The Kapolei Battery Energy Storage System is an 185,000kW energy storage project located in Kapolei, Oahu, Hawaii, US. The rated storage capacity of the project is 565,000kWh.

The electro-chemical battery energy storage project uses lithium-ion as its storage technology. The project will be commissioned in 2022.


The Kapolei Battery Energy Storage System is being developed by Plus Power.

The key applications of the project are load shifting, frequency regulation, grid reliability and resiliency.

Contractors involved

Plus Power is the developer of Kapolei Battery Energy Storage System.

Additional information

The 185 MW / 565 MWh battery storage project will provide load shifting and fast-frequency response services to Hawaiian Electric, enhancing grid reliability and accelerating the integration of readily available renewable energy. KES will support the retirement of the AES coal plant, planned for September 2022.


All publicly-announced energy storage projects included in this analysis are drawn from GlobalData’s Power IC. The information regarding the projects are sourced through secondary information sources such as country specific power players, company news and reports, statistical organisations, regulatory body, government planning reports and their publications and is further validated through primary from various stakeholders such as power utility companies, consultants, energy associations of respective countries, government bodies and professionals from leading players in the power sector.