ER26-3650-000 · 2026-08-28 · Midcontinent Independent System Operator, Inc.

MISO proposes interconnection reliability requirements for large loads

Midcontinent Independent 
System Operator, Inc. 
317.249-5400 
www.misoenergy.org 
720 City Center Drive 
Carmel, Indiana 46032 
2985 Ames Crossing Road 
Eagan, Minnesota 55121 
1700 Centerview Drive 
Little Rock, AR 72211 
 
Michael Kessler 
Managing Assistant General Counsel 
Direct Dial:  317-753-9434 
Email:  mkessler@misoenergy.org 
August 28, 2026 
VIA ELECTRONIC FILING 
The Honorable Debbie-Anne Reese  
Secretary 
Federal Energy Regulatory Commission 
888 First Street, NE 
Washington, DC  20426 
Re: 
Midcontinent Independent System Operator, Inc.’s  
Interconnection Reliability Requirements for Large Loads 
Docket No. ER26-___-000 
 
Dear Secretary Reese: 
The Midcontinent Independent System Operator, Inc. (“MISO”), through this filing,1 
submits proposed revisions to its Open Access Transmission, Energy and Operating Reserve 
Markets Tariff (“Tariff”),2 to establish certain Interconnection Reliability Requirements for Large 
Loads (the “IRR Proposal”).3  The IRR Proposal is responsive to several of the concerns raised by 
the Commission in the Order Instituting Proceeding Under Section 206 of the Federal Power Act4 
in Docket No. EL26-70-000 by proposing visibility, ramp rate, and disturbance ride-through 
requirements applicable to Large Loads, along with transition provisions to minimize disruption 
to commercial arrangements.  Other issues raised in the Show Cause Order, including the 
development of additional transmission products for Large Loads and associated study processes, 
cost shifting, protections against cost shifts and the treatment of generation service to electrically 
proximate to Large Loads, will be addressed through MISO’s forthcoming Large Load proposals. 
 
1  
This filing is made pursuant to section 205 of the Federal Power Act (“FPA”), 16 U.S.C. § 824d, and Part 35 of 
the regulations of the Federal Energy Regulatory Commission (“FERC” or “Commission”), 18 C.F.R. § 35.1, et 
seq. 
2  
Unless otherwise indicated by the text or context of this transmittal letter, all terms used herein have the definitions 
set forth in Module A of the Tariff. 
3  
As discussed below, MISO proposes to defined Large Load as Load with Demand of 50 MW or more associated 
with any facility or aggregation of facilities located at a single substation behind one or more Point(s) of 
Withdrawal from the Transmission System that is owned, operated, or controlled by: (a) a single entity or (b) a 
group of entities that will coordinate with respect to the profile of the Load.  Large Load does not include Load 
used exclusively for charging an Electric Storage Resource. 
4  
Midcontinent Independent System Operator, Inc., Order Instituting Proceeding Under Section 206 of the Federal 
Power Act, 195 FERC ¶ 61,212 (2026) (“Show Cause Order” or “SCO”).

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 2 
 
 
MISO requests that the Tariff revisions submitted herewith be made effective December 4, 
2026, which is not less than sixty (60) days nor more than one-hundred and twenty (120) days 
from the date of this filing.  As discussed below and in the supporting testimony of Ms. BeiBei Li, 
action is needed in the near term to enhance the available tools to address the reliability impacts 
associated with the impending interconnection of Load, including the anticipated interconnection 
of significant Large Loads. 
I. 
EXECUTIVE SUMMARY 
The MISO region is experiencing a significant increase in both the scale and pace of Large 
Load development.  MISO’s 2026 Long-Term Load Forecast5 indicates that the region is 
experiencing load growth at levels not seen in decades, driven in large part by unprecedented large 
load activity and accelerating project announcements.  Data centers and advanced manufacturing 
are among the primary drivers of this growth, with some projects seeking to develop on timelines 
significantly shorter than those traditionally associated with generation and transmission 
infrastructure.  This combination of increased volume and accelerated development is changing 
the manner in which MISO must plan for and reliably integrate new load.   
 
As this growth has emerged, MISO, its member states, and stakeholders have been 
developing multiple initiatives to address evolving system conditions and to support timely, cost-
effective and reliable interconnection of Large Loads.  For example, MISO’s Expedited Project 
Review (EPR) Process and Expedited Resource Addition Studies (ERAS) complement MISO’s 
determination of needed additional transmission infrastructure, which are being planned and 
implemented through the Joint Targeted Interconnection Queue (JTIQ) and Long Range 
Transmission Plan (LRTP) processes.  An additional and critical proposal, the Zero Injection 
Interconnection Agreement (ZGIA), is currently pending action at the Commission in Docket No. 
ER26-3552.  
 
The issuance of the Commission’s Show Cause Order has reinforced the value of MISO’s 
prior efforts with stakeholders through the stakeholder process, including most recently the Large 
Load Working Group, to develop critical solutions to help support the cost-effective, reliable and 
efficient integration of Large Loads.  MISO continues working diligently with stakeholders on 
several additional initiatives in response to the Show Cause Order and is committed to bringing 
those solutions to the Commission in a timely manner.  
 
MISO appreciates the critical need to reliably integrate Large Loads.  Recent whitepapers 
and alerts published by the North American Electric Reliability Corporation (“NERC”) Large 
Loads Task Force and Large Loads Working Group identify emerging Large Loads as an increasing 
reliability consideration for the Bulk Electric System.  NERC guidance highlights that traditional 
planning and operational assumptions developed for conventional load may not fully capture the 
 
5  
See MISO’s 2026 Long-Term Load Forecasting (LTLF) Results Summary (April 13, 2026), available 
at: https://cdn.misoenergy.org/20260413%20LTLF%20Workshop%202026%20Long%20Term%20Load%20Fo
recast%20Summary_UPDATED750524.pdf

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 3 
 
 
behavior or reliability impacts of emerging large loads, particularly as load facilities grow, can 
change demand rapidly, and rely more heavily on power-electronic equipment.  
 
While NERC processes are underway to develop industry wide guidelines, the MISO 
region cannot wait to put in place needed interconnection reliability requirements to reliably 
integrate these near-term Large Loads.  Developing standards within the MISO region in advance 
of the NERC Standards process is not new.  MISO has similarly acted in the past to establish 
requirements for the interconnection of inverter-based resources in advance of the development of 
NERC Standards relating to such resources.  As Large Load growth accelerates across the MISO 
region these additional reliability considerations and processes are necessary to support 
transmission planning, operational preparedness, disturbance performance, and system stability, 
particularly given the unique characteristics of these facilities.  
 
To support the integration of these new large loads into the MISO system, the IRR Proposal 
establishes a reliability-based framework for Large Loads that complements existing MISO 
planning, interconnection, and operational processes.  The framework is designed to improve 
visibility into Large Load characteristics and behavior, support reliable planning and operational 
decision-making, and establish scalable and technically justified expectations proportional to 
demonstrated reliability risk.  The proposed framework focuses on four categories of reliability 
requirements that will be applicable to Large Loads.  The proposed reliability requirements will 
apply to MISO Transmission Customers providing Transmission Service the Large Load since the 
Transmission Customer is the entity that has a direct relationship with MISO.  The four categories 
of reliability requirements are as follows:  
 
1. 
Visibility Requirements – Data, Modeling, Telemetry, and Forecasting 
Requirements: These requirements establish expectations for facility information, 
electrical models, real-time telemetry, monitoring, short-term and forecasting, and 
other operational visibility requirements necessary to support planning studies, 
operational assessments, and accurate representation of Large Loads behavior and 
system impacts.   
2  
Phasor Measurement Unit (PMU) Requirements: In addition to the broader 
visibility requirements above, the PMU requirements establish enhanced 
monitoring expectations for Computation Loads through high-resolution, time-
synchronized measurements.  PMU data provides MISO with greater visibility into 
facility behavior during system disturbances and rapid operating changes, 
supporting model validation, performance verification, disturbance analysis, and 
identification of potential dynamic interactions with the Transmission System. 
3. 
Ramp Requirements: These requirements 
address 
the rate at 
which 
Computational Loads may increase or decrease consumption during stable-state 
transitions.  Managing rapid changes in demand helps reduce real-time supply-
demand imbalances, sudden change in transmission power flows, and associated 
operational impacts, while supporting more reliable system operation.  Ramp-rate

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 4 
 
 
limits do not apply during fault or disturbance conditions when necessary for 
equipment protection or to satisfy ride-through performance requirements. 
4. 
Ride-Through Requirements: These provisions establish minimum disturbance 
performance requirements applicable to Computational Load during voltage and 
frequency disturbances to reduce the risk of unnecessary disconnection or 
customer-initiated rapid reductions in Demands during credible system events.   
MISO recognizes that the Commission also included the need to develop a study process 
that addresses the unique operational and reliability challenges that providing transmission service 
to Eligible Customers on behalf of large loads presents to the transmission system in its discussion 
of ongoing operational requirements in the Show Cause Order.6  MISO currently conducts such 
studies as part of its stability assessment in the MTEP and EPR processes. The IRR Proposal 
addresses requirements applicable to Large Load facilities themselves.  MISO intends to address 
enhancements to stability assessment study processes in a future Federal Power Act section 205 
filing.  Those future study processes will focus on identifying system-level reliability impacts 
associated with load additions and determining whether transmission or other system-level 
solutions are necessary, as part of a broader set of load addition and transmission service study 
requirements. 
   
MISO appreciates the guidance provided by the Commission through the Show Cause 
Orders as well as its allowance for regional flexibility to develop tailored solutions that meet the 
underlying regional needs and that can support the underlying regional processes.  The challenges 
and opportunities for large load integration differ across regions.  MISO’s expedited stakeholder 
process, in coordination with the MISO Transmission Owners and States, continues through the 
Large Load Working Group.   
 
The previously submitted ZGIA filing and the instant IRR Proposal are the initial steps in 
a broader set of solutions to address the concerns expressed by the Commission in the Show Cause 
Order and to meet the evolving needs of the MISO region.  In addition to the ZGIA and this IRR 
Proposal, MISO continues to develop a series of additional proposals that it plans to the 
Commission in advance of the November 16, 2026, deadline established based on the 
Commission’s abeyance of the Show Cause Order.  First, MISO is refining its Load Addition and 
Resource Study (“LARS”) process to facilitate the parallel study of load and generation that will 
address service to proximate load and support critical speed to power needs.  In addition, MISO is 
working to finalize its Firm Service Step Up proposal, which will provide a practical path to 
provide firm service increases over time as available.  In addition, MISO will work with its 
Transmission Owners and the States to develop and submit the additional proposals to: 1) provide 
additional transmission service products to facilitate Large Load integration; 2) enhance the Large 
Load application and study processes; and, 3) develop additional provisions to address potential 
cost-shifts associated with Large Load additions. 
 
 
6  
Show Cause Order at P 53.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 5 
 
 
II. 
BACKGROUND 
A. 
Large Load Challenges  
 
The United States is in the midst of an unprecedented energy transition.  Large Load 
customers, including artificial intelligence (“AI”) data centers and next-generation manufacturing 
technologies, are driving a surge in interconnection requests. 7  As NERC has observed, the largest 
contributor to this accelerated demand growth is data center additions, with 18 GW of data center 
loads projected by 2035.8  The MISO region is no exception to this energy transition.  Energy-
intensive loads such as data centers, manufacturing expansion, and electrification are adding 
sustained, concentrated load at levels not seen in decades.9  While electricity demand growth has 
been relatively flat with an annual average of just 0.5% between 2009 and 2024, MISO is 
projecting a substantial increase of 1% to 2% per year through 2044, with even higher growth rates 
in the near term.10   
 
This growth has understandably drawn the focus of Relevant Electric Retail Rate 
Authorities (“RERRA”), stakeholders and federal policymakers.  On January 23, 2025, President 
Trump issued an Executive Order stating, “[i]t is the policy of the United States to sustain and 
enhance America’s global AI dominance in order to promote human flourishing, economic 
competitiveness, and national security.”11  On July 23, 2025, an Executive Order titled 
“Accelerating Federal Permitting of Data Center Infrastructure,” the Trump Administration 
announced its intention to pursue bold, large-scale industrial plans to incentivize critical 
manufacturing and data center development:  
 
We will pursue bold, large-scale industrial plans to vault the United 
States further into the lead on critical manufacturing processes and 
technologies that are essential to national security, economic 
prosperity, and scientific leadership.  These plans include artificial 
intelligence (AI) data centers and infrastructure that powers them, 
including high-voltage transmission lines and other equipment.  It 
will be a priority of my Administration to facilitate the rapid and 
 
7  
Long-Term Reliability Assessment, NERC, at 15, 25 (Jan. 2026), available at 
https://www.nerc.com/globalassets/our-work/assessments/nerc_ltra_2025.pdf.   
8  
Long-Term Reliability Assessment, NERC, at 15 (Jan. 2026), available at 
https://www.nerc.com/globalassets/our-work/assessments/nerc_ltra_2025.pdf.   
9  
2026 Reliability Imperative Report, MISO, at. 4 (Feb. 2026), available at 
https://cdn.misoenergy.org/2026%20Reliability%20Imperative%20Report744320.pdf.  
10  2026 Reliability Imperative Report, MISO, at 4 (Feb. 2026), available at 
https://cdn.misoenergy.org/2026%20Reliability%20Imperative%20Report744320.pdf.  
11  Executive Order 14179 of January 23, 2025, “Removing Barriers to American Leadership in Artificial 
Intelligence,” Federal Register 90 (20) 8741, www.govinfo.gov/content/pkg/FR-2025-01-31/pdf/2025-
02172.pdf.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 6 
 
 
efficient buildout of this infrastructure by easing Federal regulatory 
burdens.12 
 
On October 23, 2025, the Secretary of Energy directed the Commission to consider an 
Advance Notice of Proposed Rulemaking (“ANOPR”) focused on the timely and orderly 
interconnection of Large Loads to the interstate transmission system.13  The Secretary’s 
correspondence to the Commission in support of the ANOPR emphasized the importance of the 
timely, orderly, and non-discriminatory integration of Large Loads:   
 
To usher in a new era of American prosperity, we must ensure all 
Americans and domestic industries have access to affordable, 
reliable, and secure electricity.  To do this, Large Loads, including 
AI data centers, served by public utilities must be able to connect to 
the transmission system in a timely, orderly, and non-discriminatory 
manner.  This is an urgent issue that requires prompt attention.14 
 
On June 18, 2026, the Commission issued the Show Cause Order.15  The Show Cause Order 
recognizes the unprecedented increase in requests for transmission service to serve Large Loads 
along with the growing interest in co-location arrangements to serve those Large Loads.16  As 
relevant to this filing, the Show Cause Order finds that MISO’s Tariff appears to be unjust and 
unreasonable because it lacks provisions addressing ongoing operational requirements for 
transmission customers taking transmission service on behalf of Large Loads.17  The Show Cause 
Order raises concerns that MISO’s Tariff does not require transmission customers to provide MISO 
hourly forecasts, telemetry data, and other data to ensure sufficient visibility or specify 
requirements for maintaining communication channels between MISO and the transmission 
customer on behalf of the Large Load.18  In addition, the Show Cause Order raises concerns that 
MISO’s Tariff does not specify ramp rate or ride-through requirements with which the transmission 
customer taking transmission service on behalf of the Large Load must comply.19  This filing 
proposes Tariff revisions establishing necessary ongoing operational requirements for Large Loads 
in response to the concerns stated in the Show Cause Order. 
 
12  Accelerating Federal Permitting of Data Center Infrastructure, Executive Order 14318, 90 FR 35385 (July 23, 
2025), https://www.whitehouse.gov/presidentialactions/2025/07/accelerating-federal-permitting-of-data-center-
infrastructure/.  
13  Letter from C. Wright, Secretary of Energy, to the Federal Energy Regulatory Commission, Docket No. RM26-
4-000 (Oct. 23, 2025).  
14  Letter from C. Wright, Secretary of Energy, to the Federal Energy Regulatory Commission, Docket No. RM26-
4-000 (Oct. 23, 2025).  
15  See generally Show Cause Order.  
16  Id. at P 1.  
17  Id. at P 64.   
18  Id. at P 64.  
19  Id. at P 64.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 7 
 
 
 
B. 
Addressing the Influx of Large Loads in the MISO Region 
 
As noted above, the MISO region is experiencing a significant increase in both the scale 
and pace of Large Load development.  As indicated in the chart below, MISO’s 2026 Long-Term 
Load Forecast indicates that the region is experiencing load growth at levels not seen in decades, 
driven in large part by unprecedented large load activity and accelerating project announcements.20  
Data centers and advanced manufacturing are among the primary drivers of this growth, with some 
projects seeking to develop on timelines significantly shorter than those traditionally associated 
with generation and transmission infrastructure.  This combination of increased volume and 
accelerated development is changing the manner in which MISO must plan for and reliably 
integrate new load. 
 
 
 
Recent whitepapers and alerts published by the NERC Large Loads Task Force and Large 
Loads Working Group identify emerging Large Loads as an increasing reliability consideration for 
the Bulk Electric System.21  NERC guidance highlights that traditional planning and operational 
assumptions developed for conventional load may not fully capture the behavior or reliability 
impacts of emerging large loads, particularly as load facilities become larger, capable of rapid 
demand changes , and increasingly interconnected with power-electronic equipment.  
 
 
20  See MISO’s 2026 Long-Term Load Forecast (updated August 17, 2026), available at: 
https://cdn.misoenergy.org/20260513%20LTLF%20Whitepaper757916.pdf. 
21  See generally, Essential Action to Industry – Computational Load Modeling, Studies, Instrumentation, 
Commissioning, Operations, Protection, and Control, NERC (May 4, 2026), available at 
https://www.nerc.com/globalassets/programs/bpsa/alerts/level-3-computational-load-alert.pdf; Draft large Load 
Disturbance Performance, NERC (Dec. 10, 2026), available at https://www.nerc.com/globalassets/who-we-
are/standing-committees/rstc/llwg/draft_llwg_white_paper_large_load_disturbance_performance_tosubmit.pdf;  
Project 2026-02 Computational Load, NERC, https://www.nerc.com/standards/reliability-standards-under-
development/2026-02-computational-loads (last visited Aug. 27, 2026).

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 8 
 
 
Accommodating accelerated interconnection of Large Loads requires MISO to ensure that 
it can reliably plan for and operate the Transmission System as these facilities come online.  Key 
reliability considerations include sufficient visibility into Large Load characteristics and operating 
behavior, accurate forecasting and modeling, and requirements that address operational risks, such 
as rapid change in Demand, disturbance response, including ride-through capability.    
 
MISO, its member States, and a broad and diverse group of stakeholders have been 
developing multiple initiatives to address evolving system conditions and to support efficient and 
reliable interconnection of Large Loads prior to and after the issuance of the Show Cause Order.  
For example, MISO recently implemented the Expedited Resource Addition Study (“ERAS”) as a 
targeted, temporary process to issue a Generator Interconnection Agreement in three months.  
MISO also improved its Transmission Expansion Plan’s EPR process to quickly approve 
transmission upgrades necessary to address urgent needs associated with the addition of Large 
Loads.  Further, MISO initiated the MISO-SPP Joint Targeted Interconnection Queue Study 
(“JTIQ”), which aims at building transmission network upgrades along the MISO-SPP seams to 
enable large amounts of new generation to come online in a more timely manner.   
     
While these initiatives provide important benefits, they do not fully address the reliability 
and operational challenges associated with accelerating Large Load growth.  Existing planning 
reforms primarily focus on generation additions and transmission development timelines.  
Likewise, broader reliability initiatives were not specifically designed to address the unique 
characteristics and operational challenges presented by Large Load and Computational Load 
additions.  As the size and concentration of these facilities increase, additional visibility into load 
behavior and system interactions is necessary to support reliable operation of the Transmission 
System.  
 
Accordingly, MISO recognizes that additional Tariff-based solutions are necessary to 
establish clear reliability expectations, improve operational visibility, and facilitate timely 
integration of Large Loads in a manner that is both reliable and non-discriminatory.  These 
solutions must also consider and address the unique planning and operational characteristics of 
Large Load interconnection customers and hyperscale data centers, in particular.    
 
MISO is moving quickly and engaging with stakeholders through the Large Load Working 
Group (“LLWG”), as well as with the Organization of MISO States, Inc. (“OMS”), in an expedited 
manner to develop the broader set of solutions outlined in the August 3, 2026, motion filed by 
MISO and the MISO Transmission Owners to hold all proceedings related to the Show Cause 
Order in abeyance for 90 days.22  The Abeyance Motion explained that MISO and the MISO 
Transmission Owners required additional time to continue the stakeholder process and submit FPA 
 
22  Motion of the Midcontinent Independent System Operator, Inc. and the MISO Transmission Owners to Hold 
Proceeding in Abeyance and Request for Shortened Comment Period and Expedited Treatment, Docket No. 
EL26-70-000 (Aug. 3, 2026) (“Abeyance Motion”).

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 9 
 
 
section 20523 filings that address the concerns raised in the Show Cause Order.24  The Commission 
granted the 90-day abeyance requested in the Abeyance Motion on August 14, 2026.25    
 
MISO has developed a prioritized work plan to accelerate consideration of the challenges 
presented by Large Load growth in the MISO region through its stakeholder process.26  This 
process has resulted in the development of the IRR Proposal as well as ongoing discussion of 
additional solutions and improvements to various MISO processes, which MISO intends to submit 
for Commission review in a series of future Federal Power Act section 205 filings.27 
III. 
OVERVIEW OF THE IRR PROPOSAL AND HOW IT ADDRESSES THE SHOW CAUSE ORDER 
The IRR Proposal establishes broad categories of reliability requirements intended to 
address planning, operational and disturbance performance associated with Large Loads, along 
with new definitions, applicability and transition provisions necessary to implement the new 
requirements.  A brief overview of each component of the filing is summarized below: 
 
• 
Definitions and Applicability: Establishes which facilities qualify as Large Loads and 
Computational Loads and identifies when the requirements apply. 
 
• 
Data Requirements: Establishes the facility and operational information MISO needs 
to understand Large Load characteristics and expected behavior. 
 
• 
Model Requirements: Requires appropriate electrical models so Large Loads can be 
accurately represented in MISO planning and operational analyses. 
 
• 
Telemetry Requirements: Provides real-time visibility into Large Load demand and 
operating conditions to support reliable system operations. 
 
• 
Forecasting Requirements: Establishes short-term and other forecast information 
needed to anticipate Large Load demand and operating changes. 
 
• 
PMU Requirements for Computational Loads: Provides high-resolution, time-
synchronized measurements to support disturbance analysis, model validation, and 
performance verification. 
 
 
23  16 U.S.C. § 824d.  
24  Abeyance Motion at 2.  
25  Midcontinent Independent System Operator, Inc., et. al., 196 FERC ¶ 61,133 (August 14, 2026) (“Abeyance 
Order”). 
26  Id. at 4.  
27  Id.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 10 
 
 
• 
Ramp Requirements for Computational Loads: Establishes limits on rapid increases 
or decreases in demand during stable-state transitions to help manage operational 
impacts. 
 
• 
Ride-Through Requirements for Computational Loads: Establishes minimum 
voltage and frequency disturbance-performance expectations to reduce unnecessary 
disconnection and sudden load loss. 
 
• 
Implementation and Transitional Provisions: Establishes compliance timing, 
responsibilities, and transition mechanisms for existing and developing facilities. 
 
MISO further notes that this filing incorporates a proposed Tariff definition of “Large 
Load.”  This proposed definition is intended to apply to this filing as well as the other filings in 
response to the Show Cause Order, as applicable.  
A. 
New Definitions Related to the IRR for Large Load 
 
 
1. 
Large Load 
The Order posits that MISO’s Tariff appears to be unjust and unreasonable because it lacks 
a definition of Large Load sufficient to capture loads that present the unique challenges associated 
with Large Loads.28  This filing proposes to address the Order’s concern by implementing a clear 
and consistent Large Load definition, as follows:   
Large Load:  Load with Demand of 50 MW or more associated with 
any facility or aggregation of facilities located at a single substation 
behind one or more Point(s) of Withdrawal from the Transmission 
System that is owned, operated, or controlled by: (a) a single entity 
or (b) a group of entities that will coordinate with respect to the 
profile of the Load.  Large Load does not include Load used 
exclusively for charging an Electric Storage Resource. 
 
As explained by Ms. Li, MISO developed the proposed Large Load definition through a 
review of emerging industry practices, consideration of the reliability needs in the MISO region, 
and stakeholder feedback.29  Based on that review, MISO selected a 50 MW threshold as a 
reasonable and administratively clear starting point, consistent with industry precedent and 
sufficiently significant to warrant application of MISO’s Large Load requirements.  The definition 
is based on gross load rather than net load so that MISO has visibility into the full electrical demand 
and characteristics of the facility.  Further, MISO defined Large Load at the facility or site level to 
allow loads under common ownership or coordinated operational control at a single site to be 
considered together, including where the site is served through multiple points of interconnection.  
 
28  Show Cause Order at P 57. 
29  Li Testimony at p 12-13.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 11 
 
 
In addition, Load used exclusively for charging an Electric Storage Resource is excluded as such 
Load does not create the operational challenges associated with industrial and Computational 
Load.30 
 
2. 
Computational Load 
This filing also proposes a new definition of Computational Load in order to further support 
the consistent interpretation of the proposed reliability framework described in this filing, as 
follows: 
Computational Load: Large Load comprised of 25 MW or more of 
Demand from information technology equipment, such as servers, 
storage, and networking hardware. 
As explained by Ms. Li, the Computational Load definition distinguishes a subset of Large Loads 
that may exhibit operational characteristics different from more traditional loads, including rapid 
changes in demand, highly coordinated control behavior, and power-electronic responses during 
system disturbances.31  This distinction allows MISO to apply certain incremental requirements—
such as Ramp, PMU, and Ride-Through requirements—only where those characteristics warrant 
additional reliability consideration.  The Computational Load definition is necessary as certain 
proposed requirements are intended to apply only to Large Loads with operating characteristics 
that warrant additional reliability consideration.  Computational Loads may exhibit rapid and 
coordinated changes in demand, significant power-electronic behavior, and distinct responses to 
Transmission System disturbances.  Defining Computational Load supports a more targeted and 
risk-informed approach, rather than applying the same requirements to all Large Loads regardless 
of facility type or operating behavior.   
B. 
Applicability of the Interconnection Reliability Requirements 
 
The requirements in this filing will apply to Large Loads as established in the MISO Tariff 
and the Business Practices Manual for Large Load.  Subject to the transition provisions discussed 
below, all Large Loads will be subject to the applicable visibility requirements including: Basic 
Facility Data, Modeling, Telemetry, Forecast Data, and Audit requirements.  In addition, the 
Computational Load component of a Large Load, as defined in the Tariff, is subject to the PMU, 
Ride-Through, and Ramp requirements.  MISO recognizes that not all Large Loads present the 
same reliability risks and has limited the application of PMU, Ramp, and Ride-Through 
requirements to the Computational Load component of a Large Load, which reflects the increased 
operational risk Computational Loads place on the Transmission System.  Ms. Li explains that the 
IRR Proposal is intended to provide a scalable and risk-informed framework that may be applied 
 
30  Exclusion of Load used exclusively for charging an Electric Storage Resource is consistent with the definition 
of High Impact Large Load accepted by the Commission in Southwest Power Pool, Inc., 194 FERC ¶ 61,031, 
Order Accepting Tariff Revisions, Subject to Condition (Issued January 14, 2026).  
31  Li Testimony at p 13-14.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 12 
 
 
in a manner proportional to demonstrated reliability need, system conditions, and facility 
characteristics.32 
 
The Transmission Customer taking Transmission Service on behalf of a Large Load will 
be responsible for ensuring compliance by the Large Load with each of the applicable requirements 
set forth in the new Tariff section 37A.33  Requiring the Transmission Customer to ensure 
compliance with the requirements established in the IRR Proposal is consistent with the Show 
Cause Order’s discussion of imposing requirements on an “Eligible Customer” and recognizes that 
the ultimate owner of a Large Load may not participate directly in MISO’s markets or otherwise 
have contractual privity to MISO.  All Large Loads interconnected to the Transmission System, 
however, will be required to procure Transmission Service, through a Transmission Customer, 
pursuant to the Tariff.  As such, the Transmission Customer will be required to enter into a 
Transmission Service agreement, which incorporates by reference the terms of the Tariff, including 
the requirements proposed herein.  As a result, applying the requirements established in the IRR 
Proposal to a Transmission Customer taking Transmission Service on behalf of a Large Load 
establishes a legally enforceable framework though which all reliability requirements imposed on 
a Large Load may be enforced. 
The Show Cause Order indicates that MISO’s Tariff appears to be unjust and unreasonable 
because it lacks  pro forma provisions in a transmission service agreement between MISO and the 
transmission customer taking transmission service on behalf of a large load to memorialize the 
ongoing operational requirements similar to those proposed herein.34  The Commission notes that, 
without such  pro forma provisions in a transmission service agreement between MISO and the 
transmission customer, MISO may be unable to enforce ongoing operational requirements for 
transmission customers taking transmission service on behalf of large loads, and states that MISO 
should explain whether the Tariff remains just and reasonable without such pro forma provisions 
in a transmission service agreement, or propose revisions to include pro forma provisions 
memorializing the ongoing operational requirements in a transmission service agreement between 
MISO and the transmission customer.35  
In response to these concerns, MISO notes that the existing pro forma agreements for 
Transmission Service under MISO’s Tariff already incorporate the Tariff by reference.36 As such, 
 
32  Li Testimony at p 17. 
33  The term “Transmission Customer” is currently defined in the Tariff as: Any Eligible Customer (or its Designated 
Agent) that (i) executes a Service Agreement, or (ii) requests in writing that the Transmission Provider file with 
the Commission, a proposed unexecuted Service Agreement to receive Transmission Service under Module B of 
this Tariff. This term is used in the Module A, Common Tariff Provisions to include customers receiving 
Transmission Service under Module B of this Tariff, including any customer receiving HVDC Service. 
34  Show Cause Order at P 65. 
35  Id. 
36  See MISO Tariff, Attachment A – Form of Service Agreement for Short-Term Firm Point-to-Point Transmission 
Service at 6.0 (The Tariff and any applicable Transaction Specification Sheet are incorporated herein and made 
a part hereof.), Attachment A-1 - Form of Service Agreement for Long-Term Firm Point-to-Point Transmission 
Service at 6.0 (The Tariff and any applicable Transaction Specification Sheet are incorporated herein and made

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 13 
 
 
the Tariff will incorporate the requirements proposed herein in the applicable transmission service 
agreement for Transmission Service provided pursuant to the Tariff.  In addition, the Tariff is being 
amended pursuant to Federal Power Act Section 205, which is an open, transparent process that 
provides notice to the Transmission Customer of proposed changes to the Tariff that will apply on 
the requested effective date.37  As such, the Commission’s concerns are addressed by the 
incorporation clause in the applicable transmission service agreements and that further revising 
the pro forma agreements to detail additional requirements would be unnecessary and disregard 
the flexibility afforded by the existing agreements.38  This approach would also depart from prior 
practice and Commission precedent because it could result in assumed one-off application or 
requirements through the individual service agreement instead of the Tariff. 
C. 
Transition Provisions 
The Order states that any filing by MISO to address the Order’s directives should “(a) 
propose a reasonable implementation period to ensure minimal disruption to such existing 
commercial arrangements, and (b) allow a reasonable amount of time to finalize ongoing 
agreements that are nearing completion as of the date such Tariff provisions are filed with the 
Commission.  Such proposed Tariff revisions should include a reasonable effective date that 
accommodates such considerations regarding these existing commercial arrangements.”39   
Ms. Li provides that the IRR Proposal includes transition provisions that are intended to 
provide certainty to existing commercial arrangements and commercial arrangements that were 
near completion as of the date of this filing.40  The requirements consider the Service 
Commencement Date of the Transmission Service to serve a Large Load, whether transmission 
projects or upgrades associated with the Large Load have been approved by the MISO Board in 
 
a part hereof.), Attachment B - Form of Service Agreement for Non-Firm Point-to-Point Transmission Service 
at 8.0 (The Tariff and any applicable Exhibit WDS are incorporated herein and made a part hereof.), and 
Attachment F - Form of Service Agreement for Network Integration Transmission Service at 7.0 (The Tariff, 
Transaction Specification Sheet, Network Operating Agreement and Exhibit WDS are incorporated herein and 
made a part hereof.).  
37  See, e.g., W. Deptford Energy, LLC v. FERC, 766 F.3d 10 (D.C. Cir. 2014) (discussing the “notice exception” to 
the filed rate doctrine the general rule that parties may be impacted by tariff revisions even without amendments 
to their contracts). 
38  The Commission’s regulations further support this distinction between a service agreement and the tariff under 
which service is provided. Under 18 C.F.R. § 35.2(c)(2), a “service agreement” is an agreement that “authorizes 
a customer to take electric service under the terms of a tariff.” Thus, the service agreement does not necessarily 
fix the governing tariff as of the date of execution; rather, it authorizes service under the applicable tariff. That 
framework is reinforced by 18 C.F.R. § 35.28(c)(1) which requires transmission providers to maintain an OATT 
based on the Commission’s pro forma tariff “as amended from time to time,” and § 35.28(c)(4) specifically 
requires Commission-approved ISOs and RTOs to file revisions to their OATTs required by subsequent 
Commission rulemakings. Accordingly, the regulations contemplate that the tariff governing transmission 
service will continue to change after individual service agreements have been executed. See 18 C.F.R. §§ 
35.28(c)(1) and (c)(4). 
39  Show Cause Order at P 5. 
40  Li Testimony at p 18-19.

The Honorable Debbie-Anne Reese 
August 28, 2026 
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MTEP 2026, or a prior MTEP, and when transmission projects or upgrades associated with the 
Large Load has been submitted to the MISO EPR process.  This proposed approach recognizes the 
existing commercial arrangements and more immediate, non-speculative, nature of the Load 
additions and associated Transmission System upgrades. 
The IRR Proposal proposes the following definition of “MTEP/EPR Condition” to 
facilitate the transition provisions proposed in this filing: 
• 
For purposes of the transition provisions, Load will satisfy the “MTEP/EPR Condition” 
if it is associated with a transmission project that either: (a) has been approved by the 
MISO Board in MTEP 2026, or a prior MTEP; or, (b) has been submitted to MISO for 
EPR on or prior to June 18, 2026, in accordance with Attachment FF of the Tariff. 
Based on this newly defined term, MISO proposes to implement the following three 
transition provisions through the IRR Proposal:  
First, MISO proposes to fully exempt, or “grandfather,” any Large Load that has a Service 
Commencement Date on or prior to December 4, 2026, from all requirements of the proposed 
Section 37A, with respect to the portion of the Large Load that has procured Transmission Service 
as of the Service Commencement Date.  Any modification or series of modifications to a Load that 
meets the MTEP/EPR Condition, which results in a cumulative increase of 25 MW or more in 
Transmission Service for such Load and with a Service Commencement Date after December 4, 
2026, may subject the additional Load to certain requirements, depending on METP / EPR 
approval date and the Service Commencement Date of the Transmission Service for the additional 
Load. 
 
Second, MISO proposes that a Large Load, or a portion of a Large Load, that does not have 
a Service Commencement Date prior to December 4, 2026, but that meets the MTEP/EPR 
Condition shall be subject to the visibility requirements set forth in Sections 37A.1 through 37A.5 
and Section 37A.8, and shall be exempt from the ramp and ride-through requirements set forth in 
Sections 37A.6 through 37A.7.   
 
Third, MISO proposes that a Large Load, or a portion of Large Load, that does not have a 
Service Commencement Date prior to December 4, 2026, and that has not met the MTEP/EPR 
Condition, but has submitted Load associated with a transmission project to MISO for EPR on or 
after June 19, 2026, but on or before October 31, 2026, shall be subject to all requirements set 
forth in this Section 37A, provided that MISO may waive the ride-through requirements set forth 
in Section 37A.6 based upon a determination that: a) exemption from such requirements would 
not have an adverse reliability impact; and, b) compliance with such requirements would result in 
significant costs. 
 
A Large Load that does not satisfy any of these transition provisions will be subject to all 
applicable reliability requirements, depending on whether the Large Load also qualifies as 
Computational Load.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 15 
 
 
D. 
The Ongoing Operational Requirements for Transmission Customers Taking 
Service on Behalf of Large Loads  
The Order posits that MISO’s Tariff appears to be unjust and unreasonable because it lacks 
provisions addressing ongoing operational requirements for transmission customers taking 
transmission service on behalf of Large Loads.41  The Order identified several data and other 
operational requirements it states were absent from the Tariff, including: (i) hourly forecasts, 
telemetry data, and other data to ensure sufficient visibility or specify requirements for maintaining 
communication channels between MISO and the transmission customer on behalf of the Large 
Load; (ii) equipment to enable MISO to monitor Large Loads for impacts of, for example, fast-
ramping load that may impact the transmission system too quickly to be captured by conventional 
data acquisition systems (e.g., phasor measurement units or similar); and (iii) specified ramp rate 
or ride-through requirements.42  The Order also stated that MISO’s Tariff lacks pro forma 
provisions in a transmission service agreement between MISO and the transmission customer 
taking transmission service on behalf of a Large Load to memorialize the above terms (e.g., 
equipment requirements, data requirements, remote disconnect capability).43 
1. 
Basic Facility Data and Modeling Requirements 
 
a. 
Reliability Objective 
Ms. Li provides that the objective of the data and modeling requirements is to ensure 
sufficient visibility into the characteristics, operating behavior, and electrical performance of Large 
Loads necessary to support reliable planning, interconnection, commissioning, operations, and 
post-event analysis.44  As emerging Large Loads increasingly exhibit dynamic operating 
characteristics, power-electronic interfaces, and concentrated demand, additional facility 
information, telemetry, and modeling detail may be necessary to evaluate reliability impacts under 
both normal and contingency conditions.  Data and modeling requirements are intended to support 
reliable operation of the Transmission System by improving the accuracy of planning assumptions, 
strengthening operational awareness, supporting disturbance analysis and model validation, and 
enabling more consistent evaluation of system performance associated with Large Load 
integration.  These requirements provide a framework for obtaining facility information, electrical 
models, telemetry, monitoring data, and operational visibility necessary to support planning 
studies, operational assessments, commissioning activities, and reliability evaluations. 
 
Consistent with emerging industry practices and North American Electric Reliability 
Corporation (“NERC”) guidance, data and modeling expectations are intended to be scalable and 
 
41  Show Cause Order at P 64. 
42  Id. 
43  Id. at P 65. 
44  Li Testimony at p 24.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 16 
 
 
risk-informed and may vary based on facility characteristics, operating behavior, system 
conditions, and demonstrated reliability need. 
b. 
Applicable Requirements 
 
i. Facility Data 
The Transmission Customer will be responsible for providing MISO with basic 
information, one-line diagrams, and a description of the electrical characteristics of the Large Load 
for all Large Load Equipment, in the format and consistent with the timelines specified in the 
Business Practice Manual for Large Load.  Any changes to the characteristics of a Large Load 
and/or Large Load Equipment, including any changes to the modeling details for the Large Load, 
shall be provided to MISO in a timely manner, consistent with the Business Practices Manual for 
Large Load.  Such changes may include, but are not limited to, Load MW amounts, firm and non-
firm MW amounts, any dispatchable Load MWs, power factor, metering, telemetry, breaker 
configuration, staged additions and annual energy as further set forth in the Business Practices 
Manual for Large Load.  
 
The Transmission Customer must coordinate with the Transmission Owner where the 
Large Load Point of Withdrawal is located pursuant to MISO’s load interconnection guidance and 
applicable NERC standards. 
 
Together, these requirements help ensure that MISO has current and accurate facility 
information to support planning and reliable operation of the Transmission System.45 
 
ii. Modeling Data 
The Transmission Customer will be responsible for providing MISO with verified and 
complete electrical models of the Large Load, as well as detailed Load profiles, for modeled Loads, 
in the format and consistent with the timelines specified in the Business Practice Manual for 
Transmission Planning.  Such model information must include sufficient detail for MISO to 
evaluate system performance under contingency conditions in accordance with currently active 
versions of Transmission System Planning Performance Standards. 
 
Following completion of applicable studies and prior to the Service Commencement Date 
of the Large Load, the Transmission Customer will be responsible for providing final verified 
models to MISO in accordance with the Business Practices Manual for Large Load. The 
Transmission Customer will be responsible for providing notice to MISO of any material 
modifications to the Large Load and shall not implement any such proposed modifications until 
studied and approved by MISO in accordance with the Business Practices Manual for Large Load.   
 
 
45  Li Testimony at p 24.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 17 
 
 
The final models of a Large Load shall reflect the as-built configuration and actual 
operating characteristics of the Large Load and Large Load Equipment.  The Transmission 
Customer shall maintain and update models as required by MISO. 
Together, these requirements help ensure that MISO’s planning and reliability studies are 
based on current and representative Large Load models. 
2. 
Load Forecasting Requirements 
 
a. 
Reliability Objective 
Ms. Li explains that Demand from Large Loads can fluctuate rapidly due to operational 
processes, making system conditions difficult to predict solely from historical weather or calendar 
data .46  To preserve reliable commitment and dispatch, Transmission Customers serving Large 
Loads must provide timely, granular, and continuously updated short-term forecasts that MISO 
can ingest at CPNode level and use across Reliability Assessment Commitment (RAC) and 
Security Constrained Economic Dispatch (SCED) processes, along with other reliability studies.  
These submissions give operators forward visibility into expected demand, enabling risk-aware 
commitment, real-time balancing, reserve sufficiency, and local reliability under changing system 
conditions. 
 
 
b. 
Applicable Requirements 
Prior to the later of the Service Commencement Date of a Large Load or September 1, 
2027, the Transmission Customer must provide day(s) ahead and real-time Load Forecasts for a 
Large Load directly to MISO to support the RAC and SCED processes, along with other reliability 
studies.  Given the sizable reliability impact a Large Load may have on the Transmission System, 
the Load Forecasts shall be updated to reflect the most current information on the expected 
Demand, in accordance with the Business Practices Manual for Large Load. 
3. 
Telemetry and Phasor Measurement Unit (PMU) Requirements 
 
a. 
Reliability Objective 
Ms. Li explains that the objective of telemetry and PMU requirements is to ensure that 
MISO and Transmission Owners maintain real-time, continuous, high‑resolution visibility into 
Large Load behavior through accurate SCADA/ICCP data and time‑synchronized phasor 
measurements.47   
Because emerging Large Loads can change real and reactive power rapidly and exhibit 
power‑electronic‑driven dynamic responses during disturbances, telemetry and, at a minimum, 
PMU live streaming enable operators to identify abnormal voltage, frequency, or oscillatory 
 
46  Li Testimony at p 26. 
47  Li Testimony at p 26-28.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 18 
 
 
conditions early, validate and refine modeling assumptions, support balancing and contingency 
analysis, and respond effectively before issues propagate across the Bulk Electric System.  
Reliable, real‑time telemetry strengthens MISO’s ability to manage system stability, operational 
uncertainty, and disturbance performance under both normal and stressed conditions, ensuring that 
Large Loads integrate safely and predictably into the grid. 
MISO addressed several considerations to support the telemetry reliability objective, 
including the following: 
• Sampling Rate and Data Quality: High‑resolution sampling (e.g., PMU‑level >60 samples 
per second) is necessary to capture fast voltage, frequency, and real/reactive power changes 
characteristic of power‑electronic Large Loads. 
• SCADA/ICCP Update Frequency: SCADA telemetry should provide sufficiently frequent 
updates to support operational situational awareness and real‑time reliability assessments. 
• Phasor Measurement Unit (PMU) Integration: PMUs should be installed at the 
Transmission Owner side of the Point of Withdrawal to capture time‑synchronized 
voltage/current phasors and event signatures that SCADA cannot detect. 
• Location of Telemetry Measurement Devices: Telemetry equipment should be installed at 
Point of Withdrawal. 
• Communications 
Infrastructure 
& 
Latency: 
Sufficient 
bandwidth, 
redundant 
communication paths, and low latency data streaming are essential for ensuring real‑time 
visibility, especially for PMU data that should remain tightly time‑aligned. 
• Time Synchronization Requirements: PMUs should maintain GPS‑quality time 
synchronization to support system‑wide correlation of events and dynamic monitoring. 
• Compatibility with MISO Telemetry Specifications: All telemetry should align with 
MISO’s ICCP, PMU streaming, and EMS data validation requirements as documented in 
relevant BPMs and LLWG guidance. 
 
b. 
Applicable Requirements 
MISO is proposing to implement the following Telemetry and PMU requirements and 
procedures applicable to Large Load Customers: 
 
1. Prior to the later of the Service Commencement Date of a Large Load or September 1, 
2027, a Transmission Customer must provide real-time telemetry for the Large Load, either 
directly, through the applicable Transmission Owner, or other Transmission Provider-
approved communication path, in the form and manner as set forth in the Business Practices 
Manual for Large Load. 
 
2. Individual metering will be required for all Large Load and any Generation Resource(s) 
serving such Large Load that is located behind the same Point of Interconnection to the

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 19 
 
 
Transmission System as the Large Load and meeting thresholds outlined in the Business 
Practices Manual for Large Load.  All telemetry shall be provided via Inter-Control Center 
Communications Protocol (ICCP) and must meet Transmission Provider update 
requirements as specified in the Business Practices Manual for Large Load.  The 
Transmission Customer must use commercially reasonable efforts to maintain telemetry 
availability and accuracy for the Large Load and must promptly correct erroneous data, 
bad mappings, and ICCP modeling issues. 
 
3. The Transmission Owner must provide disturbance monitoring and event recording 
capability sufficient to support post-event analysis, model validation, and reliability 
assessment. 
 
In addition to the requirements described above, Computational Load will be subject to the 
following Phasor Measurement Unit (PMU) requirements.  Prior to the later of the Service 
Commencement Date of a Large Load or September 1, 2027, phasor measurement recording and 
communications equipment that is capable, at a minimum, of gathering phasor measurements must 
be installed as specified in Business Practices Manual for Large Load.  To the extent similar quality 
equipment is being added or already exists, such as relays or digital fault recorders, that can collect 
data at least at the same rate as PMU and which data is synchronized via a high-accuracy satellite 
clock, such equipment may be utilized to satisfy this requirement if the equipment is located on 
the Transmission Owner’s side of the Point(s) of Withdrawal. The phasor measurement equipment 
must be installed at the Transmission Owner’s side of the Point(s) of Withdrawal, at the 
Transmission Customer’s expense, and become part of the Transmission Owner interconnection 
facilities.   
4. 
Ramp Requirements 
 
a. 
Reliability Objective 
Ms. Li provides that the reliability objective of the ramp requirements is to manage 
operational impacts that can result when a Computational Load increases or decreases its Demand 
rapidly during stable-state transitions.48  Computational Loads may have the capability to change 
significant amounts of demand over a relatively short period of time and, in some cases, to do so 
in a highly coordinated manner.  Rapid changes of this magnitude can create short-term supply-
demand imbalances, cause sudden changes in transmission power flows, and increase the 
operational actions needed to maintain reliable system conditions. 
 
Establishing reasonable limits on the rate at which a Computational Load may increase or 
decrease its Demand provides an established operating envelope within which MISO can maintain 
generation-load balance and ensure the coincident risk of multiple Computational Loads does not 
result in broader reliability impacts. 
 
 
48  Li Testimony at p 30-31.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 20 
 
 
The proposed ramp requirements are intended to ensure that changes in Computational 
Load demand occur at a rate that can be reliably accommodated by the Transmission System.  The 
requirements establish up- and down-ramp limits during stable-state transitions, measured in 
aggregate across the applicable Points of Withdrawal, while allowing eligible generation or other 
resources to provide ramp smoothing.  MISO is proposing initial up- and down-ramp limits of 
30MW/minute.     
 
 
 
b. 
Applicable Requirements 
Computational Load will be subject to up-ramp and down-ramp limits during the stable-
state transitions, measured in aggregate across the applicable Point(s) of Withdrawal, while 
allowing eligible generation or other resource to provide ramp smoothing, consistent with the 
process set forth in the Business Practices Manual for Large Load.  The process to establish up-
ramp and down-ramp limits for a Computational Loads will consider local planning criteria and 
will include a procedure for MISO to authorize or instruct deviations as may be needed to preserve 
reliability. 
5. 
Ride-Through Requirements 
 
 
a. 
Reliability Objective 
Ms. Li explains that the objective of ride-through requirements is to reduce the risk of 
unnecessary Computational Load disconnection or rapid changes in Demand during voltage and 
frequency disturbances and support predictable disturbance performance during credible 
Transmission System events.49  As emerging Large Loads increasingly include power-electronic 
interfaces, fast controls, and dynamic operating behavior, disturbance response may materially 
affect system performance, operational reliability, and post-contingency recovery. 
 
Ride-through requirements are intended to support reliable operation of the Transmission 
System by improving disturbance resilience, reducing operational uncertainty associated with 
sudden changes in Computational Load demand, and promoting more predictable facility behavior 
during transmission disturbances. These requirements establish minimum performance 
expectations for the Computational Load component of a Large Load to maintain connection and 
stable operation during voltage and frequency excursions, while supporting system voltage 
recovery, frequency performance, and overall system stability. 
 
Consistent with emerging industry practices and NERC guidance, the proposed ride-
through expectations are intended to establish scalable and reliability-based performance criteria 
proportional to demonstrated system risk and facility operating characteristics. 
 
 
b. 
Applicable Requirements 
 
49  Li Testimony at p 32.

The Honorable Debbie-Anne Reese 
August 28, 2026 
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i. 
General Principles  
Ride-through requirements apply at the facility’s Point(s) of Withdrawal (PoW(s)) and 
establish the voltage and frequency conditions under which a Computational Loads are required 
to remain connected to the Transmission System and continue operation during disturbances. 
When system conditions remain within the specified ride-through performance limits, 
Computational Loads are expected to remain connected and maintain stable operation without 
unnecessary interruption of service.  As Ms. Li notes, protection and control systems should be 
coordinated to avoid unnecessary tripping, and momentary cessation is not permitted unless 
explicitly allowed.  Following disturbance clearance, Computational Loads are expected to recover 
toward pre-disturbance operating conditions in a controlled manner consistent with established 
performance expectations.50 
Ms. Li explains that the Tariff revisions proposed herein establish the core ride-through 
obligations, while the technical basis and detailed application of performance criteria supporting 
the ride-through requirements are described in MISO’s published Large Load Technical 
Compendium, which will be incorporated into MISO’s Business Practices Manual for Large Load 
prior to the effective date of the IRR Tariff provisions.51  MISO is continuing to work with 
stakeholders on implementation details to be included in the BPM, which will address the 
following items: 
• Applicability: Applies to Computational Loads subject to MISO’s ride-through 
requirements. 
• Stay connected: Requires the facility to remain connected during qualifying voltage 
and frequency disturbances. 
• Stable operation: Requires the facility to maintain stable behavior during the 
disturbance and avoid unnecessary tripping. 
• Post-disturbance recovery: Requires active power to recover in a controlled manner 
that supports reliable Transmission System operation. 
• Demonstration of capability: Requires the Transmission Customer to provide models, 
studies, equipment information, testing, or other evidence demonstrating compliance. 
IV. 
DESCRIPTION OF PROPOSED TARIFF REVISIONS 
A. 
Module A (Common Tariff Provisions).  MISO is proposing to add several new 
terms and definitions to Module A, as follows: 
 
 
50  Li Testimony at p 32-33. 
51  Li Testimony at p 33-34.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 22 
 
 
1. Computational Load:  Large Load comprised of 25 MW or more of Demand 
from information technology equipment, such as servers, storage, and 
networking hardware.  
 
2. Large Load Equipment: Any of the facilities, devices, or equipment that 
constitutes a part of a Large Load, or are used to interconnect the Large Load 
to the Transmission System. 
 
3. Large Load:  Load with Demand of 50 MW or more associated with any facility 
or aggregation of facilities located at a single substation behind one or more 
Point(s) of Withdrawal from the Transmission System that is owned, operated, 
or controlled by: (a) a single entity or (b) a group of entities that will coordinate 
with respect to the profile of the Load.  Large Load does not include Load used 
exclusively for charging an Electric Storage Resource. 
 
4. Point(s) of Withdrawal:  The point(s) where a non-transmission facility that is 
used to withdraw Energy from the Transmission System to serve Load connects 
to the Transmission System. 
 
MISO respectfully submits that these proposed definitions are just, reasonable, and 
necessary to implement the IRR Proposal in a clear and consistent manner.  The terms were 
presented to stakeholders and iterated through MISO’s stakeholder process.  MISO worked with 
stakeholders on the definition of Large Load and related terms (i.e., Large Load Equipment, 
Point(s) of Withdrawal, and Computational Load) and refined those terms in response to 
stakeholder feedback.  The proposed terms represent a reasonable resolution of disputed issues 
relating to the definition of a “Large Load,” including considerations of the unique operational 
characteristics of Large Loads and the unique considerations within the MISO region.  The 
proposed terms also provide clarity to stakeholders, MISO, and the Commission as MISO works 
to fully address the concerns identified in the Order while ensuring that Large Loads interconnect 
in a reliable manner.  
 
B. 
Module B (Transmission Service).  MISO is requesting approval to add new 
provisions to Module B, as follows: 
 
1. Section 37A (Applicability of Large Load Reliability Requirements): MISO is 
proposing to implement a new subsection titled “Applicability of Large Load 
Reliability Requirements.”  This proposed subsection explains that all Large 
Load shall be subject to certain requirements as set forth in Sections37A.1 
through 37A.4 and section 37A.8 of the Tariff, which are discussed below.  The 
proposed subsection also explains that Computational Load shall be subject to 
the requirements in Sections 37A.5 through 37A.7 of the Tariff, described 
below.  Proposed Section 37A specifies that the Transmission Customer shall 
be responsible for complying with the requirements of Section 37A and shall 
demonstrate its ability to effectuate compliance with Section 37A.  Proposed

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 23 
 
 
Section 37A further explains that failure to comply with applicable 
requirements may result in a delayed Service Commencement Date, a period of 
time needed for corrective action, operational limitations, or other remediation 
action(s) by Transmission Provider as may be necessary to maintain 
Transmission System reliability.  This section also contains the Transition 
Provisions as discussed above.  
MISO proposes this Section 37A in order to implement clear guidelines as to the 
applicability of the proposed requirements and to identify responsible entities.  Because Large 
Load interconnections implicate multiple parties, clarity on those parties’ responsibilities and 
obligations is needed to streamline the interconnection process and ensure speed to power.  Further, 
clarity is required as to potential consequences in the event a party fails to comply with applicable 
requirements.  
2. Section 37A.1 (Large Load Information and Basic Facility Data Requirements): 
MISO is proposing a new subsection addressing Large Load information and 
basic facility data requirements.  This proposed subsection explains that the 
Transmission Customer is responsible for providing the Transmission Provider 
with basic information, one-line diagrams, and a description of the electrical 
characteristics of the Large Load for all Large Load Equipment, in the format 
and consistent with the timelines specified in the Business Practice Manual for 
Large Load.  The proposed subsection specifies that any changes to the 
characteristics of a Large Load and/or Large Load Equipment shall be provided 
to the Transmission Provider in a timely manner, consistent with the Business 
Practices Manual for Large Load.  The proposed subsection further clarifies that 
the Transmission Customer must coordinate with the Transmission Owner 
where the Lare Load Point(s) of Withdrawal is located pursuant to applicable 
interconnection guidance and NERC standards. 
MISO proposes this Section 37A.1 in order to clearly identify the Large Load information 
and basic facility data requirements needed to reliably interconnect a Large Load.  The proposed 
subsection clearly assigns responsibility among the Transmission Customer, Transmission 
Provider, and Transmission Owner, while assigning certain implementation details to the 
applicable Business Practice Manual.  MISO submits this subsection strikes a reasonable balance 
of providing sufficient guidance to applicable parties regarding the Large Load information and 
basic facility data requirements, while offering flexibility by leaving the implementation details to 
refinement in the Business Practices Manual.  
3. Section 37A.2 (Large Load Modeling Requirements): MISO is proposing a new 
subsection detailing the modeling requirements applicable to Large Loads.  This 
proposed subsection explains that the Transmission Customer shall provide the 
Transmission Provider with verified and complete electrical models of the 
Large Load, as well as detailed Load profiles, for modeled Loads, in the format 
and consistent with the timelines specified in the Business Practice Manual for 
Transmission Planning.  The proposed subsection clarifies that this model

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 24 
 
 
information must include sufficient detail for Transmission Provider to evaluate 
system performance under contingency conditions in accordance with currently 
active versions of Transmission System Planning Performance Standards.  The 
proposed subsection states that, following completion of applicable studies and 
prior to the Service Commencement Date of a Large Load, the Transmission 
Customer shall submit final verified models to the Transmission Provider in 
accordance with the Business Practices Manual for Large Load and provide 
notice to the Transmission Provider of any material modifications to the Large 
Load.  The proposed subsection states that the final models of a Large Load 
shall reflect the as-built configuration and actual operating characteristics of the 
Large Load and Large Load Equipment, which the Transmission Customer 
must maintain and update as required by the Transmission Provider. 
MISO proposes this Subsection 37A.2 to provide clear modeling requirements, while 
further addressing the implementation details of those models to the applicable Business Practices 
Manual.  The modeling requirements are reasonable and ensure that the Transmission Provider 
receives the information necessary to model a proposed Large Load interconnection request, while 
receiving updates to any relevant features of that proposed Large Load.  This proposed subsection 
strikes an appropriate balance of detail between the Tariff and implementation details in the 
Business Practices Manual by clearly assigning responsibility to the Transmission Customer for 
developing and providing modeling information, and updating its submission in response to 
changed circumstances.   
4. Section 37A.3 (Large Load Telemetry Requirements): MISO is proposing a 
new subsection detailing the telemetry requirements applicable to Large Loads.  
The proposed subsection specifies that telemetry must be in real-time, provided 
via an appropriate communication path, and submitted in the form and manner 
set forth in the Business Practices Manual for Large Load.  The proposed 
subsection states that individual metering will be required (both for Large Load 
and any Generation Resource(s) serving such Large Load at the same POI), and 
that all telemetry will be provided by via Inter-Control Center Communications 
Protocol (ICCP) and must meet Transmission Provider update requirements as 
specified in the Business Practices Manual for Large Load.  The subsection 
states that the Transmission Owner must provide disturbance monitoring and 
event recording capabilities. 
MISO proposes this Subsection 37A.3 to provide clear telemetry requirements, while 
affording the flexibility to address implementation details in the Business Practices Manual.  The 
telemetry requirements are reasonable and transparent, and provide sufficient visibility to ensure 
the reliable interconnection of a Large Load.  The proposed subsection provides an appropriate 
balance of detail between the Tariff and implementation details in the Business Practices Manual 
by identifying the requirements for telemetry and assigning responsibility to the applicable parties. 
5. Section 37A.4 (Large Load Forecast Data Requirements): MISO is proposing a 
new subsection detailing the forecast data requirements for a Large Load.  The

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 25 
 
 
proposed subsection provides that, before the Service Commencement Date of 
a Large Load or September 1, 2027 (whichever is later), the Transmission 
Customer must provide day(s) ahead and real-time Load Forecasts for a Large 
Load directly to the Transmission Provider to support the Reliability 
Assessment Commitment (RAC) and Security Constrained Economic Dispatch 
(SCED) processes, along with other reliability studies.  The Load Forecasts 
must be updated to reflect the most current information on the expected 
Demand, in accordance with the Business Practices Manual for Large Load. 
MISO proposes this Subsection 37A.4 to ensure that Transmission Customers provide 
sufficient forecast data for a Large Load to MISO to support reliability efforts.  The subsection 
also ensures MISO receives accurate, and up-to-date information by requiring the Transmission 
Customer to supplement its forecast data with the most current information.  The proposed 
subsection strikes the appropriate balance of providing all parties with sufficient detail regarding 
the proposed forecast data requirements while leaving implementation details to the Business 
Practices Manual. 
6. Section 37A.5 (Large Load Phasor Measurement Unit Requirements): MISO is 
proposing a new subsection detailing the PMU requirements for Large Loads.  
The proposed subsection states that Computational Load is subject to the PMU 
requirements.  The subsection requires PMU and recording information to be 
installed before the Service Commencement Date of a Large Load or September 
1, 2027 (whichever is later), and requires that this equipment gather the 
requirements specified in the Business Practices Manual.  The proposed 
subsections allow for the use of existing equipment to meet these requirements, 
provided that equipment can collect data at the same rate as PMU and which 
data is synchronized via a high-accuracy satellite clock.  The proposed 
subsection specifies that the PMU equipment must be installed at the 
Transmission Owner’s side of the Point(s) of Withdrawal and become part of 
the Transmission Owner interconnection facilities.   
MISO proposes this Subsection 37A.5 to implement PMU requirements for Large Loads.  
The subjection ensures that those PMU requirements are satisfied by either the installation new 
equipment or a demonstration that existing equipment can serve substantially the same purpose.  
The subsection thus strikes a reasonable balance of requiring the installation of new equipment 
with grandfathering existing equipment that serves substantially the same purpose.  The proposed 
subsection also strikes the appropriate balance of providing all parties with sufficient detail of the 
PMU requirements while leaving implementation details to the Business Practices Manual. 
7. Section 37A.6 (Large Load Ride-Through Requirements): MISO is proposing 
a new section for Large Load ride-through requirements.  The proposed 
subjection provides that Computational Load shall remain connected to the 
Transmission System and continue operation during voltage and frequency 
disturbances within the performance criteria established by the Transmission 
Provider in the Business Practices Manual for Large Load.  The proposed

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 26 
 
 
subsection also specifies that ride-through requirements apply at the Point(s) of 
Withdrawal and may include evaluation, testing, modeling, monitoring, and 
other compliance measures established by the Transmission Provider in the 
Business Practices Manual for Large Load. 
MISO proposes this Subsection 37A.6 to clearly delineate the ride-through requirements 
for Computational Load.  The proposed subsection provides clear guidance to Computational 
Loads and explains where those ride-through requirements will apply.  The proposed subsection 
also strikes the appropriate balance of providing all parties with sufficient detail of the ride-through 
requirements while leaving implementation details to the Business Practices Manual. 
8. Section 37A.7 (Large Load Ramp Requirements): MISO is proposing a new 
subsection to impose Large Load ramp requirements.  The proposed subsection 
states that Computational Load is subject to the requirements.  Ramp limits shall 
be measured in aggregate across the applicable Point(s) of Withdrawal during 
stable-state transition, including any reduction/ramp smoothing provided by 
generation or other resources that meets the eligibility requirements specified 
in the Business Practices Manual for Large Load.  Computational Load shall 
also be subject to up-ramp and down-ramp limits established by the 
Transmission Provider consistent with the process set forth in the Business 
Practices Manual for Large Load.  The proposed subsection states that the 
Computational Load must have an effective up and down ramp rate not 
exceeding the specified limit outlined in the Business Practices Manual for 
Large Load unless otherwise directed. 
MISO proposes this Subsection 37A.7 to clearly delineate the ramp requirements for Large 
Loads.  The proposed subsection clearly identifies those parties subject to the requirements (i.e., 
Computational Load), explains how ramp limits will be measured, and specifies that MISO shall 
establish up-ramp and down-ramp limits.  The proposed subsection also strikes the appropriate 
balance of providing all parties with sufficient detail of the ramp requirements while leaving 
implementation details to the Business Practices Manual. 
9. Section 37A.8 (Large Load Audit Rights): MISO is proposing a new subsection 
to implement Large Load audit rights.  The proposed subsection provides that 
the Transmission Provider has the right to audit or verify the information 
provided by a Transmission Customer for a Large Load and Large Load 
Equipment.  The proposed subsection states that the Transmission Customer 
shall maintain individual Large Load data and information related to the 
registration, Load Forecasts, operations, modeling, metering, and/or settlements 
for five (5) Years, while the Transmission Provider shall maintain individual 
Large Load data and information it receives related to the registration, Load 
Forecasts, operations, modeling, metering, and/or settlements for five (5) Years. 
MISO proposes this Subsection 37A.8 to clearly identify proposed Large Load audit rights.  
The subsection affords MISO the Tariff-defined authority to audit and verify information provided

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 27 
 
 
by a Transmission Customer for a Large Load, while ensuring that the information is preserved for 
at least five years.  The proposed subsection strikes a balance of ensuring that information is made 
available to MISO and preserved for a reasonable time to complete audits, when weighed against 
any costs and burdens associated with securing such data.  The proposed subsection also strikes 
the appropriate balance of providing all parties with sufficient detail of the audit rights while 
leaving implementation details to the Business Practices Manual. 
V. 
STAKEHOLDER ENGAGEMENT 
MISO has engaged in detailed discussions with stakeholders on Large Load issues since 
2024 in various stakeholder entities and workshops.  MISO first discussed Large Loads with 
stakeholders in the context of Expedited Project Review process improvements at the Planning 
Advisory Committee (“PAC”) and Planning Subcommittee (“PSC”) in 2024 and 2025.  Moreover, 
since 2024, MISO has discussed coordinating the MISO Transmission Expansion Plan and 
Definitive Planning Phases (“DPP”) processes to accommodate Large Loads at the PSC.  MISO 
additionally discussed Large Load citing methodology at the November 18, 2025, Futures 
Redesign Workshop. 
 
 
MISO introduced the Large Load Interconnection Reliability Requirements at the Large 
Loads Workshop on January 30, 2026.52  The workshop addressed the challenges associated with 
reliably interconnecting Large Loads, focusing on defining reliability requirements and improving 
the speed of integration while maintaining reliability to support member plans and goals.  
Following the January 30th workshop, MISO discussed the Large Load Interconnection Reliability 
Requirements at the PAC and the Large Load Working Group (“LLWG”).  A table of meetings 
involving MISO’s Large Load reliability requirements development, with links to meeting 
materials is provided as an attachment to Ms. Li’s testimony. 
 
 
At the February 25, 2026, PAC, MISO proposed a definition of Large Load and provided 
a high-level overview of the Large Load Interconnection Reliability Requirements.  MISO 
requested stakeholder feedback on the Large Load definition.  At the April 20, 2026, LLWG, MISO 
provided a revised Large Load definition based on stakeholder feedback and presented the Large 
Load Interconnection Reliability Requirements.  MISO requested feedback on the Large Load 
Interconnection Reliability Requirements.  At the April 22, 2026, PAC, MISO shared the revised 
Large Load definition that had been shared previously at the LLWG.  MISO additionally presented 
transition provisions it developed to address pending but unbuilt Large Load.  
 
 
At the May 14, 2026, LLWG, MISO responded to stakeholder feedback from the April 20 
LLWG meeting, provided proposed Tariff language for the Large Load Interconnection Reliability 
Requirements, and provided an updated Large Load definition.  In response to stakeholder 
feedback MISO revised the applicability language to provide additional clarity, included 
transitional provisions that offer flexibility during implementation, and incorporated a phased-in 
implementation to support readiness across customers and utilities.  MISO additionally updated its 
 
52  See Li Testimony, Attachment A – Table of Stakeholder Meetings.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 28 
 
 
Large Load definition based on stakeholder feedback.  Specifically, in response to stakeholder 
feedback regarding MISO’s initial proposal allowing multiple Points of Interconnection (“POI”), 
MISO proposed only allowing multiple POIs if the ZGIA is located at one of the stations, i.e. 
Points of Withdrawal of a Large Load Campus.  MISO requested feedback on the Large Load 
Interconnection Reliability Requirements Tariff draft.  At the May 27, 2026, PAC, MISO presented 
the updated Large Load definition, including the revisions to applicability and transitional 
provisions, to ensure clarity on implementation of Interconnection Reliability Requirements.  
 
 
At the June 10, 2026, LLWG, MISO responded to stakeholder feedback and presented the 
Tariff redlines for the Large Load Interconnection Reliability Requirements based on stakeholder 
feedback.  Stakeholder feedback significantly influenced the revised Tariff language, particularly 
around applicability, transition provisions, and requirement specific language.  Namely, MISO: (1) 
updated Tariff and BPM language to clarify treatment of existing loads, any expansions, and the 
applicability date; (2) updated the transitional provision to allow more flexibility; (3) updated the 
Applicability section to distinguish between Computational and Non-Computational Loads, and 
applied only ramp, PMU, ride-through, and advanced modeling requirements to Computational 
Loads; (4) updated the Large Load Customer definition to clearly define roles and responsibilities; 
(5) expanded process detail across several Tariff sections, including applicability screening, pre-
MTEP/EPR timing, and transitional provisions for inflight projects; and (6) clarified that Tariff 
applicability for the ramp, PMU, and ride-through requirements align with NERC’s emerging 
definition of Computational Loads and NERC’s Load Modeling Task Force technical discussions.  
MISO additionally revised the Large Load definition by removing the Large Load Campus 
construct in response to stakeholder feedback.  In addition, MISO published a technical 
compendium outlining the technical details of the proposal that will establish the basis of the 
Business Practice Manual (“BPM”) for Large Load. 
 
 
At the June 29, 2026, LLWG, MISO reviewed Tariff redlines for the Large Load definition 
and Large Load Interconnection Reliability Requirements based on stakeholder feedback.  
Stakeholder feedback significantly influenced the revised Tariff language, specifically around 
applicability, transition provisions, and requirement specific language.  MISO additionally 
described how its proposed framework is consistent with the Commission’s Show Cause Order 
and noted that the framework is also in line with the emerging NERC guidance and broader 
industry practices.  Furthermore, MISO described how its interconnection framework relies on the 
Tariff to set requirements and its BPM to guide consistent implementation, noting that it is 
targeting Large Load BPM development to take place from June to September 2026.  MISO 
requested stakeholder feedback on the Tariff updates.  
 
MISO separately presented on Large Load Telemetry and PMU Requirements, with the 
purpose of establishing SCADA telemetry requirements for Large Loads, and PMU requirements 
for Computational Loads to provide situational awareness and support system reliability across the 
MISO footprint.  Specifically, MISO will require real-time SCADA telemetry from Large Loads 
via ICCP to support real-time monitoring and analysis, and real-time SCADA telemetry from 
generation behind same POI as Large Load will also be required for real-time monitoring and 
optimal market dispatch; generator telemetry shall not be netted with load.  Furthermore, MISO

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 29 
 
 
will require PMU or similar device at the Large Load with computational load to support dynamic 
monitoring in real-time.  MISO requested stakeholder feedback on The Large Load Telemetry And 
PMU Requirements.  
 
MISO also presented on Large Load Operation Forecast Requirements, proposing that 
Large Loads submit short-term forecasts to reliably manage their variability.  In particular, MISO 
proposed Large Load forecast submission at the CP node level, on hourly and 5-minute cadences 
aligned with commitment and dispatch and defined forecast error measurement and submission 
monitoring, noting that it is considering mechanisms to incentivize accurate submissions.  MISO 
highlighted that NERC has called for short-term forecast submissions from Large Loads, that SPP 
requires them today, and that CAISO has identified the same visibility gap.  MISO requested 
stakeholder feedback on this topic.  
 
At the July 15, 2026, PAC, MISO informed stakeholders that the Steering Committee 
approved reassignment of the Large Load definition to the LLWG.  At the July 16, 2026 LLWG, 
MISO noted in its liaison report that there is a transition plan to manage active projects, explaining 
that a key consideration has been ensuring reliability while avoiding disruption to loads at a late 
stage of development.  MISO noted that this consideration is reflected in the Commission’s Show 
Cause Order and that it has received stakeholder feedback indicating that its current proposal does 
not achieve this directive.  Therefore, MISO revised its approach to apply full requirements only 
to loads that MISO has not yet approved through its planning processes, and to apply visibility 
requirements to a broader set of Large Loads.   
 
MISO also discussed the Large Load BPM framework and development, focusing on 
changes for interconnection and operational reliability requirements.  MISO proposed a “hub-and-
spoke” BPM framework consisting of a new Large Load BPM, the “hub”,  supported by updates 
to existing BPMs and manuals, the “spokes.”  MISO requested stakeholder feedback on the Large 
Load BPM framework.  
 
At the July 27, 2026, LLWG, MISO reviewed Tariff redlines for the Large Load definition 
and Large Load Interconnection Reliability Requirements based on stakeholder feedback.  MISO 
noted that its BPM development timeline has been extended to December 2026.  MISO also 
provided updates to its Technical Compendium and requested stakeholder feedback on its Tariff 
updates. 
  
At the August 12, 2026, LLWG, MISO reviewed the informal stakeholder feedback on the 
reliability requirement updates provided at the July 27, 2026 LLWG.  MISO discussed the 
additional refinements it made to its proposal based on informal stakeholder feedback.  MISO also 
held an LLWG meeting on August 27, 2026.  For this meeting, MISO posted final Tariff language 
for the IRR Proposal, and discussed two clarifying updates included in the Tariff language related 
to an explicit statement that Transmission Owners are required to install PMUs, at the Transmission 
Customer’s expense, and clarifications to MISO’s Ride-Through requirements.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 30 
 
 
 
As described above, throughout the stakeholder engagement period, MSO has solicited 
feedback from stakeholders and provided written and verbal responses to that feedback.  MISO’s 
stakeholder process has contributed to substantive design changes in MISO’s filing and the 
collaborative process with stakeholders resulted in a comprehensive proposal for addressing Large 
Loads in the MISO footprint.  MISO appreciates the willingness of all its stakeholders and state 
regulators to review and comment on this final proposal, which MISO believes reasonably 
accommodates concerns raised by stakeholders. 
 
 
In addition to the stakeholder meetings, MISO’s external affairs and Large Load teams 
have met with individual stakeholders and RERRAs to inform them about MISO’s proposal and 
answer questions.  MISO is aware that this is a pressing topic in the MISO footprint and commits 
to working with stakeholders and RERRAs to address any questions that may arise. 
 
VI. 
DOCUMENTS SUBMITTED IN THIS FILING 
In addition to this Transmittal Letter, this submission includes: 
Tab A – Redline Tariff;53, 
Tab B – Clean Tariff; and 
Tab C – Prepared Direct Testimony of Beibei Li. 
VII. 
EFFECTIVE DATE AND REQUEST FOR WAIVER 
MISO requests an effective date of December 4, 2026, which is not less than sixty (60) 
days nor more than one-hundred and twenty (120) days from the date of this filing.  As discussed 
above and in the supporting testimony of Ms. Li, December 4, 2026, is the date after which the 
MISO Board is expected to approve the MTEP 2026 projects and aligns with the IRR transition 
provisions described above. 
MISO also requests waiver of Section 35.13 of the Commission’s regulations, 18 C.F.R. § 
35.13 (2026), to the extent applicable to this filing, and requests waiver of any other applicable 
requirement of 18 C.F.R. Part 35 for which waiver is not specifically requested, if necessary, in 
order to permit Commission acceptance of this filing. 
 
53  Language currently pending before the Commission in the following, unrelated dockets is highlighted in yellow: 
Docket No.  ER26-2974-000.  MISO requests that the Commission treat such highlighted language as subject to 
the outcome of that pending proceeding.  MISO commits to file any revisions to this highlighted language as 
necessary to comply with any Commission orders in that proceeding.   
 
In addition, MISO has not included language that has future effective dates of 9/1/2027 in Docket No. ER25-
1886-000 and 6/1/2029 in Docket No. ER22-1640-003.  If needed, MISO commits to file any revisions to comply 
with any Commission orders in these proceedings and MISO commits to make subsequent filings with the 
Commission to reflect the most up-to-date version of the then-current Tariff provisions prior to the effective dates 
of the language.

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 31 
 
 
 
VIII. 
COMMUNICATIONS 
MISO respectfully requests waiver of Rule 203(b)(3) of the Commission’s Rules of 
Practice and Procedure, 18 C.F.R. § 385.203(b)(3) (2026), to the extent necessary to permit the 
designation of more than two persons for service on behalf of MISO in this proceeding and requests 
all communications related to this filing be directed to: 
Michael Kessler  
Managing Assistant General Counsel 
Midcontinent Independent System   
Operator, Inc. 
720 City Center Drive  
Carmel, Indiana 46032  
Telephone: (317) 753-9434 
mkessler@misoenergy.org 
 
James C. Holsclaw 
Calfee, Halter & Griswold LLP 
3900 Salesforce Tower 
111 Monument Circle 
Indianapolis, Indiana 46204 
Telephone: (317) 308-4266 
jholsclaw@calfee.com  
 
IX. 
NOTICE AND SERVICE 
MISO has served a copy of this filing electronically, including attachments, upon all Tariff 
customers, MISO Members, Member representatives of Transmission Owners and non-
Transmission Owners, as well as all state commissions within the MISO Region and the 
Organization of MISO States.  The filing has been posted electronically on MISO’s website at 
https://www.misoenergy.org/legal/ferc-filings/ for other interested parties in this matter. 
X. 
CONCLUSION 
For all of the foregoing reasons, MISO respectfully requests that the Commission accept 
this filing and grant waiver of any Commission regulations the Commission deems in order for the 
Commission to accept it as proposed. 
Respectfully submitted, 
 
/s/ Michael Kessler 
Michael Kessler  
Managing Assistant General Counsel 
Midcontinent Independent System   
Operator, Inc. 
720 City Center Drive  
Carmel, Indiana 46032  
Telephone: (317) 753-9434 
mkessler@misoenergy.org 
 
James C. Holsclaw

The Honorable Debbie-Anne Reese 
August 28, 2026 
Page 32 
 
 
Calfee, Halter & Griswold LLP 
3900 Salesforce Tower 
111 Monument Circle 
Indianapolis, Indiana 46204 
Telephone: (317) 308-4266 
jholsclaw@calfee.com   
 
Attorneys for the Midcontinent Independent 
System Operator, Inc. 
Attachments