Based in Charlottesville, Virginia, East Point Energy has a 4.1GW pipeline of mid-stage battery storage projects in the US East Coast region.
The privately owned company has also identified additional growth potential beyond its existing pipeline.
The acquisition is intended to help Equinor broaden its range of energy offerings in the US.
The financial details of the deal have not been disclosed.
East Point Energy CEO Andrew Foukal said: “On behalf of the East Point Energy team, I am excited to welcome Equinor as the new owner.
“We look forward to a long and successful relationship developing, owning and operating energy storage projects in the US.”
Equinor Renewables power and markets senior vice-president Olav Kolbeinstveit said: “The acquisition of East Point Energy represents Equinor’s entry into the US power market through flexible assets.
“It will enable Equinor to further unlock the potential we see in the renewables space in the US, capturing value from volatility in the power markets and providing reliable services to the grid.
“The acquisition will provide us with attractive investment opportunities, and the projects will contribute to lifting the return on our renewable portfolio while at the same time lowering the portfolio risk.”
The deal is expected to close in the third quarter of this year.
It comes after Equinor signed an agreement last December to acquire a 45% stake in UK-based battery storage developer Noriker Power.
Under the terms of the agreement, Equinor has an option to acquire a full stake in Noriker Power at a later stage.
Last month, SSE Thermal and Equinor agreed to purchase Triton Power Holdings from Energy Capital Partners for a £341m consideration.