FERC has approved ISO-NE’s proposal to replace its Forward Capacity Market with a prompt market, cutting the time between auctions and commitment periods from more than three years to about one month (ER26-925).
The new rules will take effect for the 2028/29 capacity commitment period (CCP), which begins June 1, 2028. ISO-NE held its last Forward Capacity Auction, FCA 18, in February 2024 for the 2027/28 CCP.
FERC’s March 30 approval marks the end of the first phase of ISO-NE’s Capacity Market Reforms (CAR) project. The RTO is amid stakeholder discussions on the second phase of the project, which centers around capacity accreditation changes and the division of annual CCPs into winter and summer seasons.
Under the new design, only resources that have achieved commercial operations will be allowed to participate in the Annual Capacity Auctions. A key motivation driving the prompt market proposal was ISO-NE’s desire to eliminate “phantom entry,” which occurred in the FCM when non-commercial resources obtained capacity supply obligations (CSOs) but failed to come online in time for the commitment period.
ISO-NE has also argued that the new auction format will help protect the region against increasing uncertainty in load forecasts. While New England states have set ambitious electrification goals, the RTO has scaled back its electrification forecasts in recent years because of slower-than-expected electrification adoption. And while the data center boom has yet to hit New England, the potential for new large loads adds additional uncertainty to the forecasts.
“The combination of forecasted demand growth into the next decade, and the uncertainty over the extent of such growth, underscores the value in transitioning from the three-year forward market construct to the proposed prompt market construct,” ISO-NE wrote in its filing.
Accurate demand forecasting “will be especially important when accounting for data centers and other large load proposals, which are often highly uncertain in terms of proposal attrition rates, relative construction time and electric demand characteristics,” it added.
The approved changes also include provisions affecting resource deactivations, resource qualification and the auction clearing mechanism, and will eliminate the need for annual capacity reconfiguration auctions.
In the prompt market, the resource retirement process will be decoupled from the auction qualification process. Retiring resources must submit deactivation notices a year prior to the applicable commitment period. In the forward market, ISO-NE processed retirements about four years prior to each CCP.
The RTO has said the reduced notification period will enable resources to make retirement decisions with more up-to-date market information, while still giving the region some time to respond to deactivations. In the NEPOOL discussions of the changes, some stakeholders expressed concern that reducing the notification timeline will increase the likelihood and duration of reliability-must-run agreements.
All commercially available capacity resources that do not deactivate will be required to participate in the auction.
The new qualification process includes a February deadline for data submission and an April deadline for new resources to demonstrate they have achieved commercial operations. Each auction will be held in early May prior to the June 1 start of each CCP.
The move to a prompt auction will affect which costs that participants are allowed to incorporate into capacity offers. Bids are supposed to reflect the incremental cost of assuming a CSO, and costs associated with investments made in resources prior to the auction cannot be included in bids.
But ISO-NE argued that this will “not necessarily lower capacity offer prices,” as it impacts just one factor affecting offer prices in the auction. The RTO told FERC that the transition to a prompt market will allow for more efficient market outcomes but will not systematically influence the trajectory of clearing prices.
“The change in the timing of the capacity auction does not change the fundamental pricing dynamics within the capacity market,” Chris Geissler, director of economic analysis at ISO-NE, wrote in testimony supporting the RTO’s proposal.
The prompt market proposal received near-universal support from the NEPOOL Participants Committee, and a range of commenters expressed general support for the RTO’s filing with FERC. (See NEPOOL Supports First Phase of ISO-NE Capacity Market Reform.)
The New England Power Generators Association (NEPGA) expressed concern about how the RTO would calculate the competitive price offer threshold, which determines whether an offer will be subject to review by the ISO-NE Internal Market Monitor. While NEPGA has argued that ISO-NE’s proposal to maintain its existing methodology would make it reliant on stale data, ISO-NE has committed to evaluating potential issues prior to the 2028/29 CCP.
FERC said the new design will reduce both supply and demand uncertainty. It agreed the retirement changes “will allow market participants to make their retirement decisions based on better information about market conditions, revenues, costs and the remaining economic life of the resource.”
“We’re pleased to receive the commission’s approval on the first phase of capacity market reforms, which enjoyed broad support from stakeholders and the New England states,” ISO-NE said in a statement. “We look forward to this collaboration continuing as we develop the second phase of reforms ahead of a filing with the commission later this year.”
While the prompt market changes are intended to be able to stand on their own, ISO-NE hopes to implement both phases of the CAR project for the 2028/29 CCP. But the second phase is widely considered to be the more controversial component, and there is no guarantee ISO-NE will obtain approval of these additional changes in time for the commitment period.
