FERC has rejected Tri-State Generation and Transmission’s proposed tariff designed to manage the projected massive growth in data center load confronting its Mountain West member utilities over the next decade (ER25-3316).
The commission’s Oct. 27 decision could call into question a growing push among utilities to develop such rulesets to insulate ratepayers from the financial and reliability risks stemming from the heavy energy demands of new data centers. (See Large-load Tariffs Touted as Alternative to ‘Side Deals’.)
Modeled on similar tariffs filed by other U.S. utilities, Tri-State’s High Impact Load Tariff would have established a biennial planning cycle for customer loads rated at 45 MW or higher, with the aim of weeding out speculative projects.
In its filing, the Colorado-based cooperative wrote that a “separate HIL planning cycle process is necessary because HILs are of a size that require significant generation capacity additions or procurement of long-term [power purchase agreements], which necessitates proper planning” to prevent ratepayers from bearing the financial burden of grid projects being completed “only for a HIL to not materialize.”
The proposed rules would have required Tri-State members and developers of HIL projects to undergo an evaluation process that included providing evidence that a developer had 90% site control of its project location and submitting an executed member-customer high-impact load (MCHIL) agreement and high-impact load agreement (HILA) to be executed between the utility member and Tri-State.
Developers of projects under 80 MW would also have been required to pay an evaluation fee starting at $35,000 plus $1,000/MW, with the fee increasing to $150,000 for projects between 80 and 200 MW and $250,000 for projects above 200 MW — levels Tri-Sate said were consistent with deposit thresholds under its large generator interconnection process.
The HILA also would have required a HIL customer to provide a minimum security deposit of $2.7 million/MW to offset the risk that the customer “begins commercial operations late [or] ceases operations before the expiration of the HILA term or the HIL does not operate at the expected level (or at all).”
‘A Job for the States Alone’
In rejecting the proposed rules, the commission largely agreed with protests by Data Center Coalition and infrastructure developer Eolian Energy, finding that “certain aspects” of Tri-State’s proposed tariff “appear to present an impermissible intrusion on retail rate regulation,” which falls under the purview of states and is not subject to FERC’s jurisdictional authority under the Federal Power Act.
“We find that several provisions of the HIL Tariff require specific terms and conditions of service by a utility member to an end-use HIL customer (i.e., a retail service) and make the MCHIL a condition of Tri-State’s agreement to provide wholesale service to its utility members to facilitate their retail service of large loads,” the commission wrote.
The commission noted the protesters’ argument that Tri-State was proposing to use a FERC-jurisdictional tariff to set the terms of retail sales by “dictating” the minimum amount of energy a large load customer must purchase at retail.
“For example, Data Center Coalition argues that mandating HIL customers enter into contracts with utility members that contain minimum monthly demand and energy requirements are terms of retail service that are beyond the commission’s authority to regulate. Eolian argues that the MCHIL is a retail agreement, and Tri-State’s failure to explain how the commission can approve a tariff provision that dictates the terms of retail service is a deficiency in Tri-State’s filing,” the commission wrote.
Tri-State did not provide “a sufficient basis” for FERC finding the proposal did not regulate the terms and conditions of a HIL customer’s retail service “in ways that are beyond the commission’s authority,” it said, pointing specifically to the HILA provision that requires a Tri-State utility member to enter into an MCHIL that sets the terms for energy sales from the member to its retail customer.
The commission also disagreed with Tri-State’s contention that FERC has authority to assert jurisdiction over the proposed HILT and HILA, “which condition Tri-State’s service to its utility members on those utility members’ HIL customers complying with certain terms and conditions of retail service.”
“We note that the plain language of the FPA bars the commission from regulating retail sales, and the Supreme Court has been clear: Specification of terms of sale at retail ‘is a job for the states alone.’”
The commission also rejected Tri-State’s argument that it should accept the HIL program because it is similar to the co-op’s FERC-approved demand response program in laying out key terms for utility member participation.
“We disagree because Tri-State’s demand response program does not place the terms and conditions on the retail sale of electricity; instead, it sets forth the technical requirements that a utility member’s demand response resources must meet in order for the utility member to qualify for incentive payments from Tri-State’s demand response programs,” the commission wrote.
Guidance for 2nd Attempt
But the commission left open the door for Tri-State to file a modified version of the HILT that does not infringe on retail rate regulation, outlining a handful of “concerns” about the tariff the co-op should address, including:
-
- insufficient evidence that the proposed security deposits are “appropriately sized to mitigate the risks Tri-State identifies”;
- insufficient explanation justifying why Tri-State should be able to terminate a utility member’s HILA for reasons beyond the member’s control, potentially after the member has already incurred construction costs to help serve the new load; and
- lack of justification for the “degree of discretion” Tri-State proposed to give itself in implementing various parts of the HILT, such as the evaluation criteria.
The commission also found that the tariff did not provide sufficient detail about the “interactions” between the proposed reliability and transmission criteria in the evaluation.
“We also note that Tri-State’s metrics for assessing the reliability criteria lack the necessary details for the commission to evaluate their effectiveness and whether they ensure not unduly discriminatory treatment across projects,” it wrote.
Reached for comment, a Tri-State spokesperson told RTO Insider: “While this is a disappointing result, FERC provided guidance to Tri-State that we can use to move forward toward our goal of creating a repeatable and fair process to bring high-impact loads to Tri-State and our members, while providing data centers and other large loads a transparent and fair process.
“We still are reviewing the order and determining our next steps, but there may be an opportunity to modify the tariff to address FERC’s comments and deliver the consistency our members seek, in responding to requests for service from heavy energy-users.”




