EL25-015

The docket concerns Otter Tail Power Company's petition for approval of an electric service agreement with Big Stone South Energy Storage Project, LLC (BSSEP), including associated tariff revisions. The filing adds a new electric service agreement with deviations to Otter Tail's summary of contracts with deviations. BSSEP is the only customer affected by this filing. The new agreement is set to be effective August 1, 2025, but no specific present or proposed rates are disclosed in the public documents. The petition also requests confidential treatment for certain proprietary and sensitive business information, including pricing and components of the rate formula, as trade secrets under South Dakota law 1, 2.

Key events and submissions in the proceeding regarding Otter Tail Power Company’s electric service agreement for Big Stone South Energy Storage Project, LLC and associated tariff revisions include:

- April 21, 2025: Otter Tail Power Company filed with the South Dakota Public Utilities Commission (SD PUC) for approval of a new electric service agreement with deviations, seeking confidential treatment for certain proprietary and sensitive information in the submission 1, 1.
- April 22, 2025: The SD PUC published notices and documentation reflecting the filing, including updates to the electric rate schedule (Section 16.00, summary of contracts with deviations) to add the new agreement. The effective date for the rate associated with this agreement is scheduled for August 1, 2025 2, 2, 2, 2, 2.
- May 14, 2025: The SD PUC staff sent the first set of data requests to Otter Tail Power Company and representatives for Big Stone South Energy Storage Project, LLC 3, 3, 3.
- May 28, 2025: Otter Tail Power Company responded to data requests from the SD PUC staff 4.
- August 1, 2025: The effective date for the new electric service agreement and the associated tariff schedule changes in South Dakota 5, 6, 2, 2, 5, 5, 6.

The only customer affected by this filing is Big Stone South Energy Storage Project, LLC (BSSEP) 2, 2, 2, 2.

The provided excerpts do not specifically identify explicit "areas of growth" in the context of this docket. However, based on the content, the docket primarily addresses the following key area of growth:

Execution of a new electric service agreement (ESA) with deviations for the Big Stone South Energy Storage Project, LLC (BSSEP):

Key considerations related to this area include:
- The agreement represents the addition of a new electric service contract with deviations from standard rate schedules, reflecting project-specific terms for BSSEP.
- This new agreement is effective August 1, 2025, and BSSEP is the only customer affected by this filing, indicating targeted growth in energy storage and possibly large customer services.
- No change in present or proposed rates is directly disclosed in the public filings, and the revenue impact is marked as "not applicable."
- Portions of the petition, including proprietary business information, pricing information, and customer-specific data, are considered trade secrets and have been filed under confidential treatment to protect sensitive details 1, 2.
- The filings note the need for commission approval of the new ESA and updates to the schedule reflecting the agreement with deviations, ensuring regulatory compliance and transparency in service changes 1, 1.

No other distinct areas of growth are detailed in the excerpts beyond the implementation of the new service agreement for BSSEP.

The docket contains minimal detail on specific financial and timeline risks or concerns. The filings and supporting documents primarily address the execution of a new electric service agreement with deviations for the Big Stone South Energy Storage Project, LLC, noting:

- The effective date of the new agreement is August 1, 2025.
- Present rates, proposed rates, and approximation of annual revenue impacts are all listed as "not applicable."
- Only Big Stone South Energy Storage Project, LLC is affected by this filing.
- The company seeks approval to update the schedule to reflect the new agreement with deviations.
- No explicit discussion of risks is included in the non-confidential record 1, 1.

Additionally, significant information related to financials, pricing, and proprietary details is marked as confidential and withheld from public disclosure, as it is considered trade secret data. This includes sensitive customer information, pricing information, and components of a formula to derive a fixed rate component. These confidential materials may contain more detail on financial and timeline risks, but are not available in the public excerpts 2, 2.

Therefore, based on the available public excerpts, no specific financial or timeline risks or concerns are discussed.

The primary stakeholders in this docket (Otter Tail Power Company's petition for approval of an electric service agreement for Big Stone South Energy Storage Project, LLC and associated tariff revisions) are:

- Otter Tail Power Company (the petitioner)
- Big Stone South Energy Storage Project, LLC (the customer and counterparty in the electric service agreement)
- South Dakota Public Utilities Commission (the regulatory body reviewing and approving the proposal)
- Valley Queen Cheese Factory, Inc. (another listed customer, but not directly involved in this specific agreement)
- Commission staff, including legal and regulatory analysts
- Counsel involved in the proceeding (e.g., Lauren D. Donofrio for Otter Tail, Lisa M. Agrimonti for Big Stone South Energy Storage Project, LLC) 1, 1

The available excerpts do not provide explicit information on which stakeholders are for or against specific proposals. However, Otter Tail Power Company and Big Stone South Energy Storage Project, LLC are parties to the proposed agreement and are presumed to be in favor of its approval. No opposition from other stakeholders is documented in the provided information.