FERC recently issued two orders approving stipulation and consent agreements between the Office of Enforcement and Regulatory Accounting (“Enforcement”) and two jurisdictional utilities related to outages and derates (partial outages) that merit the attention of all regional transmission organization (“RTO”) Market Participants looking to avoid potentially expensive investigations and enforcement actions.
Green Mountain Power Corp. Settlement
On January 6, 2026, FERC issued an order (194 FERC ¶ 61,014) approving a settlement between Enforcement and Green Mountain Power Corp. (“Green Mountain”) to resolve Green Mountain’s alleged violation of the ISO New England Inc. (“ISO-NE”) Transmission, Markets, and Services Tariff (“ISO-NE Tariff”) and FERC’s Market Behavior Rules, 18 C.F.R. § 35.41 (2025). Green Mountain operates a run-of-the-river resource in Vermont (the “Resource”), which was reported as unavailable in the Generating Availability Data System (“GADS”) for 823 days from September 27, 2022, through December 27, 2024 (“the Relevant Timeframe”). However, Green Mountain only submitted outages for the Resource in ISO-NE’s Control Room Operations Window system (“CROW”) for 111 of those days, meaning Green Mountain failed to report an outage for 86.52% of the time that the Resource was unavailable during the Relevant Timeframe. The Resource had a Capacity Supply Obligation during the entire Relevant Timeframe.
Green Mountain admitted that it violated ISO-NE Tariff Sections III.1.7.20(f), which requires Market Participants to report their anticipated availability, and III.13.6.1.3.3(c), which requires Market Participants to report outages as detailed in the ISO-NE Business Practice Manuals. Green Mountain also admitted to violating FERC’s Market Behavior Rules by failing to properly report its outages and 18 C.F.R. § 35.41(b) by providing false or misleading information to ISO-NE regarding the outages. Green Mountain agreed to pay a civil penalty of $32,500 and disgorge unjust profits of $94,833.26 plus interest to ISO-NE, in addition to two years of compliance monitoring plus a potential third year at Enforcement’s discretion. The disgorgement was derived from the net capacity payments and net reconfiguration auction payments Green Mountain received for the Resource in the Relevant Timeframe.
Tenaska Power Services Co. Settlement
In addition, on January 12, 2026, FERC issued an order (194 FERC ¶ 61,029) approving a settlement between Enforcement and Tenaska Power Services Co. (“TPS”) as the Lead Market Participant for the natural gas-fired Berkshire Generator to resolve TPS’s alleged violations of the ISO-NE Tariff and FERC’s Market Behavior Rules. Berkshire Power owns the Berkshire Generator, an ISO-NE capacity resource, and compensates its affiliate TPS to be the Lead Market Participant for the resource. On the relevant dates, the Berkshire Generator had a Capacity Supply Obligation of 229 MW and an Economic Maximum (“EcoMax”) of 251 MW. For market days January 11-12, 2021, the Berkshire Generator received a day-ahead award for every hour at its EcoMax. On January 11, shortly after 10:00 am, the natural gas pipeline serving the Berkshire Generator issued an Operational Flow Order (“OFO”), effectively curtailing the amount of gas that the Berkshire Generator could expect. TPS was able to locate available replacement gas for Berkshire Generator at an elevated price, but Berkshire Power did not authorize TPS to purchase additional fuel. Instead, Berkshire Power requested that ISO-NE derate the Berkshire Generator from 251 MW to 150 MW, an amount below both its award and Capacity Supply Obligation. Berkshire Power did not inform ISO-NE that there was available, though more expensive, fuel. ISO-NE put the Berkshire Generator in limited-energy generator status, which is a status for generators that, due to physical design considerations or environmental restrictions, are unable to operate continuously at full output on a daily basis. The Berkshire Generator produced energy at the lower 150 MW level until the OFO condition was lifted on January 12 and then resumed producing at its EcoMax.
Enforcement determined that TPS violated the ISO-NE tariff and FERC’s Market Behavior Rules, when its affiliate, Berkshire Power, avoided additional, more expensive fuel purchases that would have enabled the Berkshire Generator to run at its EcoMax consistent with its day-ahead awards during the OFO condition. Specifically, Enforcement found violations of ISO-NE Tariff Section III.13.6.1.1.1, requiring generators with Capacity Supply Obligations to offer at or above their obligations whenever the resource is physically available, and ISO-NE Tariff Section III.13.6.1.1.2, requiring offers to reflect the known operating characteristics of the resource, by modifying the real-time offers of the Berkshire Generator based on economic factors and not physical availability. Enforcement also found that TPS had violated 18 C.F.R. § 35.41(a) by failing to offer the Berkshire Generator consistent with the ISO-NE Tariff and 18 C.F.R. § 35.41(b) due to misrepresentations and omissions made to ISO-NE about the resource’s ability to operate at its Capacity Supply Obligation. TPS agreed to disgorgement of $78,354, plus interest, and a $51,000 penalty. TPS also agreed to one year of compliance reporting, with a second year at Enforcement’s discretion.
Discussion and Other Recent Settlements
Outage and derate issues can impact any resource type, and FERC’s Green Mountain and TPS settlements are reflective of FERC Enforcement’s ongoing interest in outage and derate reporting issues across varied generator types. In a 2024 settlement (192 FERC ¶ 61,205), Cordorva Energy admitted to inadvertently submitting inaccurate derates for their unit, another gas power plant, for approximately 3 months, resulting in $1,964,436 in capacity market overpayments, which were disgorged. Cordova Energy also agreed to a civil penalty of $370,000. In a 2025 settlement with Sonoran Entities (189 FERC ¶ 61,174), Enforcement found that the Sonoran Entities, among other issues, submitted outage cards to CAISO that would have indicated that their battery resource needed to be fully discharged in advance of the outage, which resulted in uneconomic Day-Ahead market awards and lead to improper uplift payments. The Sonoran Entities disgorged $2,473,265 and paid a civil penalty of $1,000,000.
Outage and derate issues can become of particular interest to Enforcement (and Market Monitors) during periods where the energy grid is stressed. In their 2024 settlement with Enforcement (189 FERC ¶ 61,185), Montpelier Generating Station, LLC and Rockland Capital, LP (collectively the “Montpelier Entities”) were found to have improperly entered a Maintenance Outage/Derate ticket in PJM’s systems during Winter Storm Elliott, rather than the correct Unplanned Outage/Derate, a forced outage. The Montpelier Entities used a separate, independent energy market scheduler. This difference in outage type allowed the Montpelier Entities to avoid Performance Assessment Interval penalties related to the winter storm. The avoided penalties, totaling $674,064, were disgorged plus interest and a civil penalty of $105,000 was assessed.
These recent Enforcement settlements suggest that outage and derate reporting is a readily potential source of a Market Monitor or Enforcement investigation for any Market Participant. In order to avoid the time, cost, penalties, and disgorgement potentially related to an Enforcement investigation, Market Participants should consider doing the following:
- Ensure that your policies and procedures are up-to-date and reflect guidance regarding outages and derates as detailed in the applicable Tariff and relevant Manuals;
- Review your policies and procedures with entities responsible for entering in outages on your behalf, including independent energy market schedulers;
- Review recent outages or derates, particularly during grid stress events, to ensure that your outage types, if any, are correct; and
- Evaluate whether a self-report to Enforcement and corrective action is appropriate if you identify an issue.
Please feel free to reach out to Nick Barber (nbarber@thompsoncoburn.com) or the Thompson Coburn Energy Group if you have any questions related to outage reporting or other potential energy issues.
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