial Comments at 5.
    \333\ AEU Initial Comments at 2.
    \334\ CAISO Initial Comments at 11.
    \335\ Id. at 7 (citing Cal. Indep. Sys. Operator Corp., 168 FERC 
] 61,003, at P 18 n.23 (2019) (noting that, based on input from 
developers and manufacturers of IBRs, ``CAISO believes that the cost 
of meeting these requirements will be de minimis'').
---------------------------------------------------------------------------

    182. NERC, ACP/SEIA, Indicated Trade Associations, SCE/PG&E, and 
SPP all point to NERC Project 2020-02 (Modifications to PRC-024 
(Generator Ride-through)) as the best means to address ride through 
performance of IBRs. NERC explains that it has already updated the 
scope of its existing Project 2020-02 to require ride through 
performance for all generation resources (not just IBRs).\336\ ACP/
SEIA, SPP, and Indicated Trade Associations note that this project is 
addressing performance standards for all resource types, including 
IBRs.\337\ SCE/PG&E explain that Project 2020-02 aims to reduce the 
type of abnormal performance reliability impacts to the Bulk-Power 
System that NERC has described in its disturbance reports.\338\
---------------------------------------------------------------------------

    \336\ See, e.g., NERC Initial Comments at 22.
    \337\ ACP/SEIA Initial Comments at 7-8; SPP Initial Comments at 
6; Indicated Trade Associations Initial Comments at 8.
    \338\ SCE/PG&E Initial Comments at 5.
---------------------------------------------------------------------------

    183. ACP/SEIA agree with the Commission's prioritization to require 
NERC to develop IBR ride through Reliability Standards proposed in the 
NOPR, although they caution that, depending on local factors, different 
transmission operators may require different ride through performance 
of generators.\339\ ACP/SEIA recommend that NERC continue with Project 
2020-02 to modify Reliability Standard PRC-024-3 so that it becomes a 
ride through performance standard for both IBR and synchronous 
resources, which would both save time and provide a technology-neutral 
solution in addressing the full scope of the ride through risk facing 
the Bulk-Power System.\340\ ACP/SEIA also ask the Commission to clarify 
in the final rule that the new or modified Reliability Standards on 
ride through should not require generators to maintain real power 
output at pre-disturbance levels, noting that it is neither feasible 
nor desirable for generators to maintain real power output at pre-
disturbance levels in many instances. ACP/SEIA suggest that the 
directive instead require registered IBRs to continue to inject current 
during system disturbances.\341\
---------------------------------------------------------------------------

    \339\ ACP/SEIA Initial Comments at 1-2.
    \340\ Id. at 10-11.
    \341\ Id. at 7.
---------------------------------------------------------------------------

    184. EPRI notes that maintaining current at the pre-disturbance 
level during a disturbance may not be practical, needed, or aligned 
with IEEE 2800-2022 or other international requirements.\342\ EPRI 
explains that Commission directives to NERC to develop Reliability 
Standards for IBR ride-through capability and performance requirements 
could refer to IEEE 2800-2022 standards in accordance with good utility 
practice as examples of technical minimum requirements.\343\
---------------------------------------------------------------------------

    \342\ EPRI Initial Comments at 25.
    \343\ Id. at 5.
---------------------------------------------------------------------------

    185. NERC supports the Commission's proposed directive to require 
frequency and voltage ride through during system disturbances.\344\ 
NERC explains that its updated scope for Project 2020-02 will require 
ride through performance for all generation resources and will include: 
(1) no momentary cessation in the no trip zone specified, (2) no 
tripping on instantaneous frequency and voltage deviations, (3) no 
tripping due to phase lock loop loss within acceptable bounds, (4) no 
tripping due to DC bus protection and overcurrent protection, and (5) 
no tripping for unbalanced faults.\345\ AEU states that IBRs are not 
only capable of delivering voltage regulation but, in some cases, can 
provide ancillary services ``more quickly and accurately than 
conventional technologies.'' \346\
---------------------------------------------------------------------------

    \344\ NERC Initial Comments at 22.
    \345\ Id.
    \346\ AEU Initial Comments at 3.
---------------------------------------------------------------------------

    186. Indicated Trade Associations point to NERC Project 2021-02 
Modifications to VAR-002-4.1 (Generator Operation for Maintaining 
Network Voltage Schedules) as an existing standards project that is 
working to modify the currently effective Reliability Standard to 
specify and ensure the reactive support and voltage control obligations 
of IBRs in accordance with their capability.\347\ ISO-NE notes that if 
the Commission restricts its directive to only registered IBR generator 
owners and operators, it will leave out the majority of IBRs within New 
England.\348\
---------------------------------------------------------------------------

    \347\ Indicated Trade Associations Initial Comments at 8.
    \348\ ISO-NE Initial Comments at 5.
---------------------------------------------------------------------------

    187. UNIFI notes that newer technologies such as grid-forming IBRs 
have different behavioral responses to disturbances on the grid and 
offers an initial set of specifications for grid-forming IBRs that 
could be used as uniform technical requirements for the 
interconnection, integration, and interoperability of grid-forming 
IBRs.\349\
---------------------------------------------------------------------------

    \349\ UNIFI Initial Comments at 1.
---------------------------------------------------------------------------

    188. ACP/SEIA recommend that the Commission direct NERC to either 
exempt existing equipment that cannot meet the new or modified 
Reliability Standards or specify that the new or modified Reliability 
Standards should require compliance only to the extent it is possible 
with the equipment's current capabilities. ACP/SEIA suggest that any 
exemption should cover generators that cannot meet the ride-through 
requirements with updates to their inverter and control settings, and 
thus would require replacement of that equipment. ACP/SEIA point to 
Reliability Standard PRC-024-3 as an example of an exemption that is 
already included.\350\
---------------------------------------------------------------------------

    \350\ ACP/SEIA Initial Comments at 9. See also id. at 8 
(Reliability Standard PRC-024-3, Requirement R3 requires generator 
owners to document each known regulatory or equipment limitation 
that prevents the resource from meeting protection settings 
criteria).
---------------------------------------------------------------------------

    189. CAISO recommends that the Commission support NERC in 
identifying technical changes or equipment modifications that could be 
made to existing IBRs incapable of disabling momentary cessation, such 
as eliminating plant-level controller interactions.\351\ NYSRC 
disagrees that there should be an exception for existing IBRs and 
recommends that the Commission delineate an amount of time for IBR 
facilities to either demonstrate compliance or institute their own 
mitigation measures.\352\ NYSRC and ISO-NE ask the Commission to 
clarify that the performance requirements directed as part of the final 
rule would apply to both new and existing IBRs.\353\
---------------------------------------------------------------------------

    \351\ CAISO Initial Comments at 17 (quoting 2021 Solar PV 
Disturbances Report at 14).
    \352\ NYSRC Initial Comments at 4.
    \353\ Id.; ISO-NE Initial Comments at 6.
---------------------------------------------------------------------------

b. Commission Determination
    190. 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 
use appropriate settings (i.e., inverter, plant controller, and 
protection) to ride through frequency and voltage system disturbances 
and that permit IBR tripping only to protect the IBR equipment in 
scenarios similar to when synchronous generation resources use tripping 
as protection from internal faults. The new or modified Reliability 
Standards must require registered IBRs to continue to inject current 
and perform frequency

[[Page 74281]]

support during a Bulk-Power System disturbance. Any new or modified 
Reliability Standard must also require registered IBR generator owners 
and operators to prohibit momentary cessation in the no-trip zone 
during disturbances. NERC must submit new or modified Reliability 
Standards that establish IBR performance requirements, including 
requirements addressing frequency and voltage ride through, post-
disturbance ramp rates, phase lock loop synchronization, and other 
known causes of IBR tripping or momentary cessation.\354\ This 
directive is supported by the comments, as well as the recommendations 
from multiple event reports, including the Blue Cut Fire Event 
Report,\355\ the Odessa 2021 Disturbance Report,\356\ and the 2021 
Solar PV Disturbances Report.\357\ The directive is also consistent 
with NERC's comments and the March 2023 Alert language.\358\ 
Additionally, in response to requests by ISO-NE and NYSRC for the 
Commission to clarify that the performance requirements directed as 
part of the final rule would apply to both new and existing IBRs, we 
further clarify that all performance requirement directives apply to 
new and existing registered IBRs.
---------------------------------------------------------------------------

    \354\ See infra P 209.
    \355\ Blue Cut Fire Event Report at 11-13.
    \356\ Odessa 2021 Disturbance Report at vii, 12-13.
    \357\ 2021 Solar PV Disturbances Report at vii, 15, 31.
    \358\ March 2023 Alert at 4-5 (recommending that industry set 
fault ride through parameters ``to maximize active current delivery 
during the fault and post-fault periods'' and to ``not artificially 
limit dynamic reactive power capability delivered to the point of 
interconnection during normal operations and [Bulk-Power System] 
disturbances.'').
---------------------------------------------------------------------------

    191. In response to ACP/SEIA's comments, we clarify that we are not 
directing NERC to modify the currently effective Reliability Standards 
to require registered IBRs to maintain real power output during system 
disturbances. Rather, the new or modified Reliability Standards must 
require registered IBRs to continue to inject current during system 
disturbances. We note that Order No. 2023 requires non-synchronous 
resources to ensure that, within any physical limitations of the 
generating facility, its control and protection settings are configured 
or set to ``continue active power production during disturbance and 
post disturbance periods at pre-disturbance levels unless providing 
primary frequency response or fast frequency response'' \359\ The ride 
through directive in this final action differs from the ride-through 
requirements established in Order No. 2023 because the Reliability 
Standards apply more comprehensively and are enforced differently. 
While ride through requirements set forth in Reliability Standards will 
apply to both existing IBRs and newly interconnecting IBRs, the ride 
through requirements of the pro forma LGIA and pro forma SGIA 
established in Order No. 2023 apply only to newly interconnecting IBRs. 
Moreover, any ride through requirements established through the 
Reliability Standards would be enforceable by NERC, its Registered 
Entities, and the Commission through the Reliability Standard 
enforcement process.
---------------------------------------------------------------------------

    \359\ Order No. 2023, 184 FERC ] 61,054 at P 1715.
---------------------------------------------------------------------------

    192. We believe that, through its standard development process, 
NERC is best positioned, with input from stakeholders to determine 
specific IBRs performance requirements during ride through conditions, 
such as type (e.g., real current and/or reactive current) and magnitude 
of current. NERC should use its discretion to determine the appropriate 
technical requirements needed to ensure frequency and voltage ride 
through by registered IBRs during its standards development process. In 
response to comments regarding NERC Project 2020-02 Modifications to 
PRC-024 (Generator Ride-through) and its updated scope to address IBR 
ride through performance,\360\ we discuss this suggestion further in 
section IV.F, which requires that NERC's informational filing discuss 
how it is considering standard development projects already underway 
that may satisfy the directives in this final action.
---------------------------------------------------------------------------

    \360\ See, e.g., NERC Initial Comments at 22; Indicated Trades 
Associations Initial Comments at 8.
---------------------------------------------------------------------------

    193. Regarding ACP/SEIA's request for an explicit exemption for 
existing IBRs with equipment limitations, we agree that a subset of 
existing registered IBRs--typically older IBR technology with hardware 
that needs to be physically replaced and whose settings and 
configurations cannot be modified using software updates--may be unable 
to implement the voltage ride though performance requirements directed 
herein. Therefore, we direct NERC through its standard development 
process to determine whether the new or modified Reliability Standards 
should provide for a limited and documented exemption for certain 
registered IBRs from voltage ride through performance requirements. Any 
such exemption should be only for voltage ride-through performance for 
those existing IBRs that are unable to modify their coordinated 
protection and control settings to meet the requirements without 
physical modification of the IBRs' equipment. Further, we direct NERC 
to ensure that any such exemption would be applicable for only existing 
equipment that is unable to meet voltage ride-through performance. When 
such existing equipment is replaced, the exemption would no longer 
apply, and the new equipment must comply with the appropriate IBR 
performance requirements specified in the Reliability Standards (e.g., 
voltage and frequency ride through, phase lock loop, ramp rates, etc.). 
The concern that there are existing registered IBRs unable to meet 
voltage ride through requirements should diminish over time as legacy 
IBRs are replaced with or upgraded to newer IBR technology that does 
not require such accommodation.\361\ We encourage NERC's standard 
drafting team to consider currently effective Reliability Standard PRC-
024-3, Requirement R3 as an example for establishing registered IBR 
technology exemptions.\362\ Finally, we direct NERC, through its 
standard development process, to require the limited and documented 
exemption list (i.e., IBR generator owner and operator exemptions) to 
be communicated with their respective Bulk-Power System planners and 
operators (e.g., the IBR generator owner's or operator's planning 
coordinator, transmission planner, reliability coordinator, 
transmission operator, and balancing authority). The Bulk-Power System 
planners and operators' mitigation activity directives are discussed 
below in section IV.E.2.
---------------------------------------------------------------------------

    \361\ See generally 2021 Solar PV Disturbances Report at 14 
(discussing momentary cessation from legacy facilities that cannot 
eliminate its use).
    \362\ Reliability Standard PRC-024-3, Requirement R3 (explaining 
that ``each Generator Owner shall document each known regulatory or 
equipment limitation that prevents an applicable generating 
resource(s) with frequency or voltage protection from meeting the 
protection setting criteria in Requirements R1 or R2, including (but 
not limited to) study results, experience from an actual event, or 
manufacturer's advice.'').
---------------------------------------------------------------------------

    194. In response to ISO-NE's concern that applying ride through 
performance requirements only to registered IBRs means that the 
requirements would not apply to the vast majority of IBR capacity in 
New England, the Commission has already directed NERC to register IBRs 
that materially impact reliability and believes that NERC's workplan 
approved in the Order Approving Workplan will be a step towards 
mitigating ISO-NE's concern about unregistered IBRs.\363\
---------------------------------------------------------------------------

    \363\ See Order Approving Workplan, 183 FERC ] 61,116 at P 32 
(explaining that NERC asserts that its work plan would result in 
approximately 98 percent of Bulk-Power System-connected IBRs being 
subject to applicable Reliability Standards).
---------------------------------------------------------------------------

    195. Although EPRI asserts that IEEE standards specify technical 
minimum

[[Page 74282]]

capability and performance requirements that could be referenced as 
examples of good utility practice,\364\ NERC's comments indicate that 
currently effective Reliability Standard PRC-024-3, as well as the re-
scoped Project 2020-02 (Modifications to PRC-024 (Generator Ride-
through)), differ from IEEE standards in that both the currently 
effective Reliability Standard and re-scoped PRC-024 project disallow 
momentary cessation within the no trip zone, while IEEE-2800-2022 would 
allow momentary cessation under certain conditions.\365\ As the record 
in this proceeding provides no basis to conclude that the performance 
requirements of IEEE 2800-2022 are preferable to NERC's or would 
adequately address the reliability concerns discussed in this final 
action, we decline to direct NERC to specifically reference IEEE 
standards in its new or modified Reliability Standards. Rather, NERC 
has the discretion to consider during its standards development process 
whether and how to reference IEEE standards in the new or modified 
Reliability Standards.
---------------------------------------------------------------------------

    \364\ See, e.g., EPRI Initial Comments at 5; see also id. at 8 
(proposing generally that the Reliability Standards should consider 
using the precise language and definitions as published in the 
industry standards and aligning requirements with leading 
international practice and grid codes).
    \365\ See NERC Initial Comments at 22 n.39 (explaining that 
``[a] notable caveat is that IEEE 2800 allows momentary cessation 
(referred to as current blocking) at very low voltages (i.e., <0.1 
pu voltage). This nuance could be addressed by the standard drafting 
team and should be considered by regulatory bodies to ensure 
alignment.'').
---------------------------------------------------------------------------

2. Bulk-Power System Planners and Operators Voltage Ride Through 
Mitigation Activities
    196. In the NOPR, the Commission acknowledged that some registered 
generator owners and operators of IBRs currently in operation may be 
unable to prohibit momentary cessation in the no-trip zone during 
disturbances by using appropriate and coordinated protection and 
controls settings.\366\ For such scenarios, the Commission proposed to 
direct NERC to require Bulk-Power System planners and operators to 
implement mitigation activities that may be needed to address any 
reliability impact to the Bulk-Power System posed by these existing 
facilities.\367\
---------------------------------------------------------------------------

    \366\ See, e.g., 2021 Solar PV Disturbances Report at 14 
(discussing technical limitations of legacy IBRs related to voltage 
control and momentary cessation).
    \367\ NOPR, 181 FERC ] 61,125 at PP 94-95.
---------------------------------------------------------------------------

a. Comments
    197. NYSRC raises concerns with the Commission's proposal because 
allowing an exception for legacy registered IBRs would mean that 
transmission owners and operators would be responsible for mitigating 
an event consisting of an unknown number of IBRs disconnecting from the 
system at any time in the future, in an unanticipated manner.\368\ 
NYSRC asserts that requiring transmission planners and operators to 
ensure there are mitigation strategies for scenarios where existing 
IBRs are unable to meet performance requirements would be infeasible, 
as they would need to plan for and address an event consisting of an 
unknown number of IBRs disconnecting at any time.\369\
---------------------------------------------------------------------------

    \368\ NYSRC Initial Comments at 4.
    \369\ Id.
---------------------------------------------------------------------------

    198. Indicated Trade Associations disagree with the Commission's 
proposal to require transmission planners and operators to mitigate 
instances in which IBRs are incapable of prohibiting momentary 
cessation in the no-trip zone during disturbances, asserting that such 
a requirement should be solely the responsibility of registered 
generator owners.\370\ Indicated Trade Associations also ask the 
Commission to clarify what it means by an ``operator'' being 
responsible for mitigating events.
---------------------------------------------------------------------------

    \370\ Indicated Trade Associations Initial Comments at 8.
---------------------------------------------------------------------------

b. Commission Determination
    199. Pursuant to section 215(d)(5) of the FPA, we modify the NOPR 
proposal. To the extent NERC determines that a limited and documented 
exemption for those registered IBRs currently in operation and unable 
to meet voltage ride-through requirements is appropriate due to their 
inability to modify their coordinated protection and control 
settings,\371\ we direct NERC to develop new or modified Reliability 
Standards to mitigate the reliability impacts to the Bulk-Power System 
of such an exemption. As NERC will consider the reliability impacts to 
the Bulk-Power System caused by an such exemption, we believe that the 
concerns raised by NYSRC and Indicated Trade Associations on the 
appropriate registered entity responsible for implementing the 
mitigation activities, and the nature of such mitigation, should be 
addressed in the NERC standards development process.
---------------------------------------------------------------------------

    \371\ See supra section IV.E.1.
---------------------------------------------------------------------------

3. Post-Disturbance IBR Ramp Rate Interactions and Phase Lock Loop 
Synchronization
    200. In the NOPR, the Commission proposed to direct NERC to develop 
new or modified Reliability Standards to address other registered IBR 
performance and operational characteristics that can affect the 
reliable operation of the Bulk-Power System, namely, ramp rate 
interactions and phase lock loop synchronization.\372\ The Commission 
stated that the proposed directives would improve the reliable 
operation of the Bulk-Power System by helping to avoid instability, 
voltage collapse, uncontrolled separation, or islanding.\373\
---------------------------------------------------------------------------

    \372\ NOPR, 181 FERC ] 61,125 at P 91.
    \373\ Id. P 92.
---------------------------------------------------------------------------

    201. The Commission proposed to direct NERC to ensure that post-
disturbance ramp rates for registered IBRs are not restricted or do not 
artificially interfere with the IBR returning to a pre-disturbance 
output level in a quick and stable manner after a Bulk-Power System 
fault event.\374\ Furthermore, the Commission proposed to direct NERC 
to require that IBRs ride through any conditions not addressed by the 
proposed new or modified Reliability Standards covering frequency or 
voltage ride through, including phase lock loop loss of 
synchronism.\375\
---------------------------------------------------------------------------

    \374\ Id. P 96. See Canyon 2 Fire Event Report at 11 (stating 
that ``[e]xisting inverters where momentary cessation cannot be 
effectively eliminated should not be impeded from restoring current 
injection following momentary cessation. Active current injection 
should not be restricted by a plant-level controller or other slow 
ramp rate limits. Resources with this interaction should remediate 
the issue in close coordination with their [balancing authority] and 
inverter manufacturers to ensure that ramp rates are still enabled 
appropriately to control gen-load balance but not applied to 
restoring output following momentary cessation.'').
    \375\ Id. P 97. See Canyon 2 Fire Event Report at vi (explaining 
that inverters should ride through momentary loss of synchronism 
during Bulk-Power System events, such as faults. Inverters riding 
through these disturbances should ``continue to inject current into 
the grid and, at a minimum, lock the [phase lock loop] to the last 
synchronized point and continue injecting current to the [Bulk-Power 
System] at that calculated phase until the [phase lock loop] can 
regain synchronism upon fault clearing'').
---------------------------------------------------------------------------

    202. Further, the Commission proposed to direct that the 
Reliability Standards obligate generator owners to communicate to the 
relevant planning coordinators, transmission planners, reliability 
coordinators, transmission operators, and balancing authorities the 
actual post-disturbance ramp rates and the ramp rates set to meet 
expected dispatch levels (i.e., generation-load balance). The 
Commission explained that the proposed new or modified Reliability 
Standards should account for the technical differences between IBRs and 
synchronous generation resources, such as IBRs' faster control 
capability to

[[Page 74283]]

ramp power output down or up when capacity is available.\376\
---------------------------------------------------------------------------

    \376\ NOPR, 181 FERC ] 61,125 at P 96.
---------------------------------------------------------------------------

    203. The Commission also explained that the currently effective 
Reliability Standards do not require that all generation resources 
maintain voltage phase angle synchronization with the Bulk-Power System 
grid voltage during a system disturbance.\377\ The Commission proposed 
that any new or modified Reliability Standards should require IBRs to 
ride through momentary loss of synchronism during Bulk-Power System 
disturbances and require IBRs to continue to inject current into the 
Bulk-Power System at pre-disturbance levels during a disturbance.\378\
---------------------------------------------------------------------------

    \377\ Id. P 97.
    \378\ Id.
---------------------------------------------------------------------------

a. Comments
    204. NERC, AEP, CAISO, IRC, and NYSRC support the proposed 
directive to address post-disturbance IBR ramp rate interactions and 
phase lock loop synchronization.\379\ NERC explains that it is 
considering requirements amending the project scope for Project 2020-02 
Modifications to PRC-024 (Generator Ride-through) to include 
consideration of post-fault recovery times, ramp rate interactions, or 
the injection of certain levels of currents (and powers) during grid 
disturbances, and to include requirements that disallow phase lock loop 
loss of synchronism and other phase angle-based tripping within 
acceptable bounds.\380\
---------------------------------------------------------------------------

    \379\ NERC Initial Comments at 5; AEP Initial Comments at 5; 
CAISO Initial Comments at 1; IRC Initial Comments at 5; NYSRC 
Initial Comments at 1.
    \380\ NERC Initial Comments at 22.
---------------------------------------------------------------------------

    205. ACP/SEIA do not believe that IBRs can inject current 
accurately when synchronism is lost and assert that in those cases IBRs 
would blindly provide pre-fault current, which would not be desirable 
for grid stability.\381\ ACP/SEIA recommend revising the language of 
the directive to require generators to maintain synchronism where 
possible and continue to inject current to support system 
stability.\382\
---------------------------------------------------------------------------

    \381\ ACP/SEIA Initial Comments at 8.
    \382\ Id.
---------------------------------------------------------------------------

    206. Although SPP agrees with proposed directives related to ramp 
rate interactions and phase lock loop synchronization, SPP requests 
that the Commission include in the final rule a consideration of the 
IEEE 2800-2022 standard. SPP recommends that the Commission direct an 
analysis of the interrelationship or overlap between the IEEE standards 
and any new or modified Reliability Standards.\383\
---------------------------------------------------------------------------

    \383\ SPP Initial Comments at 4.
---------------------------------------------------------------------------

    207. EPRI suggests that the Commission direct NERC to develop new 
or modified Reliability Standards using comprehensive and holistic ride 
through capability and performance requirements instead of explicitly 
mentioning causes of trip (i.e., loss of phase lock loop synchronism in 
this case) or causes of slow recovery (i.e., slow ramp rate), which may 
leave out other causes.\384\
---------------------------------------------------------------------------

    \384\ EPRI Initial Comments at 25.
---------------------------------------------------------------------------

b. Commission Determination
    208. Pursuant to section 215(d)(5) of the FPA, we adopt the NOPR 
proposal and direct NERC to develop and submit to the Commission for 
approval new or modified Reliability Standards that require post-
disturbance ramp rates for registered IBRs to be unrestricted and not 
programmed to artificially interfere with the resource returning to a 
pre-disturbance output level in a quick and stable manner after a Bulk-
Power System disturbance event. The proposed Reliability Standards must 
account for the technical differences between registered IBRs and 
synchronous generation resources, such as registered IBRs' faster 
control capability to ramp power output down or up when capacity is 
available.\385\ Further, the Reliability Standards must require 
generator owners to communicate to the relevant planning coordinators, 
transmission planners, reliability coordinators, transmission 
operators, and balancing authorities the actual post-disturbance ramp 
rates and the ramp rates to meet expected dispatch levels (i.e., 
generation-load balance).
---------------------------------------------------------------------------

    \385\ NOPR, 181 FERC ] 61,125 at P 96.
---------------------------------------------------------------------------

    209. We direct NERC to submit to the Commission for approval new or 
modified Reliability Standards that would require registered IBRs to 
ride through any conditions not addressed by the proposed new or 
modified Reliability Standards that address frequency or voltage ride 
through, including phase lock loop loss of synchronism. The proposed 
new or modified Reliability Standards must require registered IBRs to 
ride through momentary loss of synchronism during Bulk-Power System 
disturbances and require registered IBRs to continue to inject current 
into the Bulk-Power System at pre-disturbance levels during a 
disturbance, consistent with the IBR Interconnection Requirements 
Guideline and Canyon 2 Fire Event Report recommendations.\386\ Related 
to ACP/SEIA's comment recommending to revise the directive to require 
generators to maintain synchronism where possible and continue to 
inject current to support system stability, we direct NERC, through its 
standard development process, to consider whether there are conditions 
that may limit generators to maintain synchronism.
---------------------------------------------------------------------------

    \386\ Id. P 97; see also Canyon 2 Fire Event Report at 20 
(recommending that ``[i]nverters should not trip for momentary 
[phase lock loop] loss of synchronism caused by phase jumps, 
distortion, etc., during [Bulk-Power System] grid events (e.g., 
faults). Inverters should continue to inject current into the grid 
and, at a minimum, lock the [phase lock loop] to the last 
synchronized point and continue injecting current to the [Bulk-Power 
System] at that calculated phase until the [phase lock loop] can 
regain synchronism upon fault clearing.'').
---------------------------------------------------------------------------

    210. Regarding NERC's comment informing that NERC is considering 
whether to amend the Project 2020-02 Modifications to PRC-024 
(Generator Ride-through) scope, while NERC did not request any 
particular Commission action, we support such project modification as 
consistent with our above directive that registered IBRs ride through 
any conditions, including phase lock loop loss of synchronism. 
Similarly, we believe that EPRI's suggestion to use comprehensive and 
holistic ride through capability and performance requirements instead 
of a piecemeal approach to addressing performance concerns that may 
exclude other ride through capability and performance requirements 
aligns with our above directive.
    211. Related to SPP's comment to include in the final rule 
consideration of IEEE 2800-2022 to address ramp rate interactions and 
phase lock loop synchronization of registered IBRs, we decline to 
direct NERC to specifically reference IEEE standards in its new or 
modified Reliability Standards for similar reasons as discussed above 
in section IV.E.1. Rather, NERC has the discretion to consider during 
its standards development process whether and how to reference IEEE 
standards in the new or modified Reliability Standards. As discussed in 
section IV.F below, NERC's informational filing should discuss how it 
is considering standard development projects already underway to meet 
the directives in this final action.

F. Informational Filing and Reliability Standard Development Timeline

    212. In the NOPR, the Commission proposed to direct NERC to submit 
a compliance filing within 90 days of the effective date of the final 
rule in this proceeding. The proposed compliance filing would include a 
detailed, comprehensive standards development and implementation plan 
explaining how NERC will prioritize the development and implementation 
of

[[Page 74284]]

new or modified Reliability Standards. The Commission proposed 
requiring NERC to explain in its compliance filing how it is 
prioritizing its IBR Reliability Standard projects to meet the 
directives in the final rule, taking into account the risks posed to 
the reliability of the Bulk-Power System, standard development projects 
already underway, resource constraints, and other factors as 
necessary.\387\
---------------------------------------------------------------------------

    \387\ Id. P 72.
---------------------------------------------------------------------------

    213. The Commission proposed to direct NERC to use a staggered 
approach that would result in NERC submitting new or modified 
Reliability Standards in three stages: (1) new or modified Reliability 
Standards including directives related to registered IBR failures to 
ride through frequency and voltage variations during normally cleared 
Bulk-Power System faults filed with the Commission within 12 months of 
Commission approval of the plan; (2) new or modified Reliability 
Standards addressing the interconnected directives related to 
registered IBR, unregistered IBR, and IBR-DER data sharing; registered 
IBR disturbance monitoring data sharing; registered IBR, unregistered 
IBR, and IBR-DER data and model validation; and registered IBR, 
unregistered IBR, and IBR-DER planning and operational studies filed 
with the Commission within 24 months of Commission approval of the 
plan; and (3) new or modified Reliability Standards including the 
remaining directives for post-disturbance ramp rates and phase lock 
loop synchronization filed with the Commission within 36 months of 
Commission approval of the plan.\388\
---------------------------------------------------------------------------

    \388\ Id. P 73.
---------------------------------------------------------------------------

1. Comments
    214. NERC supports a directive to require a compliance filing 
within 90 days.\389\ NERC generally supports the Commission's proposal 
for a compliance filing, including a standards development plan.\390\ 
Nevertheless, NERC seeks clarification of the Commission's use of 
``implementation plan'' and whether that phrase refers to the timeline 
for developing responsive new or modified Reliability Standards or the 
timeline for entity implementation of the approved new or modified 
Reliability Standards. NERC cautions that if implementation plan means 
``the time for an entity to implement a new or revised Reliability 
Standard,'' then it would be unable to provide meaningful information 
for Reliability Standards still in development because reasonable 
implementation periods are still under consideration through NERC's 
Commission-approved Reliability Standard development process.\391\
---------------------------------------------------------------------------

    \389\ NERC Initial Comments at 23.
    \390\ Id.
    \391\ Id. at 23-24.
---------------------------------------------------------------------------

    215. Indicated Trade Associations suggest directing NERC to include 
in its work plan a comparison to its ongoing IBR-related standards 
projects' scopes and how each relates to the directives in the final 
rule.\392\ Indicated Trade Associations caution against losing the work 
already completed.\393\ Indicated Trade Associations and IRC point to 
existing NERC projects addressing reliability gaps pertaining to IBR 
data sharing that could be leveraged to address the proposed 
directives, including Project 2020-06 (Verifications of Models and Data 
for Generators), Project 2022-02 (Modifications to Reliability 
Standards TPL-001-5.1 and MOD-032-1), and Project 2021-04 
(Modifications to Reliability Standard PRC-002-2).\394\
---------------------------------------------------------------------------

    \392\ Indicated Trade Associations Initial Comments at 2.
    \393\ Id. at 5.
    \394\ Id. at 6; IRC Initial Comments at 3.
---------------------------------------------------------------------------

    216. SCE/PG&E, while broadly supportive of the Commission's goals, 
recommend initiating a pilot program as a first step before progressing 
to directives for new or modified Reliability Standards. SCE/PG&E 
recommend that the pilot program should study: (1) changes by the CAISO 
to address IBRs and consider whether they translate to national 
standards; (2) interconnection tariff revisions under review at the 
California Public Utilities Commission under California Electric Rule 
21; and (3) systems with high-IBR penetrations and what information is 
available to distribution providers, generator owners, generator 
operators, transmission owners, and transmission operators within these 
footprints.\395\ SCE/PG&E assert that NERC could take advantage of 
ongoing state actions to ensure reliable operation and to coordinate 
with the states so there are no conflicting obligations.\396\
---------------------------------------------------------------------------

    \395\ SCE/PG&E Initial Comments at 9-11.
    \396\ Id. at 10.
---------------------------------------------------------------------------

    217. NERC, AEP, Bonneville, CAISO, and Ohio FEA generally support 
the idea of a staggered standard development plan but provide some 
recommendations to adjust the schedule to take advantage of NERC's 
ongoing standard development projects. NERC proposes an alternate 
timeline whereby it would submit proposed new or modified Reliability 
Standards addressing: (1) comprehensive ride through requirements 
(including frequency, voltage, post-disturbance ramp rates, and phase 
lock loop synchronization), post-event performance validation, and 
disturbance monitoring data within 12 months of Commission approval of 
the plan; (2) data sharing issues, other than disturbance monitoring 
data, and data and model validation for registered and unregistered 
IBRs and IBR-DERs in the aggregate within 24 months of Commission 
approval of the plan; and (3) planning and operational studies for 
registered and unregistered IBRs and IBR-DERs in the aggregate within 
36 months of Commission approval of the plan.\397\ NERC explains that 
its alternate timeline would leverage existing and planned activities 
more efficiently and address higher priority risks more expeditiously, 
while allowing sufficient time to develop consensus approaches on other 
issues.\398\
---------------------------------------------------------------------------

    \397\ NERC Initial Comments at 26-30.
    \398\ Id. at 24.
---------------------------------------------------------------------------

    218. AEP and CAISO support the Commission's proposed staggered 
approach but suggest modifying the proposal to include all aspects of 
ride through performance (i.e., phase lock loop synchronization and 
post-disturbance ramp rates) in the first stage.\399\ Further, as NERC 
is working on addressing currently unregistered IBR generator owners 
and operators, AEP recommends addressing the interconnected issues 
related to registered and unregistered IBR and IBR-DER data sharing, 
validation, and studies after the remaining directives in the three-
year time frame.\400\
---------------------------------------------------------------------------

    \399\ AEP Initial Comments at 5; CAISO Initial Comments at 5.
    \400\ AEP Initial Comments at 6.
---------------------------------------------------------------------------

    219. Bonneville believes that the three-year proposed timeline 
should be extended to five years.\401\ Bonneville explains that the 
proposed directives for data sharing, model validation, and studies 
will ``require extensive industry collaboration'' and that a five-year 
timeline will ensure that NERC and industry have adequate time to 
develop the standards, especially as Bonneville notes there will be an 
increase in generation interconnection requests and corresponding need 
for additional model validation.\402\
---------------------------------------------------------------------------

    \401\ Bonneville Initial Comments at 1.
    \402\ Id. at 3.
---------------------------------------------------------------------------

    220. Ohio FEA anticipates that using a staggered standards 
development timeline will provide additional opportunities for 
stakeholders to participate in the development of the new or modified 
Reliability Standards and recommends robust comment

[[Page 74285]]

periods at each stage in the staggered approach.\403\
---------------------------------------------------------------------------

    \403\ Ohio FEA Initial Comments at 7.
---------------------------------------------------------------------------

    221. ACP/SEIA caution that, although supportive of ride through 
requirements, one year to develop such standards is a short time when 
compared with how long it typically takes to develop Reliability 
Standards and may be infeasible if NERC does not use its existing 
standards development projects to comply with the rule.\404\
---------------------------------------------------------------------------

    \404\ ACP/SEIA Initial Comments at 4.
---------------------------------------------------------------------------

2. Commission Determination
    222. Pursuant to Sec.  39.2(d) of the Commission's 
regulations,\405\ we modify the NOPR proposal and direct NERC to submit 
an informational filing within 90 days of the issuance of the final 
rule in this proceeding. Further, pursuant to section 215(d)(5)(g) of 
the FPA, we direct NERC to submit new or modified Reliability Standards 
addressing the reliability concerns outlined herein by certain 
deadlines, detailed further below.
---------------------------------------------------------------------------

    \405\ 18 CFR 39.2(d).
---------------------------------------------------------------------------

    223. NERC's informational filing should include a detailed, 
comprehensive standards development plan and explanation of how NERC 
will prioritize the development of new or modified Reliability 
Standards directed in this rule. We agree with NERC and Indicated Trade 
Associations, among others, that there are existing projects that can 
be leveraged to address our directives in a timely manner.\406\ 
Therefore, NERC should take into account the risk posed to the 
reliability of the Bulk-Power System, standard development projects 
already underway, resource constraints, its ongoing registration of 
Bulk-Power System-connected IBR generator owners and operators, and 
other factors as necessary.\407\ As we recognized in the NOPR, data 
models and validation build and rely upon the data sharing directives. 
Similarly, the planning and operational study directives require the 
use of validated models and data sharing.\408\
---------------------------------------------------------------------------

    \406\ See, e.g., NERC Initial Comments at 22; Indicated Trades 
Associations Initial Comments at 8 (discussing NERC Project 2020-02 
Modifications to PRC-024 (Generator Ride-through) and its updated 
scope to address IBR ride through performance).
    \407\ See IBR Registration Order, 181 FERC ] 61,124.
    \408\ NOPR, 181 FERC ] 61,125 at P 74.
---------------------------------------------------------------------------

    224. In its comments, NERC provides an alternate timeline it 
explains would leverage its existing and planned activities more 
efficiently. It references initiatives already underway and highlights 
several ongoing standards development projects that could be adjusted 
to address the directives in this final action.\409\ As NERC explains 
in its comments, a standards development plan provides visibility to 
both the Commission and stakeholders on how NERC will address the 
important reliability issues identified in this final action. In the 
interest of time, however, and as NERC appears to have already extended 
considerable effort in thinking through how it would address IBR-
related gaps through its Reliability Standard projects, we do not find 
it necessary to approve NERC's final work plan.
---------------------------------------------------------------------------

    \409\ NERC Initial Comments at 21-22.
---------------------------------------------------------------------------

    225. As requested by NERC, we clarify that the Commission's 
reference to ``implementation'' in the NOPR means the date on which the 
new or modified Reliability Standards would become mandatory and 
enforceable for relevant registered entities. But we find persuasive 
NERC's assertion that that the implementation plan is better developed 
standard-by-standard through NERC's Commission approved Reliability 
Standard development process. Therefore, we decline to direct NERC to 
include in its informational filing the dates by which all of the new 
or modified Reliability Standards would be mandatory and effective.
    226. Although we are not directing NERC to include implementation 
dates in its informational filing and are leaving determination of the 
proposed 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 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 consider the 
justness and reasonableness of each new or modified Reliability 
Standard's implementation plan when it is submitted for Commission 
approval.\410\ Further, we believe that there is a need to have all of 
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 that date.
---------------------------------------------------------------------------

    \410\ 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.'').
---------------------------------------------------------------------------

    227. We decline to direct NERC to implement a pilot program to 
better analyze the impact of IBRs on the Bulk-Power System as requested 
by SCE/PG&E. While there may be merit in conducting a pilot program for 
systems with high-IBR penetrations to better understand what 
information is available to distribution providers, generator owners, 
generator operators, transmission owners, and transmission operators 
within these footprints, we leave to NERC's discretion the value of 
such a study; and in any case such a pilot program must not impact the 
prioritization or timely completion of the directed Reliability 
Standards.
    228. We agree with NERC, CAISO, and AEP that the stages should be 
modified from the NOPR proposal to group the ride through directives 
and the development of new or modified Reliability Standards for data 
sharing and model validation to inform the standard development for 
planning and operational studies.
    229. Therefore, as we are persuaded by commenters' suggestions 
regarding the proposed staggered groupings for new or modified 
Reliability Standards, 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. NERC's standards 
development plan submitted as a part of its informational filing 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, post-disturbance ramp rates, phase lock loop 
synchronization, and other known causes of IBR tripping or momentary 
cessation (section IV.E.). 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 (section IV.B.2.). Second, by November 4, 2025,

[[Page 74286]]

NERC must submit new or modified Reliability Standards addressing the 
interrelated directives concerning: (1) data sharing for registered 
IBRs (section IV.B.1), unregistered IBRs (section IV.B.3.), and IBR-
DERs in the aggregate (section IV.B.3.); and (2) data and model 
validation for registered IBRs, unregistered IBRs, and IBR-DERs in the 
aggregate (section IV.C.). 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 (section IV.D.). We continue to believe this 
staggered approach to standard development 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.
    230. NERC may expedite its standards development plan and submit 
new or modified Reliability Standards prior to the deadlines. We 
decline to extend the three-year staggered approach to a five-year 
staggered approach as requested by Bonneville due to the pressing 
nature of the Commission's concerns discussed above, such as IBR 
momentary cessation occurring in the aggregate today that can lead to 
instability, system-wide uncontrolled separation, and voltage collapse.

V. Information Collection Statement

    231. The information collection requirements contained in this 
order are subject to review by the Office of Management and Budget 
(OMB) under section 3507(d) of the Paperwork Reduction Act of 
1995.\411\ OMB's regulations require approval of certain information 
collection requirements imposed by agency rules.\412\ Upon approval of 
a collection of information, OMB will assign an OMB control number and 
expiration date. Respondents subject to the filing requirements of this 
rule will not be penalized for failing to respond to this collection of 
information unless the collection of information displays a valid OMB 
control number. Comments are solicited on the Commission's need for the 
information proposed to be reported, whether the information will have 
practical utility, ways to enhance the quality, utility, and clarity of 
the information to be collected, and any suggested methods for 
minimizing the respondent's burden, including the use of automated 
information techniques.
---------------------------------------------------------------------------

    \411\ 44 U.S.C. 3507(d).
    \412\ 5 CFR 1320.11.
---------------------------------------------------------------------------

    232. The directives to NERC to submit new or modified Reliability 
Standards that address specific matters pertaining to the impacts of 
IBRs on the reliable operation of the Bulk-Power System are covered by, 
and already included in, the existing OMB-approved information 
collection FERC-725 (Certification of Electric Reliability 
Organization; Procedures for Electric Reliability Standards; OMB 
Control No. 1902-0225), under Reliability Standards Development.\413\ 
In this final action, 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.
---------------------------------------------------------------------------

    \413\ Reliability Standards Development as described in FERC-725 
covers standards development initiated by NERC, the Regional 
Entities, and industry, as well as Reliability Standards the 
Commission may direct NERC to develop or modify. The information 
collection associated with this final action ordinarily would be a 
non-material addition to FERC-725. However, an information 
collection request unrelated to this final action is pending review 
under FERC-725 at the Office of Management and Budget. To submit 
this final action timely to OMB, we will submit this to OMB as a 
temporary placeholder under FERC-725(1A), OMB Control No. 1902-0289.
---------------------------------------------------------------------------

    233. Necessity of Information. 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.

VI. Environmental Analysis

    234. The Commission is required to prepare an Environmental 
Assessment or an Environmental Impact Statement for any action that may 
have a significant adverse effect on the human environment.\414\ The 
Commission has categorically excluded certain actions from this 
requirement as not having a significant effect on the human 
environment. Included in the exclusion are rules that are clarifying, 
corrective, or procedural or that do not substantially change the 
effect of the regulations being amended.\415\ The actions directed 
herein fall within this categorical exclusion in the Commission's 
regulations.
---------------------------------------------------------------------------

    \414\ Reguls. Implementing the Nat'l Env't Pol'y Act, Order No. 
486, 52 FR 47897 (Dec. 17, 1987), FERC Stats. & Regs. ] 30,783 
(1987) (cross-referenced at 41 FERC ] 61,284).
    \415\ 18 CFR 380.4(a)(2)(ii).
---------------------------------------------------------------------------

VII. Regulatory Flexibility Act

    235. The Regulatory Flexibility Act of 1980 (RFA) \416\ generally 
requires a description and analysis of final rules that will have 
significant economic impact on a substantial number of small entities. 
This final action directs NERC, the Commission-certified ERO, to 
develop new or modified Reliability Standards for IBRs on the Bulk-
Power System. Therefore, this final action will not have a significant 
or substantial impact on entities other than NERC.\417\ Consequently, 
the Commission certifies that this final action will not have a 
significant economic impact on a substantial number of small entities.
---------------------------------------------------------------------------

    \416\ 5 U.S.C. 601-612.
    \417\ See, e.g., Transmission Sys. Plan. Performance 
Requirements for Extreme Weather, Order No. 896, 88 FR 41262 (June 
23, 2023), 183 FERC ] 61,191, at P 198 (2023).
---------------------------------------------------------------------------

    236. Any new or modified Reliability Standards proposed by NERC in 
compliance with this rulemaking will be considered by the Commission in 
future proceedings. As part of any future proceedings, the Commission 
will make determinations pertaining to the RFA based on the content of 
the Reliability Standards proposed by NERC.

VIII. Document Availability

    237. In addition to publishing the full text of this document in 
the Federal Register, the Commission provides all interested persons an 
opportunity to view and/or print the contents of this document via the 
internet through the Commission's Home Page (http://www.ferc.gov).
    238. From FERC's Home Page on the internet, this information is 
available on eLibrary. The full text of this document is available on 
eLibrary in PDF and Microsoft Word format for viewing, printing, and/or 
downloading. To access this document in eLibrary, type the docket 
number excluding the last three digits of this document in the docket 
number field.
    239. User assistance is available for eLibrary and the FERC's 
website during normal business hours from FERC Online Support at (202) 
502-6652 (toll free at 1-866-208-3676) or email at 
<a href="/cdn-cgi/l/email-protection#ff999a8d9c90919396919a8c8a8f8f908d8bbf999a8d9cd1989089"><span class="__cf_email__" data-cfemail="c7a1a2b5a4a8a9abaea9a2b4b2b7b7a8b5b387a1a2b5a4e9a0a8b1">[email protected]</span></a>, or the Public Reference Room at (202) 502-
8371, TTY (202) 502-8659. Email the Public Reference Room at 
<a href="/cdn-cgi/l/email-protection#9dede8fff1f4feb3eff8fbf8eff8f3fef8eff2f2f0ddfbf8effeb3faf2eb"><span class="__cf_email__" data-cfemail="4f3f3a2d23262c613d2a292a3d2a212c2a3d2020220f292a3d2c61282039">[email protected]</span></a>.

[[Page 74287]]

IX. Effective Date and Congressional Notification

    240. This final action is effective December 29, 2023. The 
Commission has determined, with the concurrence of the Administrator of 
the Office of Information and Regulatory Affairs of OMB, that this rule 
is not a ``major rule'' as defined in section 351 of the Small Business 
Regulatory Enforcement Fairness Act of 1996.
    By the Commission. Commissioner Danly is concurring with a separate 
statement attached.

    Issued October 19, 2023
Kimberly D. Bose,
Secretary.

Appendix A: Commenter Names

------------------------------------------------------------------------
             Acronyms                          Commenter name
------------------------------------------------------------------------
AEU...............................  Advanced Energy United.
ACP/SEIA..........................  American Clean Power Association and
                                     Solar Energy Industries
                                     Association.
AEP...............................  American Electric Power Service
                                     Corporation.
APS...............................  Arizona Public Service Company.
Bonneville........................  Bonneville Power Administration.
CAISO.............................  California Independent System
                                     Operator Corporation.
EPRI..............................  Electric Power Research Institute.
Indicated Trade Associations......  Edison Electric Institute, American
                                     Public Power Association, Large
                                     Public Power Council, National
                                     Rural Electric Cooperative
                                     Association, and Transmission
                                     Access Policy Study Group.
infiniRel.........................  infiniRel Corporation.
ISO-NE............................  ISO New England Inc.
IRC...............................  ISO/RTO Council.
NYSRC.............................  New York State Reliability Council.
LADWP.............................  Los Angeles Department of Water and
                                     Power.
Ohio FEA..........................  Public Utilities Commission of
                                     Ohio's Office of the Federal Energy
                                     Advocate.
Mr. Plankey.......................  Sean P. Plankey.
SCE/PG&E..........................  Southern California Edison Company
                                     and Pacific Gas and Electric
                                     Company.
SPP...............................  Southwest Power Pool, Inc.
UNIFI.............................  Universal Interoperability for Grid-
                                     forming Inverters Consortium.
------------------------------------------------------------------------

Appendix B: NERC IBR Resources Cited in the Final Action

NERC Guidelines

    NERC Guidelines referenced in this NOPR are available here: 
https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx.
    NERC, Reliability Guideline: Modeling Distributed Energy 
Resources in Dynamic Load Models (Dec. 2016), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_-_Modeling_DER_in_Dynamic_Load_Models_-_FINAL.pdf (retired).
    NERC, Reliability Guideline: Distributed Energy Resources 
Modeling, (Sept. 2017), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_-_DER_Modeling_Parameters_-_2017-08-18_-_FINAL.pdf (retired).
    NERC, Reliability Guideline: BPS-Connected Inverter-Based 
Resource Performance (Sept. 2018), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf (IBR Performance 
Guideline).
    NERC, Reliability Guideline: Parameterization of the DER_A Model 
(Sept. 2019), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf (2019 DER_A Model 
Guideline) (retired).
    NERC, Reliability Guideline: DER Data Collection for Modeling in 
Transmission Planning Studies (Sept. 2020), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf (IBR-DER 
Data Collection Guideline).
    NERC, Reliability Guideline: Model Verification of Aggregate DER 
Models used in Planning Studies (Mar. 2021), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline%20_DER_Model_Verification_of_Aggregate_DER_Models_used_in_Planning_Studies.pdf (Aggregate DER Model Verification 
Guideline).
    NERC, Reliability Guideline: Parameterization of the DER_A Model 
for Aggregate DER (Feb. 2023), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_ModelingMerge_Responses_clean.pdf (2023 DER_A 
Model Guideline).
    NERC, Reliability Guideline: Electromagnetic Transient Modeling 
for BPS-Connected Inverter-Based Resources--Recommended Model 
Requirements and Verification Practices (Mar. 2023), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline-EMT_Modeling_and_Simulations.pdf.

NERC White Papers

    IRPTF white papers referenced in this NOPR are available here: 
https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx.
    NERC, A Concept Paper on Essential Reliability Services that 
Characterizes Bulk Power System Reliability (Oct. 2014), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf (Essential Reliability Services Concept 
Paper).
    NERC, Resource Loss Protection Criteria Assessment (Feb. 2018), 
https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf.
    NERC, Fast Frequency Response Concepts and Bulk Power System 
Reliability Needs (Mar. 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf (Fast Frequency Response White Paper).

NERC Reports

    NERC, 2013 Long-Term Reliability Assessment (Dec. 2013), https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf (2013 LTRA Report).
    NERC, Distributed Energy Resources: Connection Modeling and 
Reliability Considerations (Feb. 2017), https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf (NERC DER Report).
    NERC, 2020 Long Term Reliability Assessment Report (Dec. 2020), 
https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf (2020 LTRA Report).
    NERC, 2021 Long Term Reliability Assessment Report (Dec. 2021), 
https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf (2021 LTRA Report).

NERC Technical Reports

    NERC technical reports referenced in this NOPR are available 
here: https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx.
    NERC, Technical Report, BPS-Connected Inverter-Based Resource 
Modeling and Studies (May 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_IBR_Modeling_and_Studies_Report.pdf (Modeling and Studies 
Report).

[[Page 74288]]

    NERC and WECC, WECC Base Case Review: Inverter-Based Resources 
(Aug. 2020), https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf (Western Interconnection Base Case 
IBR Review).

NERC Major Event Reports

    NERC event reports referenced in this NOPR are available here: 
https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx.
    NERC, 1,200 MW Fault Induced Solar Photovoltaic Resource 
Interruption Disturbance Report (June 2017), https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf (Blue Cut Fire Event Report) (covering the Blue Cut Fire event 
(August 16, 2016)).
    NERC and WECC, 900 MW Fault Induced Solar Photovoltaic Resource 
Interruption Disturbance Report (Feb. 2018), https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf (Canyon 2 Fire Event Report) (covering the Canyon 2 
Fire event (October 9, 2017)).
    NERC and WECC, April and May 2018 Fault Induced Solar 
Photovoltaic Resource Interruption Disturbances Report (Jan. 2019), 
https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf (Angeles Forest and 
Palmdale Roost Events Report) (covering the Angeles Forest (April 
20, 2018) and Palmdale Roost (May 11, 2018) events).
    NERC and WECC, San Fernando Disturbance, (Nov. 2020), https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf 
(San Fernando Disturbance Report) (covering the San Fernando event 
(July 7, 2020)).
    NERC and Texas RE, Odessa Disturbance (Sept. 2021) https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf 
(Odessa 2021 Disturbance Report) (covering events in Odessa, Texas 
on May 9, 2021 and June 26, 2021).
    NERC and WECC, Multiple Solar PV Disturbances in CAISO (Apr. 
2022), https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf (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)).
    NERC and Texas RE, March 2022 Panhandle Wind Disturbance Report 
(Aug. 2022), https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf (Panhandle Disturbance Report) 
(covering the Texas Panhandle event (March 22, 2022)).
    NERC and Texas RE, 2022 Odessa Disturbance (Dec. 2022), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2022_Odessa_Disturbance_Report%20(1).pdf (Odessa 2022 
Disturbance Report) (covering events in Odessa, Texas on June 4, 
2022).
    NERC and WECC, 2023 Southwest Utah Disturbance (Aug. 2023), 
https://www.nerc.com/comm/RSTC_Reliability_Guidelines/NERC_2023_Southwest_UT_Disturbance_Report.pdf (Southwest Utah 
Disturbance Report) (covering events in Southwestern Utah on April 
10, 2023).

NERC Alerts

    NERC Alerts referenced in this NOPR are available here: https://www.nerc.com/pa/rrm/bpsa/Pages/Alerts.aspx.
    NERC, Industry Recommendation: Loss of Solar Resources during 
Transmission Disturbances due to Inverter Settings--II (May 2018), 
https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf (Loss of Solar Resources Alert II).
    NERC, Industry Recommendation: Inverter-Based Resource 
Performance Issues, (Mar. 2023), 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 (March 2023 
Alert).

Other NERC Resources

    NERC Libraries of Standardized Powerflow Parameters and 
Standardized Dynamics Models version 1 (Oct. 2015), https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf (NERC 
Standardized Powerflow Parameters and Dynamics Models).
    NERC, Events Analysis Modeling Notification Recommended 
Practices for Modeling Momentary Cessation Initial Distribution 
(Feb. 2018), https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf.
    NERC, Case Quality Metrics Annual Interconnection-wide Model 
Assessment, (Oct. 2021), https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf.
    NERC, Inverter-Based Resource Strategy: Ensuring Reliability of 
the Bulk Power System with Increased Levels of BPS-Connected IBRs 
(Sept. 2022), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf (NERC IBR Strategy).

United States of America

Federal Energy Regulatory Commission

Reliability Standards to Address Inverter-Based Resources
Docket No. RM22-12-000

    DANLY, Commissioner, concurring:
    1. I concur in today's order \1\ in which we direct NERC to develop 
new or modified mandatory and enforceable Reliability Standards prior 
to 2030 in order to address a set of reliability risks we have known 
about, and been actively discussing, since at least 2016 and about 
which I have long warned. Is today's order important and necessary? 
Yes. Is it timely? No. Six of the thirteen documented events occurred 
in 2021.\2\ The Commission and NERC could have, and should have, acted 
sooner, particularly since 2030 marks the time at which inverter-based 
resources (IBRs) ``are projected to account for a significant share of 
the electric energy generated in the United States.'' \3\
---------------------------------------------------------------------------

    \1\ Reliability Standards to Address Inverter-Based Resources, 
185 FERC ] 61,042 (2023).
    \2\ Id. P 26 & n.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).''). On June 4, 2022, an IBR-related disturbance near 
Odessa, Texas (the third in this location) occurred. Id. P 27.
    \3\ Id. P 58 (footnote omitted).
---------------------------------------------------------------------------

    2. The reliability risks at issue arise from the rapid, widespread 
(one might say reckless) addition of IBRs (e.g., wind and solar) to the 
Bulk-Power System (BPS).\4\ According to NERC, ``[t]he rapid 
interconnection of [BPS]-connected [IBRs] is the most significant 
driver of grid transformation and poses a high risk to BPS 
reliability.'' \5\ As NERC has explained, ``[e]ach event analyzed has 
identified new performance issues, such as momentary cessation, 
unwarranted inverter or plant-level tripping issues, controller 
interactions and instabilities, and other critical performance risks 
that must be mitigated.'' \6\ ``Simulations conducted by the NERC 
Resource Subcommittee demonstrate that the risks to the [BPS] 
reliability posted by momentary cessation are greater than any of the 
actual IBR disturbances that NERC has documented since 2016 . . . These 
simulation results indicate that IBR momentary cessation occurring in 
the aggregate can lead to instability, system-wide uncontrolled 
separation, and voltage collapse.'' \7\
---------------------------------------------------------------------------

    \4\ Id. P 2.
    \5\ NERC, Inverter-Based Resource Strategy: Ensuring Reliability 
of the Bulk Power System with Increased Levels of BPS-Connected 
IBRs, at 1 (June 2022) (footnote omitted), https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf.
    \6\ Id. at 4.
    \7\ Reliability Standards to Address Inverter-Based Resources, 
185 FERC ] 61,042 at P 14 (citations omitted).
---------------------------------------------------------------------------

    3. NERC has also observed ``[m]ultiple recent disturbances that 
involve the

[[Page 74289]]

widespread reduction of solar photovoltaic (PV) resources have occurred 
in California, Utah, and Texas.'' \8\ The ``first major events 
involving [battery energy storage system facilities'' occurred just 
last year in March and April, 2022.\9\ The reliable operation of the 
Bulk-Power System remains imperiled until these issues are addressed. 
Time is of the essence.
---------------------------------------------------------------------------

    \8\ 2022 California Battery Energy Storage Sys. Disturbances, 
California Events: March 9 and April 6, 2022, Joint NERC and WECC 
Staff Report, at iv (Sept. 2023), https://www.nerc.com/comm/RSTC/Documents/NERC_BESS_Disturbance_Report_2023.pdf.
    \9\ Id.
---------------------------------------------------------------------------

    4. Our oversight role requires us to remain vigilant in ensuring 
that NERC Reliability Standards are timely, efficient, and effective. 
Up to nearly fourteen years to establish mandatory and enforceable NERC 
Reliability Standards to address a known, and potentially catastrophic, 
risk to the reliability of the BPS is simply too long a time to wait. 
And we will have to wait yet longer to learn whether the standards we 
do ultimately implement end up proving effective. Who knows what will 
happen in the meantime.
    5. Better late than never, I suppose.
    For these reasons, I respectfully concur.

-----------------------------------------------------------------------
James P. Danly,
Commissioner.

[FR Doc. 2023-23581 Filed 10-27-23; 8:45 am]
BILLING CODE 6717-01-P


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