Mass. utilities ink 4.5 GWh energy storage deals
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- Eversource Energy, National Grid and Unitil filed long-term contracts with developers of three utility-scale storage projects totaling 1,068 MW / 4,472 MWh of capacity targeted for operation by 2030, with Eversource also piloting localized virtual power plants in the same Greater Boston and southeastern Massachusetts zones.
- Jupiter Power's 700 MW / 2,800 MWh Trimount project — to rise on 20 acres at a former oil terminal in Everett, just north of Boston, and connect at the nearby Mystic substation — will be New England's biggest battery installation when it fires up; its capacity splits 200 MW for Unitil's Fitchburg Gas & Electric Light subsidiary and 500 MW for National Grid's Massachusetts subsidiaries.
- Flatiron Energy is developing two projects: the 250 MW / 1,000 MWh Energizar at a former industrial site in Chelsea (operations targeted for Q2 2027) and the 168 MW / 672 MWh Salt Cod on an 11-acre section of the shuttered Montaup Power Plant waterfront in Somerset, MA (operations targeted for late 2028).
- The contracts advance Massachusetts's 5 GW storage-by-2030 goal, and follow Democratic Gov. Maura Healey's earlier announcement of plans to procure an additional 5 GW by 2035 as part of a broader 15 GW non-emitting capacity push.
- Financial analyses filed with the Massachusetts Department of Public Utilities project the three facilities will modestly reduce most customers' monthly bills over the next 5 to 15 years, while providing clean peaking capacity and easing transmission congestion.
- A fourth project, Rhynland Energy's 200 MW River Mill Storage, came out of the same initial solicitation but has not yet signed a long-term contract; a second solicitation is now seeking 250-300 MW of distribution-connected storage, with further RFPs targeting 3,500 MW more by July 2030.
Why it matters: Most Massachusetts ratepayers should see modest monthly bill reductions over the next 5 to 15 years, per filings with the state Department of Public Utilities — a concrete customer benefit tied directly to three new grid-scale batteries. Trimount alone will set a regional battery-size record while reusing a former oil terminal, signaling how brownfield-to-battery redevelopment is becoming the state's template for both grid reliability and cost control.
