83E Procurement Advances: Round 1 Clarifications and Round 2 Stakeholder Feedback
As previously discussed in our blog series, on July 31, 2025, the Massachusetts Department of Public Utilities (DPU) issued the final version of the 83E Request for Proposals (RFP) requiring Electric Distribution Companies (EDCs) to work with the Massachusetts Department of Energy Resources (DOER) to procure 1,500 MW of mid-duration (4-10 hours) energy storage. While stakeholders had pressed for broader modifications to the Draft RFP, the DPU adopted only a few targeted clarifications. In this blog post we present a summary of the bids submitted by developers.
Round 1 Bids Summary
| Project Name | Owner | Town/City | Size (MW) | Duration (h) | Expected COD |
| Agawam Energy Center | Longroad Energy | Agawam | 250 | 4 | N/A |
| Bear Swamp Pumped Hydro | Brookfield Asset Management | Florida | 88 | 4.5 | Operating |
| Brough Energy Storage | CleanCapital | Cheshire | N/A | N/A | 5/2029 |
| Energizar | FlatIron Energy | Chelsea | 250* | 4 | 9/1/2027 |
| Hammersmith | FlatIron Energy | N/A | 225 | 4 | 12/31/2029 |
| Hecate Energy Ward Hill Energy Center | Hecate Energy & CME | Haverhill | 310 | 4 | 1/1/2029 |
| Hillman Energy Center | East Point Energy | Tewksbury | 125 | 4 | Q4 2029 |
| Merlin Storage | CleanCapital | N/A | N/A | N/A | 5/2029 |
| Partridge Storage | CleanCapital | Pittsfield | N/A | N/A | 5/2029 |
| Revolution | FlatIron Energy | N/A | N/A | 4 | N/A |
| River Mill Storage | Rhynland Energy | Tyngsborough | 500 | 4 | 2028 |
| Salt Cod | FlatIron Energy | Somerset | N/A | 4 | 12/31/2028 |
| Trimount ESS | Jupiter Power | Everett | 700 | 4 | 6/1/2029 |
On September 10, 2025, DOER and the EDCs published redacted summaries of all Round 1 bids. Thirteen projects, totaling approximately 1,500 MW, were submitted, all of which are transmission-connected. Only Bear Swamp is a non-battery resource.
Round 2 Updates
DOER confirmed that subsequent solicitations will include distribution-connected resources. On July 31, DOER, the EDCs, and the Attorney General’s Office (RFP Drafting Parties) released a Request for Public Comment (RPC) on the Round 2 (83E II) solicitation, aiming to procure roughly 1 GW of additional mid-duration energy storage.
The Clean Peak Market Outlook (CPMO) team continues to monitor every stage of Massachusetts’ evolving Section 83E mid-duration storage procurements from DPU orders to DOER Q&A clarifications and stakeholder responses. Our subscriber-only analysis provides detailed tracking of bids, project eligibility, and insights valuable to contracting strategies.
An extended version of this blog post covering detailed stakeholder comments on Round 2, including eligibility, valuation, financing, aggregation, and contract structure, is available exclusively to Clean Peak Market Outlook (CPMO) subscribers.
To access the full version and receive ongoing coverage of Massachusetts’ mid-duration storage procurements, contact Bob Grace, Jim Kennerly or Madeline Frierson to learn more about CPMO subscription options.


