The 700-megawatt Trimount battery that Jupiter Power wants to build on a former Exxon Mobil oil-storage site in Everett, Massachusetts, would sit about four miles north of Boston. With 2.8 gigawatt-hours of stored energy, it would rank among the largest battery installations in the country and be by far the largest in New England. Construction is slated to begin in 2027.
Help yourself and the planet: The Cool Down makes it easy to help yourself while helping the planet, with smart, simple changes to save more and waste less in your everyday life.
We may earn a commission if you sign up.
The project arrives as Massachusetts leans harder on storage than nearly any other state. Canary Media reported on Oct. 26 that the commonwealth has already cleared its first 1-gigawatt target for 2025 and now counts more than 1.6 gigawatts of batteries, while officials talk about a ceiling of 10 gigawatts by 2035. Developers, regulators and neighbors are now arguing over how quickly that much equipment can be sited, connected to the grid and paid for.
Trimount in Everett and the Boston load pocket
According to Canary Media’s reporting on Trimount, the battery would tie into a major substation linking Boston to the wider New England grid, at a pinch point engineers call a load pocket. Jupiter Power, an Austin, Texas developer, is seeking approval from the Massachusetts Energy Facilities Siting Board and hopes to secure utility contracts later in 2026. If the schedule holds, ground is broken in 2027 and the plant operates by late 2028 or early 2029.
Hans Detweiler, a Jupiter Power development executive, told Canary Media that storage can save consumers money in several ways and that utilities will notice when a project of this size goes up. The open question, he said, is how regulators value it. Company-commissioned studies attach figures to the pitch: RLC Engineering estimated an avoided transmission cost of about $2.27 billion by sidestepping upgrades to high-voltage lines, including buried lines in dense urban areas, while Aurora Energy Research estimated roughly $1.6 billion in capacity-market savings over 20 years by deferring peaker plants. The developer paid for both analyses, which matters when weighing them.
Revenue is the awkward part. Under ISO New England’s storage-as-a-transmission-only-asset structure, approved by federal regulators in 2023, a battery used for transmission relief cannot also collect other income, and relief projects must be identified through multiyear regional planning. Trimount therefore expects to earn through the state’s Clean Peak Energy Standard and a utility contract rather than through payment for easing the Boston bottleneck.
Gigawatt targets: the 2030 law and the 2035 executive order
State law calls for 5,000 megawatts of operating storage by July 2030, according to ESS News coverage of the state’s first procurement. The Department of Energy Resources picked 1,268 megawatts across four projects on Dec. 23, 2025, from 13 bids: Trimount in Everett, Energizar in Somerset and Salt Cod in Chelsea from FlatIron Energy, and River Mill Storage in Tyngsborough from Rhynland Energy. Those developers now negotiate contracts with Eversource, National Grid and Unitil.
Gov. Maura Healey added a longer horizon on March 16, 2026, in Executive Order 654. It sets a goal of 5 gigawatts of storage online or under development by the end of 2035, listed apart from a 10-gigawatt overall target for new energy, and asks the Department of Energy Resources to keep evaluating the number. Canary Media reads the combined ambition as 10 gigawatts of batteries by 2035, the highest among the 13 states with battery procurement targets, against roughly 23 gigawatts already operating in California.
Elizabeth Mahony, commissioner of the Department of Energy Resources, framed the logic in operating terms: with storage on the system, the state can deploy it at different times to manage load. A second solicitation drew 35 bids, with selections expected in February. Siting rules effective July 1 let the Energy Facilities Siting Board approve storage projects of 100 megawatts or more, with decisions due within 15 months.
The policy scaffolding is older than the targets. Massachusetts launched its Energy Storage Initiative in 2015 under then-Gov. Charlie Baker, and the Clean Peak Standard, in effect since 2020 and described by Canary Media as a first in the country, pays renewable generators and storage owners to deliver power during peak demand. Aaron Lang, a partner at Foley Hoag, calls the state’s policy framework promising and says he is optimistic about clearing the remaining hurdles, while Detweiler says developers need stable rules across a permitting and procurement process that runs for years.
Grid-upgrade bills, local fights and fresh financing
Not every project survives the process. A 125-megawatt battery in Tewksbury was canceled in September after a $65 million grid-upgrade estimate, and Canary Media notes that many ISO New England estimates exceed $200 million. Erin Smith of the Environmental League of Massachusetts says the state is ahead of the pack on encouraging batteries but expects the cost of upgrades to be debated. Residents in Oakham are fighting a 180-megawatt proposal over fire and water-contamination worries, and a Westfield project was canceled last year for similar reasons.
Capital is still moving. Canary Media places a 250-megawatt battery in a town next to the Trimount site, and pv magazine USA reported in October that Flatiron Energy closed $850 million in financing for it. Todd Olinsky-Paul of the Clean Energy States Alliance argues that public fear of battery fires often stems from misinformation, a view set against the Moss Landing fire that Canary Media cites; newer systems use different technology and stronger safety protocols.
What remains unresolved is whether the Siting Board and a Massachusetts utility sign off on Trimount on the timeline Jupiter Power describes, and whether the value of relieving a Boston load pocket ever becomes payable income. Until those decisions land, the 700-megawatt figure is a plan, not a commitment.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
Help yourself and the planet: Get The Cool Down →
We may earn a commission if you sign up.
More from Morning Overview
- Hybrids have 15% fewer problems than gas cars, while EVs and plug-in hybrids have about 80% more, Consumer Reports finds
- Regulators cleared the first U.S. small modular reactor, 4 months early
- Lake Powell sank to a record 3,517 feet, nearing the level that stops Glen Canyon Dam’s turbines
- Seven of Earth’s nine planetary boundaries are breached, and all seven are worsening
