ER26-3650-000 · 2026-10-28 · Central Municipal Power Agency/ServicesMissouri Joint Municipal Electric Utility CommissionWPPI Energy ,Indiana Municipal Power Agency ,

Motion for Leave to Answer and Answer of Central Municipal Power Agency Services, et al. to Midcontinent Independent System Operator, Inc.’s 10/13/2026 Motion for Leave to Answer and Answer

UNITED STATES OF AMERICA 
BEFORE THE 
FEDERAL ENERGY REGULATORY COMMISSION 
Midcontinent Independent System 
Operator, Inc. 
Docket No.  ER26-3650-000 
 
MOTION FOR LEAVE TO ANSWER AND ANSWER 
OF MIDWEST TDUS  
Pursuant to Rules 212 and 213 of the Federal Energy Regulatory Commission’s 
(“FERC” or “Commission”) Rules of Practice and Procedure,1 Midwest TDUs2 
respectfully move for leave to answer and answer the October 13, 2026, Motion for 
Leave to Answer and Answer filed by the Midcontinent Independent System Operator, 
Inc. (“MISO”).3 MISO’s Answer responds to Midwest TDUs’ Comments,4 and protests 
by numerous other intervenors, of MISO’s original filing5 to revise its Open Access 
Transmission, Energy, and Operating Reserve Markets Tariff (“Tariff”) to implement 
Interconnection Reliability Requirements for certain large loads. 
Midwest TDUs’ Answer below explains that MISO’s Answer does not resolve the 
concerns identified in our original Comments. Specifically:  
 
1 18 C.F.R. §§ 385.212, 385.213. 
2 Midwest TDUs consist of Central Municipal Power Agency/Services (“CMPAS”), Indiana Municipal 
Power Agency (“IMPA”), Missouri Joint Municipal Electric Utility Commission (“MJMEUC”), and WPPI 
Energy (“WPPI”). 
3 Motion for Leave to Answer and Answer of the Midcontinent Independent System Operator, Inc. (Oct. 
13, 2026), eLibrary No. 20261013-5440 (“MISO Answer”). 
4 Motion to Intervene and Comments of Central Municipal Power Agency/Services, Indiana Municipal 
Power Agency, Missouri Joint Municipal Electric Utility Commission, and WPPI Energy (Sept. 18, 2026), 
eLibrary No. 20260918-5272 (“Midwest TDUs Comments”). 
5 MISO, Interconnection Reliability Requirements for Large Loads (Aug. 28, 2026), eLibrary No. 
20260828-5278 (“MISO Filing”).

- 2 - 
• Although MISO’s Answer confirms MISO’s intent not to impose its 
proposed Interconnection Reliability Requirements on distribution-
connected loads, it fails to show that this critical threshold issue is 
unambiguously addressed in the proposed Tariff language.  
• MISO’s Answer fails to provide additional clarity as to how it will 
effectuate a Transmission Customer’s agreement with a Large Load that 
assigns one or more compliance responsibilities to the Large Load. 
Midwest TDUs appreciate MISO’s confirmation that Transmission 
Customers may rely on such agreements to demonstrate compliance with 
the Interconnection Reliability Requirements, but more clarity is needed to 
ensure that they can do so in a manner that is efficient and not unduly 
burdensome.  
The Commission should therefore issue a deficiency letter directing MISO to 
address these issues and require revisions to the proposed Tariff language reflecting the 
requested clarifications.  
I. 
MOTION FOR LEAVE TO ANSWER 
The Commission’s Rules of Practice and Procedure prohibit answers to answers 
unless otherwise authorized by the Commission,6 but the Commission has authority to 
waive this prohibition for good cause.7 The Commission has found good cause to waive 
the general prohibition on answers to answers where, among other things, the answer 
would assist the Commission in its decision-making process.8 Midwest TDUs’ Answer to 
MISO’s Answer will aid the Commission’s understanding of the important issues 
presented by MISO’s Interconnection Reliability Requirements proposal. Midwest TDUs 
respectfully request that the Commission grant leave to submit the following Answer. 
 
6 18 C.F.R. § 385.213(a)(2). 
7 Id. § 385.101(e). 
8 See, e.g., Midcontinent Indep. Sys. Operator, Inc., 191 FERC ¶ 61,131, P 24 (2025) (accepting answers to 
answers “because they have provided information that assisted us in our decision-making process”).

- 3 - 
II. 
ANSWER 
A. 
Further clarity is needed to ensure that MISO’s proposed 
Interconnection Reliability Requirements are limited to 
Transmission System-connected Large Loads.  
Midwest TDUs appreciate MISO’s apparent confirmation that it intends for the 
proposed Interconnection Reliability Requirements to apply only “to Transmission 
Customers taking Transmission Service on behalf of Large Loads connected to the MISO 
Transmission System.”9 This straightforward statement of the applicability of these 
requirements is consistent with testimony that its Answer cites: “This filing proposes 
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.”10 The brief discussion of this critical threshold point in 
MISO’s Answer, however, fails to resolve the potential for ambiguity in the proposed 
Tariff language.  
As noted in our Comments at 6-7, MISO defines a Large Load as one “located at 
a single substation behind one or more Point(s) of Withdrawal from the Transmission 
System,”11 with “Point(s) of Withdrawal” defined as “[t]he 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.”12 MISO’s definition, unlike the one in 
the Commission’s Show Cause Order, does not specify that a Large Load “interconnects 
 
9 MISO Answer at 26 (emphasis added).  
10 MISO Filing, Tab C, Prepared Direct Testimony of Beibei Li, Senior Manager of Strategic Assessment, 
Testimony at 15(emphasis added), included in testimony pages referenced in MISO’s Answer at 27. See 
also Midwest TDUs Comments at 5 (summarizing similar references in MISO’s original filing).  
11 MISO Filing, Tab A, Redline Tariff § 1.L (proposed definition of Large Load).  
12 Id. § 1.P (proposed definition of Point(s) of Withdrawal).

- 4 - 
to the transmission system.”13 MISO’s Answer does not address the specific sources of 
confusion in its proposed Tariff language that Midwest TDUs identified in our 
Comments, such as how broadly “behind” the Point of Withdrawal from the 
Transmission System could extend without language specifying that a Large Load must 
interconnect to the transmission system.14 Instead, MISO states that the references to the 
Transmission System in its proposed Tariff language means that “the [Interconnection 
Reliability Requirements] Proposal does not create a free-standing MISO reliability 
regime for distribution-connected load that is not taking MISO Transmission Service.”15  
Unfortunately, MISO’s explanation underscores the need for further specificity in 
the proposed Tariff language. The relevant distinction for purposes of MISO’s Large 
Load definition is not whether the Transmission Customer is “taking MISO Transmission 
Service” on behalf of the load, since an Eligible Customer can take Transmission Service 
on behalf of load interconnected to either the MISO Transmission System or a 
distribution system.  
Rather, MISO’s Tariff language should explicitly define Large Loads as those that 
“interconnect[] to the transmission system,”16 which makes clear that the Interconnection 
Reliability Requirements do not apply to distribution-connected loads.17 These 
 
13 Midcontinent Indep. Sys. Operator, Inc., 195 FERC ¶ 61,212, P 58 (2026) (“MISO Show Cause Order”).    
14 See Midwest TDUs Comments at 6-7. 
15 MISO Answer at 27 (emphasis added).  
16 MISO Show Cause Order P 58.  
17 The Computational Load registry criteria discussed in Midwest TDUs’ Comments at 9 n.22 (quoting the 
proposed criteria which, among other things, require the load to be “connected at a voltage level greater 
than or equal to 100 kV from one or more points of connection”) was just filed with this Commission. 
Petition of the North American Electric Reliability Corporation for Approval of Revisions to the NERC 
Rules of Procedure Regarding Computational Load and Request for Expedited Action, N. Am. Elec. 
Reliability Corp., Docket No. RR27-1 (Oct. 21, 2026), eLibrary No. 20261021-5204.

- 5 - 
clarification is also consistent with the Commission’s Show Cause Order and MISO’s 
apparent intent not to reach distribution-connected loads with its proposed 
Interconnection Reliability Requirements. 
B. 
There remains uncertainty as to how Transmission Customers 
can rely on their agreements with Large Loads to effectuate 
compliance. 
MISO reiterates that “[t]he proposed Tariff expressly accommodates contractual 
arrangements between the Transmission Customer and the Large Load,”18 but its Answer 
fails to provide more details as to how those contractual arrangements will be 
accommodated in practice. Clarification of these implementation details are important to 
ensure that Transmission Customers are not unduly burdened by provisions intended to 
address reliability concerns caused by Large Loads. Midwest TDUs do not repeat all of 
clarification issues raised in our earlier Comments that should be addressed,19 but we 
highlight two specific shortcomings in MISO’s Answer.  
First, although MISO’s Answer acknowledges that “an Agreement assigning 
relevant performance and information duties to the Large Load may be part of a sufficient 
compliance showing,”20 it appears to reject the idea that agreements between a Large 
Load and the Transmission Customer can enable the Large Load to provide information 
directly to MISO. MISO states that it “must be able to obtain, through the Transmission 
Customer, all information and operational access necessary” and that agreements can 
“establish[] the Transmission Customer’s access to the information needed for 
 
18 MISO Answer at 28.  
19 Midwest TDUs Comments at 9-15.  
20 MISO Answer at 28 (emphasis added).

- 6 - 
compliance.”21 MISO does not explain why it could not accept relevant information 
directly from the Large Load where a Large Load-Transmission Customer agreement 
expressly assigns compliance responsibility to the Large Load.  
To the extent a Large Load enters into an agreement with the Transmission 
Customer to expressly take on identified responsibilities for complying with 
Interconnection Reliability Requirements, MISO should not encumber that compliance 
by insisting that the Transmission Customer act as a middleman. While MISO says it 
“will continue working with Transmission Customers and Large Loads through 
implementation to facilitate efficient compliance and provide education regarding the 
new requirements,”22 the Commission should not permit MISO’s apparent insistence that 
information be needlessly funneled through the Transmission Customer. Where a Large 
Load agrees to take on responsibility for compliance with an Interconnection Reliability 
Requirement, requiring the Transmission Customer to pass information from the Large 
Load to MISO serves as a barrier to implementing agreements that facilitate efficient and 
effective compliance.  
Second, MISO’s Answer stops short of confirming that the list of potential 
consequences in proposed section 37A is the exclusive list of consequences for 
noncompliance with the proposed Interconnection Reliability Requirements.23 And while 
MISO states that this list is “not an automatic penalty schedule,”24 MISO does not state 
 
21 MISO Answer at 29 (emphasis added).  
22 Id. 
23 Id.  
24 Id. (emphasis added)

- 7 - 
whether, and in what circumstances, it might seek to impose penalties under section 37A 
despite none being explicitly identified in that provision. Nor does it clarify (either in its 
Answer or with revised proposed Tariff language) the scope of the potentially broad 
catchall for “other remediation action(s)” in the provision of section 37A. As explained in 
Midwest TDUs’ Comments (at 13), it would be inappropriate to impose punitive 
consequences such as financial penalties on the Transmission Customer when an 
Interconnection Reliably Requirement is not met by the Large Load assigned compliance 
responsibility under an agreement. In these circumstances, the Tariff language in section 
37A should be clear that consequences of non-compliance should be tailored to address 
and prevent the reliability risks posed by Large Loads. 
Requiring additional clarity on these issues does not require MISO to establish 
direct relationships with all Large Loads, nor does it alter that the Transmission Customer 
is the entity taking Transmission Service of behalf of the Large Load. Rather, Midwest 
TDUs’ Comments raised narrow questions about how MISO will effectuate agreements 
between a Large Load and the Transmission Customer where the Large Load has agreed 
to take on responsibilities for compliance with one or more of the Interconnection 
Reliability Requirements. Given that the Large Loads are the source of the reliability 
concerns driving the need for the Interconnection Reliability Requirements, it is 
appropriate for MISO to engage with those Large Loads that enter into agreements with a 
Transmission Customer to take on responsibility for compliance with those 
Requirements. Doing so will result in more efficient and effective implementation of 
these important reliability requirements, without requiring a direct contractual

- 8 - 
relationship between MISO and the Large Load or relieving the Transmission Customer 
from its ultimate obligations under the MISO Tariff.  
CONCLUSION 
For the reasons discussed above, and in Midwest TDUs’ Comments, the 
Commission should 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 
October 28, 2026

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 28th day of October, 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