For decades, ExxonMobil used a swath of industrial land near the Mystic River in Everett to store petroleum. Now, another Texas-based company wants to store a different sort of fuel there: lithium-ion battery power.

Jupiter Power this week announced plans to build a $500 million-plus battery energy storage system on a 20-acre portion of the former Exxon tank farm. With up to 700 megawatts of capacity, enough to provide backup power for around 500,000 homes for a few hours, the Jupiter project would be among the largest such projects in New England.

The unveiling of the “Trimount Energy Storage Facility” comes roughly one week before the nearby Mystic natural gas-fired power plant shuts down for good, with its remaining two units going into retirement. These battery-storage projects, relatively new here now, could become crucial as the New England grid grows increasingly reliant on solar and wind power. The batteries can provide juice when the sun isn’t shining and the wind isn’t blowing, as well as backup power for when demand peaks during cold snaps or particularly hot summer days.

“Battery storage is going to be quite important for New England to reach the clean energy goals that policy makers have,” Jupiter chief executive Andy Bowman said.

For Jupiter, which is owned by investment giant BlackRock, the plan is to start state and local permitting reviews later this year, although it has already begun preliminary talks with Everett Mayor Carlo DeMaria’s administration. An investment of this size would bring millions in new property-related tax revenue to the city, along with hundreds of construction jobs, though once it’s built, it would only need five to 10 full-time employees. The project would connect into the region’s grid through an Eversource substation next to the discontinued Mystic plant, on the city of Boston’s doorstep.

“It’s a great location,” said Bowman, who hopes to have the project running in 2027. “There’s the ability to deliver a lot of power there from the power plant that used to be there. We can interconnect efficiently [to the grid], without a lot of costs to ratepayers.”

Jupiter’s proposal would be just one component of a massive, mixed-use redevelopment for the roughly 100-acre former tank farm that Davis Companies acquired in late 2023 for $72.5 million. Davis is removing the old oil tanks and will clean up and prepare the land for the Jupiter project, which would be located across two parcels on either side of Beacham Street. Davis envisions some housing going up on the property as well, but also wants to provide locations for research and industrial uses in the life sciences and clean-tech fields.

“Battery storage, a key element of the energy transformation that’s underway, is a perfect first phase for our climate sensitive development,” said Davis chief development officer Michael Cantalupa.

DeMaria stopped short of fully endorsing the project, citing its preliminary nature, though he said he’s looking forward to learning more.

“The potential for investment of this magnitude and its correlating benefits could make Everett a major player in the climate economy,” DeMaria said in an email.

Jupiter’s project arrives at a time when a number of battery storage developers, such as private equity-backed Flatiron Energy, are eyeing New England. A spokesman for ISO New England said the largest battery energy storage system in New England is in Millinocket, Maine, with 20 megawatts of capacity, although several much larger projects are being lined up, including Jupiter’s and a similarly sized project for Brayton Point in Somerset near Fall River.

“You’re going to see more of these projects,” said Northeast Clean Energy Council president Joe Curtatone, who noted state lawmakers and other officials are weighing potential incentives for the sector. “It’s going to be a huge piece of clean-energy infrastructure that the region needs.”