A fledgling San Francisco energy storage company has snagged a big role in moving Hawaii off fossil fuel-generated electricity.

The firm, Plus Power, announced Tuesday that it has been selected by Hawaiian Electric to develop what would be the largest battery system for storing electricity in the state.

Plus Power plans to build a facility capable of holding 565 megawatt-hours of electricity at a Kapolei industrial park connected to Oahu’s electric grid.

The plan is subject to negotiating contract terms with the regulated utility and approval by the state Public Utilities Commission.

If the project is approved, Plus Power anticipates starting construction next summer and operating the facility in 2022.

Bob Rudd, lead developer at Plus Power and a former Tesla and SolarCity executive, said his company, established in 2018, is honored and excited to work with Hawaiian Electric and implement what he called a groundbreaking project.

“We look forward to working closely with all stakeholders to realize this project and deliver its economic and environmental benefits to the people of Oahu,” Rudd said in a statement.

The project is slated for the Kapolei Harborside industrial area on 8 acres of land owned by an affiliate of James Campbell Co.

An estimated cost of the project was not disclosed, in part because the cost is closely linked with how much Plus Power would be paid by Hawaiian Electric to store and distribute electricity, according to Plus Power spokesman Jon Yoshimura.

Pricing for the storage was part of a competitive bidding process that is not yet complete because the deal is still subject to approvals.

Plus Power is working on one of 16 renewable energy projects that Hawaiian Electric tentatively selected earlier this month on Oahu, Maui and Hawaii island involving stand-alone storage and solar energy production linked with electricity storage.

Hawaiian Electric sought bids in August for up to 900 megawatts of renewable energy production plus storage representing the largest and most ambitious push to help the utility increase renewable energy from 25% of power generation now to a mandated 40% by 2030 and 100% by 2045.

The utility said it selected 16 projects but is leaving it up to winners to disclose their plans, in part because each developer is required to have a public discourse in communities where they plan to build their projects.

“Even though these are all solar or low-profile storage projects, we know there’s increasing concern about the location of renewable energy projects,” Jim Alberts, Hawaiian Electric senior vice president for business development and strategic planning, said in a statement earlier this month.

“That’s why we say we need everyone working together — developers, government, communities and Hawaiian Electric — if we’re going to meet our clean energy goals,” he said.

The 16 projects collectively could produce 460 megawatts of solar energy and nearly 3 gigawatt-hours of energy storage on Oahu, Maui and Hawaii island, according to Hawaiian Electric. This would increase solar megawatts on the utility’s systems by more than 50%.

Besides the Plus Power project, the 16 selected projects include two proposed by Hawaiian Electric: a 160-megawatt-hour energy storage system on Maui and a 12-megawatt-hour storage system on Hawaii island.

Three other projects proposed by Hawaiian Electric were not selected, including a battery system next to the utility’s Kahe power plant in Nanakuli capable of storing 810 megawatt-hours of electricity.

The Kahe project was roughly estimated to cost between $200 million and $300 million.

Hawaiian Electric retained independent observers and a technical adviser selected by the PUC to assure that all proposals — including its own — were reviewed fairly and objectively.

The utility said selection criteria included price, location, technology and plans for meaningful community engagement.

“The projects chosen provide the best opportunity for customer savings and realistic timelines for completion so we can keep our clean energy transition on track,” Alberts said.

The Plus Power project is intended to help balance the supply and demand of increased renewable energy that includes power produced from the sun during the day before demand ramps up at night.

Part of the shift from fossil fuel generation to renewable sources includes retiring Oahu’s 180-megawatt coal-fired power plant, owned by AES Hawaii, by September 2022. This plant is the largest single producer of power on Oahu and can meet 16% of peak demand.

Eight solar projects with storage on Oahu are among the 16 renewable energy proposals selected by Hawaiian Electric. These eight projects have a total generation capacity of 287 megawatts. Storage capacity for the eight projects plus the Plus Power project totals 1.8 gigawatt- hours of electricity.

On Maui three solar-plus-storage projects were selected along with one stand-alone storage pro­ject totaling approximately 100 megawatts of generation and 560 megawatt-hours of storage.

On Hawaii island two solar-plus-storage projects were selected along with one stand-alone storage project totaling approximately 72 megawatts of generation and 492 megawatt-hours of storage.