ER27-432-000 · 2026-11-06 · Southwest Power Pool, Inc.
SPP proposes conditional large-load service revenue credits for its western zones
Back to sections and commentaryPDF page 1
November 6, 2026
The Honorable Debbie-Anne A. Reese
Secretary
Federal Energy Regulatory Commission
888 First Street, N.E.
Washington, D.C. 20426
Re:
Southwest Power Pool, Inc., Docket No. ER27-____-000
Submission of Tariff Revisions to Revise Schedule 15 and Attachment
T for the SPP West Region
Dear Secretary Reese:
Pursuant to Section 205 of the Federal Power Act (“FPA”), 16 U.S.C. § 824d,
and Section 35.13 of the Federal Energy Regulatory Commission’s (“Commission”)
Regulations, 18 C.F.R. § 35.13, Southwest Power Pool, Inc. ("SPP") submits revisions
to Schedule 15 and Attachment T of its Open Access Transmission Tariff (“Tariff”)1
to add provisions for Conditional High Impact Large Load Service (“CHILLS”) for
pricing Zones in the SPP West Region, and to make other clarifying edits.
SPP respectfully requests that the Commission accept the proposed revisions,
find the revisions just and reasonable, and set an effective date of February 1, 2027.
I.
BACKGROUND
A.
SPP’s Regional Transmission Organization Expansion
On April 1, 2026, SPP expanded its Regional Transmission Organization
(“RTO”) into the Western Interconnection.2 Specifically, the following utilities now
1
Southwest Power Pool, Inc., Open Access Transmission Tariff, Sixth Revised
Volume No. 1. References in this filing to "Tariff" refer to the version of SPP’s
Tariff currently in effect. "Proposed Tariff" refers to a version reflecting the
revisions proposed in this filing. All capitalized terms not otherwise defined in
this filing shall have the definitions assigned by the Tariff.
2
The revisions to effectuate the expansion were filed in Docket Nos. ER24-2184
and ER24-2185. Southwest Power Pool, Inc., Submission of Revisions to
Tariff, Bylaws, and Membership Agreement to Expand the Regional
Transmission Organization into the Western Interconnection (Part 1 of 2),
Docket No. ER24-2184-000 and (Part 2 of 2), Docket No. ER24-2185-000
(June 4, 2024). All citations to the “SPP Expansion Filing” are to the Part 1
filing in Docket No. ER24-2184-000.The Commission accepted the revisions
to SPP’s governing documents in a series of orders. Sw. Power Pool, Inc., 190PDF page 2
The Honorable Debbie-Anne A. Reese
November 6, 2026
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include their transmission facilities in the Western Interconnection under SPP’s Tariff:
Basin Electric Power Cooperative (“Basin Electric”); Colorado Springs Utilities
(“CSU”); Deseret Generation and Transmission Cooperative; Platte River Power
Authority (“Platte River”); Tri-State Generation and Transmission Association, Inc.
(“Tri-State”); Western Area Power Administration – Colorado River Storage Project
Management Center (“WAPA-CRSP”); Western Area Power Administration – Rocky
Mountain Region (“WAPA-RMR”); and Western Area Power Administration – Upper
Great Plains Region (“WAPA-UGP”) (collectively, the “Expansion Members”). Basin
Electric, Tri-State, and WAPA-UGP were already Members of the SPP RTO and, with
the expansion of the SPP RTO, expanded their SPP RTO participation with the
inclusion of additional transmission facilities in the Western Interconnection.
SPP established five new transmission pricing Zones in Attachment H of the
Tariff in order to effectuate the integration of the new transmission facilities: 100, 101,
102, 103, and 104.3 SPP also added the “Incremental Market Efficiency Use”
provisions in the Tariff.4 In addition, SPP included a new Schedule 14 for the DC Tie
Access Charge.5
B.
Revisions to Add CHILLS
On February 10, 2026, SPP submitted revisions to the Tariff to add CHILLS to
allow High Impact Large Loads (“HILL”) to be served with non-firm conditional
transmission service.6 The Commission accepted the provisions in a series of orders.7
C.
Purpose of Filing
At the time of the CHILLS Filing, the new pricing Zones for the SPP West
Region had not yet been established in the Tariff. SPP submits this filing to include the
pricing Zones in Schedule 15 of the Tariff, and to also add CHILLS provisions to
FERC ¶ 61,169 (2025); Sw. Power Pool, Inc., Letter Order, Docket No. ER24-
2184-002 (July 11, 2025).
3
SPP Expansion Filing at 91.
4
SPP Expansion Filing at 52-53.
5
SPP Expansion Filing at 48.
6
Submission of Tariff Revisions to Add Conditional High Impact Large Load
Service of Southwest Power Pool, Inc., Docket No. ER26-1323-000 (Feb. 10,
2026) (“CHILLS Filing”).
7
Sw. Power Pool, Inc., 195 FERC ¶ 61,196 (2026); Sw. Power Pool, Inc., Letter
Order, Docket No. ER26-1323-002 (Oct. 26, 2026).
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The Honorable Debbie-Anne A. Reese
November 6, 2026
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certain Rate Sheets for Point-To-Point Transmission Service under Attachment T of
the Tariff. SPP also proposes other clarifying edits to Attachment T.
II.
DESCRIPTION OF AND JUSTIFICATION FOR PROPOSED TARIFF
REVISIONS
A.
Schedule 15
In the CHILLS Filing, SPP proposed a new Schedule 15, to establish charges
for CHILLS.8 SPP proposes to add pricing Zones 100, 101, 102, 103, and 104 under
Section 1 of Schedule 15:
Zone 100:
Colorado Springs Utilities
Zone 101:
Platte River Power Authority
Zone 102:
Tri-State G&T Association – West
Zone 103:
Colorado River Storage Project Zone
Zone 104:
Loveland Area Projects Zone
These revisions are just and reasonable because they effectuate the intent of the
CHILLS Filing already accepted by the Commission and will allow those entities in
the SPP West Region that take CHILLS to also pay for the use of the transmission
facilities located in those newly formed Zones in the SPP West Region.
B.
Attachment T
Attachment T includes the rate sheets for Point-To-Point Transmission Service
for all applicable Transmission Owners under the Tariff. SPP proposes to revise the
following rate sheets.
1.
Rate Sheets for CSU, Platte River, and WAPA-CRSP
SPP proposes the following revisions to the rate sheets for CSU, Platte River,
and WAPA-CRSP:
Point-To-Point Transmission Service and Conditional High Impact
Large Load Service Revenue Crediting for Point-To-Point Rates
Rates for Point-To-Point Transmission Service under this Attachment T
shall reflect any adjustments for Schedule 7 and 8 revenues, and
Schedule 15 revenues, and revenues distributed and allocated under
Attachment AU, implemented in accordance with Section 34.1(2) of
this Tariff. The rates, including any applicable adjustments for
Schedule 7 and 8 revenues, and Schedule 15 revenues, and revenues
8
CHILLS Filing at 29-30.
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The Honorable Debbie-Anne A. Reese
November 6, 2026
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distributed and allocated under Attachment AU, shall be set forth in the
RRR File.9
First, SPP adds a reference to Schedule 15 to appropriately adjust the Point-To-
Point Transmission Service Rates for any revenues received for Schedule 15 charges.
These proposed changes to add a reference to Schedule 15 revenues are just and
reasonable because they will appropriately adjust the Point-To-Point Transmission
Service Rates for any revenues received for Schedule 15 charges. The changes are
consistent with the revisions to other rate sheets accepted by the Commission in the
CHILLS Filing.
Second, SPP removes the references to Attachment AU revenues. Due to an
administrative error, SPP mistakenly included references to Attachment AU revenues
in the rate sheets for CSU and Platte River in the SPP West Region. As explained in
the SPP Expansion Filing, Attachment AU revenues are allocated only to Transmission
Owners in the SPP East Region.10
2.
Rate Sheets for Loveland Area Projects, SPP West Region
Average, and Tri-State G&T Association-West
SPP proposes the following revisions to the rate sheets for Loveland Area
Projects, SPP West Region Average, and Tri-State G&T Association-West:
Point-To-Point Transmission Service Revenue Crediting for Point-
To-Point Rates
Rates for Point-To-Point Transmission Service under this Attachment T
shall reflect any adjustments for Schedules 7, and 8, 14, and 15
revenues, and Incremental Market Efficiency Use revenues, and
revenues distributed and allocated under Attachment AU, implemented
in accordance with Section 34.1(2) of this Tariff. The rates, including
any applicable adjustments for Schedules 7, and 8, 14, and 15 revenues,
and Incremental Market Efficiency Use revenues, and revenues
distributed and allocated under Attachment AU, shall be set forth in the
RRR File.
9
SPP also includes a ministerial edit to the rate sheet for CSU to correctly reflect
CSU’s Addendum number under Attachment H of the Tariff.
10
SPP Expansion Filing at 56. See also Tariff, Attachment AU, Section I (“Such
revenues…shall be allocated to Transmission Owners in the SPP East Region
based on the estimated flow impacts resulting from energy transfers between
MISO north and south subregions, as described in this Attachment AU.”).
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November 6, 2026
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First, SPP adds a reference to Schedule 14 for the DC Tie Access Charge. The
DC Tie Access Charge is defined as “[a] charge on a transmission reservation utilizing
a West DC Tie that sinks outside of the Zone where the West DC Tie is located.”11 The
Transmission Customer is responsible for the DC Tie Access Charge determined in
Schedule 14 of the Tariff. SPP adds this reference to the rate sheets where the DC Tie
Access Charge is applicable.
Second, SPP adds a reference to Schedule 15 to appropriately adjust the Point-
To-Point Transmission Service Rates for any revenues received for Schedule 15
charges. The proposed changes to add a reference to Schedule 15 revenues are just and
reasonable because they will appropriately adjust the Point-To-Point Transmission
Service Rates for any revenues received for Schedule 15 charges. The changes are
consistent with the revisions to other rate sheets accepted by the Commission in the
CHILLS Filing.
Third, SPP adds a reference to Incremental Market Efficiency Use revenues.
The Incremental Market Efficiency Use Charge is “[a] market recovery mechanism to
compensate West DC Tie Transmission Owners for the expected loss of life of certain
West DC Tie facilities due to increased utilization of the West DC Ties by the
Integrated Marketplace.”12 SPP adds this reference to the rate sheets where Incremental
Market Efficiency Use revenues are applicable.
Fourth, SPP removes the reference to Attachment AU revenues. Due to an
administrative error, SPP mistakenly included references to Attachment AU revenues
rate sheets for Loveland Area Projects, SPP West Region Average, and Tri-State G&T
Association-West in the SPP West Region. As explained in the SPP Expansion Filing,
Attachment AU revenues are allocated only to Transmission Owners in the SPP East
Region.13
III.
EFFECTIVE DATE
For all the reasons discussed in this transmittal letter, SPP requests that the
Commission accept the proposed revisions to the Tariff to become effective February
11
Tariff, Part I, Section 1 – Definitions D.
12
Tariff, Part I, Section 1 – Definitions I.
13
SPP Expansion Filing at 56. See also Tariff, Attachment AE, Section I (“Such
revenues…shall be allocated to Transmission Owners in the SPP East Region
based on the estimated flow impacts resulting from energy transfers between
MISO north and south subregions, as described in this Attachment AU.”).
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1, 2027, which is not less than 60 days or more than 120 days prior to the submission
of this filing as required by the Commission.14
IV.
ADDITIONAL INFORMATION
A.
Documents submitted with this filing:
In addition to this Transmittal Letter, SPP provides with this filing Clean
and Redlined Tariff revisions under the Sixth Revised Volume No. 1.15
B.
Service:
SPP has electronically served a copy of this filing on all its Members,
Transmission Customers and Market Participants. A complete copy of
this filing will be posted on the SPP web site, www.spp.org, and is also
being served on all affected state commissions.
C.
Requisite agreements:
There are none.
D.
Communications
Correspondence and communications with respect to this filing should
be sent to, and SPP requests the Secretary to include on the official
service list, the following:
Justin A. Hinton
Senior Attorney
Southwest Power Pool, Inc.
201 Worthen Drive
Little Rock, AR 72223
Telephone: (501) 482-2468
jhinton@spp.org
Tessie Kentner
Director & Associate General Counsel
Southwest Power Pool, Inc.
201 Worthen Drive
Little Rock, AR 72223
Telephone: (501) 688-1782
tkentner@spp.org
14
18 C.F.R. § 35.3(a)(1).
15
Attachment T for the WAPA-CRSP Zone contains language in italics, which is
pending before the Commission in Docket No. ER26-1136. SPP requests that
the Commission accept the proposed revisions to this tariff sheet subject to the
outcome of hearing and settlement judge procedures in Docket No. ER26-1136.
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November 6, 2026
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V.
CONCLUSION
For the foregoing reasons discussed in this transmittal letter, SPP respectfully
requests that the Commission find the proposed revisions just and reasonable and not
unduly discriminatory or preferential, and issue an order accepting the Tariff revisions
with an effective date of February 1, 2027.
Respectfully submitted,
/s/ Justin A. Hinton
Justin A. Hinton
Southwest Power Pool, Inc.
201 Worthen Drive
Little Rock, AR 72223-4936
Attorney for
Southwest Power Pool, Inc.