DOER Selects 1.3 GW of Energy Storage in First Section 83E Procurement

On December 19, 2025, the electric distribution companies announced that the Massachusetts Department of Energy Resources (DOER) had selected 1,268 MW of energy storage projects through the first Section 83E solicitation (83E Round 1). The bid evaluation process included monitoring and assistance by an Independent Evaluator, consistent with the requirements of the Request for Proposals (RFP).

DOER selected four projects, together totaling 1,268 MW of energy storage capacity, as part of the Round 1 procurement, all 4 hour duration:

• Energizar, a storage project under development by FlatIron Energy in Chelsea, Massachusetts, reported at approximately 250 MW
• River Mill Storage, a storage project under development by Rhynland Energy in Tyngsborough, Massachusetts, with publicly reported capacity varying across disclosures
• Trimount ESS, a large-scale storage project under development by Jupiter Power in Everett, Massachusetts, reported at up to 700 MW
• Salt Cod, a storage project under development by FlatIron Energy in Somerset, Massachusetts, reported at approximately 168 MW

Under the Round 1 RFP, bidders were permitted to offer less than a project’s full nameplate capacity, and DOER retained discretion to select partial quantities from individual bids. Unfortunately for market participants and market analysts alike, however, DOER did not disclose the specific quantities selected from each project. As a result, it is important to note that publicly reported project sizes should not be interpreted as the awarded capacity for each project.

While the solicitation authorized procurement of up to 1,500 MW of mid-duration energy storage (defined as storage for 4-10 hours), DOER selected a smaller total quantity. We anticipate this reflects a deliberate decision to avoid accepting higher-priced bids or projects with later commercial operation dates, rather than a lack of sufficient interest or eligible supply.

DOER emphasized, as in other procurements in which it has been involved, that selection does not constitute final contract approval. As the agency noted, “the final acceptance of the bids and the award of contracts is conditional upon successful negotiation of mutually acceptable long-term contracts between the bidders and each of the Massachusetts Distribution Companies, as well as required regulatory approvals of such contracts, as provided by the RFP.”

The selected projects will now proceed to contract negotiations with the electric distribution companies, followed by review by the Massachusetts Department of Public Utilities. As with prior Section 83 procurements, the pace and outcome of this phase will be closely watched, particularly given the fixed-price, pay-as-bid structure of the solicitation and ongoing uncertainty related to interconnection costs, equipment pricing, and construction timelines.

The Round 1 outcome sets an important reference point for future Section 83E procurements. Subsequent solicitations are expected to expand eligibility to include distribution-connected resources, and may introduce alternative contract structures that bundle environmental attributes with energy, ancillary services or capacity services.

As the 83E solicitations progress, we will monitor them closely and include them in our modeling for our Clean Peak Market Outlook. As a reminder, your CPMO subscription allows you to schedule a 1 hour post briefing time with the CPMO team to discuss CPS matters.