Massachusetts has advanced its clean energy goals with the filing of a draft Request for Proposals (RFP) aimed at securing 1,500 megawatts of mid-duration energy storage capacity. Filed jointly by the Department of Energy Resources (DOER) and the state’s electric distribution companies (EDCs) on May 5, the draft was submitted to the Department of Public Utilities (DPU), which is now accepting public comments through May 30, with reply comments due by June 6.
This is the first of at least four solicitations designed to meet the mandate of 5,000 MW of energy storage by July 31, 2030, as outlined in the 2024 Act Promoting a Clean Energy Grid, Advancing Equity, and Protecting Ratepayers. The target systems are mid-duration, defined as capable of continuous energy discharge for four to ten hours.
Under the draft RFP, eligible projects must be transmission-connected and range in size from 40 MW to 1,000 MW. All projects must begin commercial operations by January 1, 2030. Bidders may propose contracts lasting up to 30 years, though those involving Clean Peak Energy Certificates (CPECs) are advised to cap terms at 20 years, given the program’s scheduled conclusion in 2050. A non-refundable bid fee of $500 per MW of proposed capacity is required.
The evaluation process is structured in three stages. Stage one screens projects for eligibility, viability, and readiness. Stage two scores proposals on a 100-point scale, with 80 points focused on cost and environmental benefits, and 20 points evaluating qualitative factors such as community benefits, safety, and economic development. Stage three involves a holistic portfolio review by an evaluation team including DOER, the EDCs, the Executive Office of Economic Development, and an Independent Evaluator.
An Independent Evaluator is tasked with ensuring a fair and transparent selection process. All non-confidential bid materials will be made public, and a bidders’ conference will be held to promote broad participation. Selected bidders must negotiate long-term contracts with the EDCs, provide financial security, and enter into a memorandum of understanding with DOER to formalize commitments to environmental justice and low-income ratepayers. Contracts will require approval by the DPU, and potentially the Federal Energy Regulatory Commission (FERC) for federally regulated rates.
The proposed timeline begins with the issuance of the RFP on July 31, 2025, followed by a bidders’ conference on August 14 and a proposal deadline of September 10. Project selection is expected by December 9, with contracts finalized by March 27, 2026, and submitted for DPU approval by April 24, 2026.
This draft RFP represents a major milestone in Massachusetts’ efforts to modernize its electric grid while promoting equity and environmental stewardship.
