ER26-3650-000 · 2026-09-18 · CENTRAL MINNESOTA MUNICIPAL POWER AGENCYIndiana Municipal Power AgencyMissouri Joint Municipal Electric Utility Commission ,WPPI Energy ,

Motion to Intervene and Comments of Central Municipal Power Agency/Services et al. re Midcontinent Independent System Operator, Inc.'s 08/28/2026 filing

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UNITED STATES OF AMERICA 
BEFORE THE 
FEDERAL ENERGY REGULATORY COMMISSION 
Midcontinent Independent System 
Operator, Inc. 
Docket No.  ER26-3650-000 
 
MOTION TO INTERVENE AND COMMENTS OF 
CENTRAL MUNICIPAL POWER 
AGENCY/SERVICES, INDIANA MUNICIPAL 
POWER AGENCY, MISSOURI JOINT MUNICIPAL 
ELECTRIC UTILITY COMMISSION, AND WPPI 
ENERGY 
Pursuant to Rules 212 and 214 of the Federal Energy Regulatory Commission’s 
(the “Commission”) Rules of Practice and Procedure,1 and the Commission’s August 31, 
2026 Combined Notice of Filings #1,2 Central Municipal Power Agency/Services 
(“CMPAS”), Indiana Municipal Power Agency (“IMPA”), Missouri Joint Municipal 
Electric Utility Commission (“MJMEUC”), and WPPI Energy (“WPPI”) (collectively, 
“Midwest TDUs”) each moves to intervene in this proceeding and together comment on 
Midcontinent Independent System Operator, Inc.’s (“MISO”) August 28, 2026 filing to 
revise its Open Access Transmission, Energy, and Operating Reserve Markets Tariff 
(“Tariff”) to implement Interconnection Reliability Requirements for Large Loads.3  
Midwest TDUs recognize the reliability challenges posed by the influx of new 
large loads seeking to interconnect to the MISO Transmission System4 and appreciate 
 
1 18 C.F.R. §§ 385.212 and 385.214. 
2 eLibrary No. 20260831-3080. 
3 MISO, Interconnection Reliability Requirements for Large Loads (Aug. 28, 2026), eLibrary 
No. 20260828-5278 (“MISO Filing”). 
4 Unless otherwise noted, capitalized terms in these comments refer to the terms as defined in the MISO 
Tariff, including terms that would be defined under the Tariff revisions MISO has filed in this proceeding.

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MISO taking swift action to address these challenges. At the same time, addressing these 
complex challenges must be done in a way consistent with the Show Cause Order the 
Commission issued to MISO5 and that avoids unintended adverse consequences. 
Midwest TDUs therefore seek clarification on two issues:  
• That MISO’s proposed Interconnection Reliability Requirements for 
Large Loads apply to those Large Loads interconnected to the MISO 
Transmission System (and not to loads interconnected at to the distribution 
system). This scope of applicability is consistent with MISO’s explanation 
of its filing and the Commission’s Show Cause Order, but Midwest TDUs 
seek clarification to avoid any potential confusion on this key point.  
• That implementation of these requirements will not unduly burden 
Transmission Customers. Midwest TDUs appreciate that MISO proposes 
to allow Transmission Customers to demonstrate their ability to comply 
with these requirements through agreements with a Large Load—as 
ultimately Large Loads create the reliability risks at issue, and those risks 
can only be avoided with the cooperation of Large Loads. But additional 
clarity is needed to ensure that Transmission Customers can rely on these 
agreements to avoid undue burdens. In addition, MISO should confirm 
that it will play a central role in communication and educating Large 
Loads about these requirements, because otherwise important details 
needed to ensure reliability may get lost in translation, frustrating the 
intended reliability purpose.  
To the extent that MISO does not clarify these issues on its own, the Commission 
should direct it to do so in a deficiency letter. And if MISO’s proposed Tariff language 
does not clearly reflect these clarifications, the Commission should order MISO to make 
further revisions to the Tariff language to do so.6  
 
5 Midcontinent Indep. Sys. Operator, Inc., 195 FERC ¶ 61,212 (2026) (“MISO Show Cause Order”).  
6 Because addressing these discrete issues would not result in an “entirely different rate design” (or even 
change the substance of the requirements posed by MISO) the Commission has authority to require MISO 
to address them without rejecting the filing. Cal. Indep. Sys. Operator Corp., 178 FERC ¶ 61,182, P 30 
nn.43-44 (2022) (quoting NRG Power Mktg., LLC v. FERC, 862 F.3d 108, 115 (D.C. Cir. 2017)); see also 
El Paso Nat. Gas Co. v. FERC, 966 F.3d 842, 863 (D.C. Cir. 2020) (explaining that under an analogous 
provision of the Natural Gas Act “[i]f the rate imposed by FERC ‘differs significantly’ from the rate 
proposed by the pipeline, it can no longer be attributed to the pipeline or qualify for Section 4 treatment,”

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I. 
MOTION TO INTERVENE 
Each Midwest TDU (described in Attachment A hereto) moves to intervene with 
full rights as parties to this proceeding. As market participants, load-serving entities, and 
customers under MISO’s Tariff, Midwest TDUs will be directly affected by MISO’s 
proposed Tariff revisions. They each have clear and substantial interests in this 
proceeding that cannot be represented by any other party, and their participation would be 
in the public interest. Midwest TDUs should therefore each be granted intervention. 
Communications regarding this proceeding should be directed to the following:7 
Cynthia S. Bogorad 
Jeffrey M. Bayne 
SPIEGEL & MCDIARMID LLP 
1818 N Street, NW 
8th Floor 
Washington, DC 20036 
Phone: (202) 879-4000 (Phone)  
Fax: (202) 393-2866 (Fax) 
Email: cynthia.bogorad@spiegelmcd.com  
 
jeffrey.bayne@spiegelmcd.com 
 
CMPAS: 
Jay Anderson, Chief Executive Officer 
CENTRAL MUNICIPAL POWER 
AGENCY/SERVICES 
7550 Corporate Way 
Suite 100 
Eden Prairie, MN 55344 
Phone: (888) 970-8267 
Email:  jaya@cmpas.org 
 
 
 
but “[u]nder this Court’s precedents, FERC can alter a proposed rate and remain in a Section 4 proceeding 
as long as its change represents ‘at least partial approval of the change’ for which the pipeline itself 
petitioned” (emphasis added) (first quoting W. Res., Inc. v. FERC, 9 F.3d 1568, 1579 (D.C. Cir. 1993); and 
then quoting Pub. Serv. Comm’n of N.Y. v. FERC, 642 F.2d 1335, 1345 (D.C. Cir. 1980))). 
7 Midwest TDUs request waiver of Rule 203(b)(3) of the Commission’s Rules of Practice and Procedure, 
18 C.F.R. § 385.203(b)(3), so as to permit more than two entries on the official service list in order to 
enable Midwest TDUs to promptly receive all communications in the proceeding.

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IMPA: 
Peter J. Prettyman 
Indiana Municipal Power Agency 
11610 North College Avenue  
Carmel, IN  46032  
Phone: (317) 575-3870 
Fax: (317) 575-3372 
Email: pprettyman@impa.com 
 
 
WPPI: 
Tom Hanrahan, General Counsel 
WPPI ENERGY 
1425 Corporate Center Drive 
Sun Prairie, WI 53590-9109 
Phone: (608) 834-4556 
Email: thanrahan@wppienergy.org 
 
MJMEUC: 
Steve Stodden, President and CEO 
MISSOURI JOINT MUNICIPAL ELECTRIC 
UTILITY COMMISSION  
2200 Maguire Blvd. 
Columbia, MO 65201 
Phone: (573) 445-3279 
Fax: (573) 445-0680 
Email: sstodden@mpua.org 
 
Terry M. Jarrett, General Counsel 
MISSOURI JOINT MUNICIPAL ELECTRIC 
UTILITY COMMISSION  
2200 Maguire Blvd. 
Columbia, MO 65201 
Phone: 573-445-3279 
Fax: (573) 445-0680 
Email: tjarrett@mpua.org 
 
 
 
II. 
COMMENTS 
A. 
Midwest TDUs seek confirmation that the proposed requirements 
apply only to those Large Loads directly connected to the MISO 
Transmission System.  
MISO should confirm that its proposed requirements apply only to those Large 
Loads directly connected to the MISO Transmission System. To the extent MISO’s 
proposed Tariff language does not clearly impose this limit, the Commission should 
direct MISO to revise its proposed Tariff language to do so. 
MISO’s filing appears to impose the proposed Large Loads Interconnection 
Reliability Requirements on only those Large Loads that are interconnected to the MISO 
Transmission System, and there is no indication that MISO intends to extend these 
requirements to any loads interconnected to distribution facilities. There is no mention of 
distribution-level interconnection in MISO’s transmittal letter, proposed Tariff revisions, 
or supporting testimony.

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Indeed, MISO witness Beibei Li describes the scope of MISO’s filing as 
“propos[ing] reliability requirements and a reliability-based framework applicable to 
Transmission Customers taking Transmission Service on behalf of Large Load 
interconnected to the MISO Transmission System.”8 And although MISO’s proposed 
definition of Large Load does not expressly refer to interconnections to the MISO 
Transmission System,9 other Tariff language in MISO’s filing does explicitly refer to 
interconnections to the Transmission System. For example, “Large Load Equipment” is 
defined as “[a]ny 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.”10 And the 
Large Load Ride-Through Requirement states that it is designed to “ensur[e] that the 
Computational Load remains 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.”11 
In addition, MISO’s filing is in response to the Commission’s MISO Show Cause 
Order,12 which specifically focused on large load interconnections to the transmission 
 
8 MISO Filing, Tab C, Prepared Direct Testimony of Beibei Li Senior Manager of Strategic Assessment at 
15 (“Li Test.”) (emphasis added).  
9 The MISO Tariff defines the “Transmission System” as “[t]he transmission facilities owned or controlled 
by Transmission Owners that have conveyed functional control to the Transmission Provider, and are used 
to provide Transmission Service under Module B of this Tariff…,” and the Tariff specifically states that 
Distribution Facilities are “not part of the Transmission System.” MISO Tariff § 1.T. (Note, the language 
quoted above is only part of the definition of Transmission System, not the complete definition.) 
10 MISO Filing, Tab A, Redlined Tariff § 1.L (“Redlined Tariff”).  
11 Id. § 37A.6.  
12 MISO Filing, Transmittal Letter at 1 (“Transmittal”) (“The [Interconnection Reliability Requirements] 
Proposal is responsive to several of the concerns raised by the Commission in the Order Instituting

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system. For example, the Commission’s suggested “reasonable” definition of a large load 
is one that “interconnects to the transmission system at a voltage level greater than 69 
kV,”13 and the MISO Show Cause Order repeatedly refers to the interconnection of large 
loads to the transmission system.14 
Consistent with the MISO Show Cause Order, MISO’s intent appears to be that 
these requirements are specifically for Large Loads interconnected to the MISO 
Transmission System. MISO’s proposed definition of Large Load, however, lacks the 
explicit language suggested in the Show Cause Order regarding transmission-level 
interconnection. MISO defines a Large Load as one “located at a single substation behind 
one or more Point(s) of Withdrawal from the Transmission System,”15 with “Point(s) of 
Withdrawal” defined as “[t]he point(s) where a non-transmission facility that is used to 
 
Proceeding Under Section 206 of the Federal Power Act4 in Docket No. EL26-70-000 . . . .” (footnote 
omitted)).  
13 MISO Show Cause Order, P 58 (emphasis added). The MISO Show Cause Order similar indicates that it 
would be “reasonable” to define co-located loads “as a configuration that refers to end-use customer load 
that is physically connected to the facilities of an existing or planned generating facility on the generator 
interconnection customer’s side of the point of interconnection to the RTO/ISO’s transmission system.” Id. 
P 89 (emphasis added).   
14 See, e.g., id. P 1 (explaining that “stakeholders have expressed concerns that large loads are not 
efficiently and appropriately integrated onto the transmission system”); id. P 12 (“There is also broad 
support for rules that help to ensure that other transmission customers are not unfairly burdened with 
additional costs or reliability impacts as large and co-located loads interconnect to the transmission 
system.”); P 42 (“At the outset, we clarify the principles relating to the Commission’s jurisdiction over the 
matters relevant to the integration of large loads onto the transmission system and the impacts of large 
loads on the transmission system.”); P 45 (“As applied to large load additions to the transmission system, 
these principles mean that the Commission has exclusive jurisdiction over the rates, terms, and  conditions 
of interstate transmission service to Eligible Customers on behalf of large loads connecting to the 
transmission system, and the practices directly affecting the provision of such interstate transmission of 
electricity.”); P 123 (“We also understand that large loads and Eligible Customers taking transmission 
service on behalf of large loads are negotiating, entering into, and/or have executed various agreements 
related to interconnecting to the transmission system and/or the provision of transmission service.”). 
15 Redline Tariff § 1.L (proposed definition of Large Load) (emphasis added).

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withdraw Energy from the Transmission System to serve Load connects to the 
Transmission System.”16  
While MISO’s reference to Point(s) of Withdrawal from the Transmission System 
strongly suggests loads interconnected at the distribution level are not covered by the 
definition of Large Load, the term “behind” could potentially be read broadly to 
encompass anything behind such Point(s) of Withdrawal (such as also behind a 
distribution transformer)—not just what is directly behind such points and connected at 
transmission voltages. There is additional potential ambiguity because the term “non-
transmission facility” used in the definition of Point(s) of Withdrawal is not defined.17  
Midwest TDUs believe that MISO’s intent to limit Large Loads to those 
connected to the MISO Transmission System should be clear for the reasons stated 
above. But to avoid any potential confusion, MISO should confirm the scope of its 
Interconnection Reliability Requirements for Large Loads. To the extent that MISO’s 
proposed Tariff language is not clear on this point, the Commission should direct MISO 
to revise the definition of Large Load to include more explicit language on the 
requirement that Large Loads are those directly interconnected to the MISO 
Transmission System. 
To the extent that MISO disagrees and argues that its new requirements should 
apply to loads interconnected to the distribution system (i.e., behind the transmission-to-
 
16 Id. § 1.P (proposed definition of Point(s) of Withdrawal).  
17 Although this term is undefined, Midwest TDUs believe it to be referring to facilities used to 
interconnect the large load to the MISO Transmission System (consistent with the proposed definition of 
Large Load Equipment), not a limitless term that could apply to any facility that is not considered 
transmission.

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distribution substation), the Commission should find that MISO has not justified that 
scope as just and reasonable and require MISO to revise its filing to apply only to Large 
Loads interconnected to the MISO Transmission System. Nothing in MISO’s filing 
addresses distribution-level interconnections, much less satisfies MISO’s burden under 
Federal Power Act (“FPA”) section 20518 to demonstrate the justness and reasonableness 
of encompassing distribution-level interconnections.  
Moreover, imposing requirements on distribution-level interconnections would go 
far beyond the careful and deliberate approach taken in the Commission’s Show Cause 
Order—particularly with respect to jurisdictional issues.19 Similarly, while MISO 
supports its filing by citing to reliability concerns raised by North American Electric 
Reliability Corporation (“NERC”),20 extending MISO’s proposed reliability requirements 
to Large Loads connected at the distribution level would be inconsistent with actions 
NERC itself is taking. In response to the Commission’s recent directive that NERC 
propose reliability standards and propose registry criteria to “address reliability risks to 
the Bulk-Power System associated with the integration of computational loads,”21 NERC 
is focusing on large computational loads interconnected to the transmission system. For 
 
18 16 U.S.C. § 824d.  
19 See, e.g., MISO Show Cause Order, P 43 (“As discussed below, however, certain aspects of the process 
for integrating large loads onto the transmission system fall squarely within the Commission’s exclusive 
jurisdiction. Specifically, we find that it is within the Commission’s exclusive authority to ensure that 
transmission provider and/or transmission owner tariffs include sufficiently clear and consistent provisions 
governing how transmission service to Eligible Customers on behalf of large loads interconnecting to the 
transmission system will be studied . . . .” (emphasis added)); id. P 44 (“As part of its transmission 
authority, the Commission has exercised jurisdiction over the terms of certain interconnections to the 
transmission system as an element of transmission service, including the interconnection of wholesale load 
to the transmission system.” (footnote omitted) (emphasis added)).  
20 Transmittal at 7. 
21 Reliability Standard(s) Pertaining to Computational Load Integration, 196 FERC ¶ 61,031, P 1 (2026).

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example, NERC’s currently proposed revised draft registry criteria for Computational 
Load Owner and Operator, as posted on August 19, 2026 for industry comment (due 
September 18, 2026), are limited to such loads of at least 50 MW connected to 
transmission facilities of at least 100 kV.22 The associated Updated Technical Reasoning, 
also posted on August 19, describes the technical basis and analyses supporting these 
thresholds.23 
In short, both the legal and factual basis of MISO’s filing are targeted toward 
large loads interconnected to Commission-jurisdictional transmission facilities. MISO’s 
proposed Tariff language should match that scope.  
B. 
MISO’s new requirements must be implemented in a way that 
does not unduly burden Transmission Customers and advances 
their reliability purpose. 
Although MISO refers to its newly proposed reliability requirements as “Large 
Load Reliability Requirements,” MISO proposes to make “[t]he Transmission Customer 
taking Transmission Service on behalf of a Large Load . . . responsible for complying 
 
22 NERC, Draft Rules of Procedure Appendix 5B, Statement of Compliance Registry Criteria Revision 9 
§ III(c) Computational Load Owner or Operator (Aug. 19, 2026), https://www.nerc.com/globalassets/who-
we-are/rules-of-procedure/proposed/appendix-5b-clean---august-2026-posting.pdf:  
III.c.1 Computational Load Owner of a Computational Load Site with a total connected 
Load greater than or equal to 50 MW that is supplied through electrical equipment 
connected at a voltage level greater than or equal to 100 kV from one or more points of 
connection. 
III.c.2 Computational Load Operator of a Computational Load Site with a total connected 
Load greater than or equal to 50 MW that is supplied through electrical equipment 
connected at a voltage level greater than or equal to 100 kV from one or more points of 
connection. 
23 NERC, Technical Reasoning Update, Proposed Computational Load Owner and Computational Load 
Operator at 3-4 (Aug. 19, 2026), https://www.nerc.com/globalassets/who-we-are/rules-of-
procedure/proposed/august-posting-technical-reasoning.pdf.

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with each of the requirements.”24 In other words, the Transmission Customer—not the 
Large Load—would be responsible for the proposed visibility requirements, phasor 
measurement unit requirements, ramp requirements, and ride-through requirements. 
These requirements would impose significant burdens on Transmission Customers, 
particularly smaller municipal utilities, if they are forced to be the middlemen between 
MISO and the Large Loads that are best positioned to implement the proposed 
requirements to achieve their reliability purposes.  
For example, while direct implementation of the proposed Large Load 
requirements may pose challenges for all load-serving entities, requiring small utilities 
that serve Large Loads to add the necessary technology and infrastructure needed to 
directly meet MISO’s proposed Large Load requirements (including the additional 
requirements applicable to Computational Loads) would impose a disproportionate 
financial and administrative burden. Smaller utilities are unable to spread the significant 
costs and personnel needed to perform these specialized tasks in a rapidly evolving 
terrain. Thus, requiring small Transmission Customers to directly perform the primary 
role in complying with the proposed Large Load reliability requirements would impose a 
particularly heavy and undue burden on municipal and consumer-owned electric systems 
and their often rural customers.  
Midwest TDUs are particularly concerned with excessive burdens on 
Transmission Customers given that, as MISO’s filing itself makes clear, the reliability 
 
24 Redline Tariff § 37A(I) (emphasis added). See Li Test. at 17 (explaining the definition of the term 
“Transmission Customer,” which “include[s] customers receiving Transmission Service under Module B of 
[the MISO] Tariff”).

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risks at issue are those posed by Large Loads themselves—not the Transmission 
Customer. MISO explains that “the increasing size, concentration, and changing 
characteristics of Large Loads create a need for greater consistency in the information, 
visibility, and performance expectation necessary to reliably plan and operate the 
Transmission System.”25 MISO also emphasizes “the increased operational risk 
Computational Loads place on the Transmission System.”26 In explaining why MISO 
proposes to make the Transmission Customer responsible for compliance with these 
requirements, MISO does not claim that Transmission Customers are causing reliability 
risks; rather, it states that the “ultimate owner of a Large Load may not participate 
directly in MISO’s markets or otherwise have contractual privity to MISO.”27 
Midwest TDUs do not oppose, per se, requiring Transmission Customers to be 
responsible for compliance with these new requirements based on privity concerns. But 
to be just and reasonable, and not unduly discriminatory or preferential, compliance 
responsibility for the new requirements must be implemented in a manner that does not 
impose undue burdens on Transmission Customers, especially small utilities, for actions 
taken by the Large Loads they serve, and that facilitates achievement of MISO’s stated 
objective of ensuring grid reliability.   
MISO’s filing includes some language to reasonably limit the burden on 
Transmission Customers, but additional clarity is needed. Significantly, MISO’s 
proposed Tariff revisions expressly permit a Transmission Customer to demonstrate its 
 
25 Li Test. at 7 (emphasis added). 
26 Id. at 17.  
27 Id. at 18.

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ability to effectuate compliance with these requirements with “applicable agreement(s), if 
any, between the Transmission Customer and the entity or entities that own, operate or 
use the Large Load.”28 This language appropriately recognizes that compliance with 
these requirements ultimately depends on actions taken by the Large Load itself.  
Midwest TDUs support this provision allowing Transmission Customers to 
demonstrate compliance through agreements with the Large Loads. Because Large Loads 
are best positioned to ensure compliance with these new requirements, it is critical that 
Transmission Customers can enter into agreements that assign Large Loads the primary 
role for actually complying with the new requirements. But to ensure that Transmission 
Customers can rely on such agreements with Large Loads to ensure compliance without 
undue burdens, MISO should confirm or clarify the following issues. To the extent MISO 
does do so on its own, the Commission should issue a deficiency letter asking MISO to 
address these issues and require revisions to the Tariff language consistent with the points 
below. 
First, MISO should confirm that it will accept agreements that assign Large 
Loads the duty to comply with one or more of these new requirements as a sufficient 
demonstration of a Transmission Customers’ ability to effectuate compliance. Such 
confirmation will clarify the intent behind the language in proposed section 37A(I) 
quoted above and the types of agreements that will be acceptable for this purpose.29 
 
28 Redline Tariff § 37A(I). 
29 It may be beneficial for MISO to develop a standardized means for Transmission Customers to indicate 
that they have assigned compliance roles to a Large Load, so that this provision can be efficiently and 
consistently implemented. Midwest TDUs encourage MISO to work with stakeholders to do so.

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Second, MISO should clarify the full scope of potential consequences for non-
compliance with these new requirements, particularly for Transmission Customers that 
have entered into agreements with Large Loads to effectuate compliance. Proposed 
section 37A(I) states that “[f]ailure to comply with the requirements established in this 
Section 37A 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.”30 It is appropriate for the consequences for non-compliance to be tailored to 
address and prevent the reliability risks posed by Large Loads. Indeed, that should be the 
guiding principle for implementing these requirements. In contrast, it would be 
inappropriate to impose additional consequences or other unduly punitive penalties (such 
as financial penalties) on the Transmission Customer if these requirements are not met by 
the Large Load assigned responsibility for complying with these requirements under an 
agreement.  
Accordingly, MISO should clarify that the scope of “other remedial action(s)” is 
limited to actions that address the reliability impacts caused by Large Loads assigned 
compliance responsibility under their agreement with the Transmission Customer (rather 
than punitive measures against the Transmission Customer). Thus, the remedial actions 
should be targeted to measures that impact the Large Load that is in the best position to 
effectuate compliance. In addition, MISO should confirm that this language establishes 
the exclusive list of consequences for a Transmission Customer’s failure to comply with 
 
30 Id.

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the Interconnection Reliability Requirements for Large Loads where the Transmission 
Customer has by contract assigned the primary compliance role to the Large Load best 
positioned to perform that role. Doing so will ensure that the focus in the event of non-
compliance is on ensuring reliability, not penalizing Transmission Customers for actions 
beyond their reasonable control.  
Third, where a Transmission Customer demonstrates its ability to effectuate 
compliance with these requirements through an agreement with a Large Load, MISO 
should cooperate to ensure that compliance can be accomplished in an efficient manner 
consistent with such an agreement. For example, where appropriate and consistent with 
the terms of the agreement between the Large Load and Transmission Customer, MISO 
should accept information provided directly by the Large Load to MISO and the 
Transmission Customer, rather than rigidly requiring all information to pass through the 
Transmission Customer (or its equipment) as a middleman.  
Fourth, MISO should also provide educational and ongoing support to Large 
Loads themselves to ensure that they fully understand these new requirements. Although 
MISO’s proposed Tariff language makes the Transmission Customer responsible for 
compliance with these requirements, MISO cannot ignore that it is the actions taken by 
the Large Loads themselves that are the source of the reliability risks that need to be 
addressed. MISO has developed these new requirements to protect the MISO 
Transmission System against the impact of new Large Load interconnections, and MISO 
should play a central role in making sure that Large Loads fully comprehend these 
requirements and are well positioned to act consistently with them.

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It would not be just and reasonable for MISO to avoid any direct interactions with 
these Large Loads and instead solely rely on Transmission Customers to communicate 
these requirements to the Large Load to which responsibility is assigned by agreement. 
MISO, which developed these requirements for the stated purpose of protecting the 
Transmission System from reliability risks posed by Large Loads, should not by limit 
communications about these requirements to a game of telephone where all information 
must be conveyed through the Transmission Customer.31 Doing so could risk critical 
details getting lost in translation, undermining the reliability protection these 
requirements are meant to provide. The support MISO provides Transmission Customers 
and other stakeholders—such as service representatives, the MISO Help Center, and 
Customer and System Operator Training—should also be made directly available to 
Large Loads to facilitate compliance with these requirements, as Large Loads are best 
positioned to address reliability risks upon receipt of MISO’s guidance. 
 
31 A standardized means for Transmission Customers to indicate that they have assigned compliance roles 
to a Large Load, as noted above in footnote 29, would also allow MISO to more easily and accurately 
identify the particular Large Loads that have agreed to play a primary role in ensuring compliance with 
these requirements.

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CONCLUSION 
For the reasons discussed above, the Commission should (1) grant CMPAS, 
IMPA, MJMEUC, and WPPI intervention in this proceeding; and (2) ensure that the 
issues above are adequately clarified by MISO and order further Tariff revisions to the 
extent that MISO’s proposed language is not clear on these issues.  
 
Respectfully submitted, 
/s/ Cynthia S. Bogorad  
Cynthia S. Bogorad 
Jeffrey M. Bayne 
Attorneys for Midwest TDUs 
Law Offices of: 
Spiegel & McDiarmid LLP 
1818 N Street, NW 
8th Floor 
Washington, DC 20036 
(202) 879-4000 
September 18, 2026

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ATTACHMENT A

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A-1 
ATTACHMENT A: DESCRIPTION OF MIDWEST TDUS 
Central Minnesota Municipal Power Agency d/b/a Central Municipal Power 
Agency/Services (“CMPAS”) is a public power joint action agency organized under 
Minnesota law. CMPAS operates as a project-oriented agency. CMPAS and certain of its 
members own and operate transmission assets which have been turned over to the 
functional control of MISO. 
The Indiana Municipal Power Agency (“IMPA”) is a body corporate and 
politic, and a political subdivision of the State of Indiana.  IMPA was created in 1980, 
under the provisions of Indiana Code § 8-1-2.2, by a group of municipalities for the 
purpose of jointly financing, developing, owning, and operating electric generation and 
transmission facilities which are appropriate to the current and projected electric power 
needs of such municipalities.  IMPA became an operating utility in 1983, when it began 
to sell electric power to its member utilities under power sales contracts.  IMPA’s 
members currently comprise 60 Indiana cities and towns and one Ohio Village. 
IMPA is a member of Midcontinent Independent System Operator, Inc. (MISO).  
IMPA has ownership interests in generation resources within MISO, including co-
ownership with Duke Energy Indiana and Wabash Valley Power Alliance in the Gibson 
Station Unit 5, ownership interest in the Prairie State Energy Campus, ownership interest 
in Trimble County Units 1 and 2, and ownership of natural gas combustion turbine 
peaking units.  IMPA, Duke Energy Indiana, and the Wabash Valley Power Alliance 
have entered into a joint ownership agreement of the Joint Transmission System (JTS) in

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Attachment A 
A-2 
 
Indiana.  Access to the JTS transmission facilities is administered by MISO pursuant to 
its tariff. 
The Missouri Joint Municipal Electric Utility Commission (“MJMEUC”) is a 
joint action agency and a body corporate and politic of the State of Missouri authorized 
by legislation to construct, operate and maintain jointly owned transmission and 
generation facilities for the production and transmission of electric power for its 
members, to purchase and sell electric power and energy, and to enter into agreements 
with any person for transmission of electric power.  It is organized on a statewide basis to 
promote efficient wheeling, pooling, generation, and transmission arrangements to meet 
the power and energy requirements of municipal utilities in the state.  MEC membership 
is comprised of 72 municipal utility members and 4 advisory members.  Together, 
MEC’s members serve some 347,000 retail customers, with a combined peak load of 
approximately 2,600 MW. 
Since January 1, 2000, pursuant to its authority under state law, MEC has been 
administering a power pool formed by some of MEC’s members.  The Missouri Public 
Energy Pool #1 (“MoPEP”) currently has 35 members, whose 2024 summer peak load 
was approximately 528 MW.  MoPEP is the full-requirements supplier for its members, 
and meets their capacity and energy requirements through generating and purchased-
power resources contributed by the pool members, and through additional resources 
arranged for by MoPEP.  MoPEP has pool loads and/or resources located within the 
transmission systems of several members of MISO and SPP.  In addition, as of June 1, 
2020, MEC administers, pursuant to its state law authority, a full-requirements power 
pool formed by two of MEC’s members (with a third taking supply starting in June 2025)

PDF page 20

Attachment A 
A-3 
 
with a 2024 summer peak load of 58 MW, titled the Southwest Missouri Public Energy 
Pool (“SWMPEP”). This pool was formed to collectively purchase power at wholesale 
costs to serve its members’ load. MEC has load in multi-owner transmission pricing 
zones in SPP. 
WPPI Energy (“WPPI”) is a municipal electric company formed pursuant to 
Wis. Stat. § 66.0825.  WPPI provides bulk power and other services to its 51 members 
(50 municipalities and one cooperative), each of which operates a distribution utility and 
sells electricity at retail to the residences, businesses, and industries in and around its 
municipality.  These members are located within the Wisconsin, Michigan, and/or Iowa 
service territories of four large investor-owned utilities: Northern States Power-
Wisconsin (Xcel Energy (“Xcel”)), WEC Energy Group (Wisconsin Electric Power 
Company (“WEPCO”) and Wisconsin Public Service Corp. (“WPS”)), Upper Peninsula 
Power Co., and Alliant Energy (Wisconsin Power & Light Co. (“WP&L”) and Interstate 
Power and Light Co.).  The bulk of WPPI’s load is on the American Transmission 
Company LLC (“ATCLLC”), Xcel, or ITC Midwest transmission systems, although 
some of WPPI’s resources are located in other transmission zones in MISO, as well as in 
PJM Interconnection, L.L.C.  WPPI supplies the bulk power and energy requirements of 
its members from generation resources owned by WPPI and through purchased power 
contracts. 
WPPI is a longstanding member of MISO, with both generation and load within 
the MISO footprint, and owns portions of transmission projects. WPPI also is a 
participating owner of ATCLLC, a MISO Transmission Owner which was formed 
pursuant to 1999 Wisconsin Act 9 with WPPI’s support.

PDF page 21

CERTIFICATE OF SERVICE 
I hereby certify that I have this day caused the foregoing document to be served 
upon each person designated on the official service list compiled by the Secretary in this 
proceeding. 
Dated on this 18th day of September, 2026. 
/s/ Jeffrey M. Bayne  
Jeffrey M. Bayne 
Law Offices of: 
 
Spiegel & McDiarmid LLP 
1818 N Street, NW 
8th Floor 
Washington, DC 20036 
(202) 879-4000