Hawaiian utility to balance grid with 565 MWh battery

A large grid-scale energy storage project in Hawaii, featuring Tesla Megapacks, could potentially minimize the curtailment of renewables output.

January 12, 2024 Ryan Kennedy

From pv magazine USA

Plus Power has started operating its Kapolei Energy Storage (KES) facility on Oahu, Hawaii, helping the state in its transition from fossil fuels to solar and wind. 

The KES project adds 135 MW/540 MWh to the Hawaiian Electric grid, with an additional 50 MW/25 MWh of additional “fast frequency response” to support grid stability.

The advanced battery has “virtual inertia” to replicate the power-smoothing function of a conventional spinning turbine. It has “black start” capabilities, which supports grid recovery in the event of a blackout. 

“It’s the first time a battery has been used by a major utility to balance the grid: providing fast frequency response, synthetic inertia, and black start,” said Brandon Keefe, executive chairman, Plus Power. This project is a postcard from the future – batteries will soon be providing these services, at scale, on the mainland.”   

Located on 8 acres of industrial land on the southwest side of Oahu, the project is comprised of 158 Tesla Megapack 2 XL lithium-ferro-phosphate batteries, each about the size of a shipping container. 

The battery can serve as a grid “shock absorber,” serving a role normally performed by combustion-powered plants. It can respond to grid signals in 250 milliseconds, far faster than the several minutes that conventional power plants take to fire up. 

“Energy storage technology that responds quickly to constantly changing conditions is an essential tool for us to use to manage the grid and operate it as efficiently as possible,” said Ji