Hawaiian Electric to Begin Construction of Standalone Battery Energy Storage System on Maui

Hawaiian Electric will begin construction in January on Maui’s first large standalone load-shifting battery energy storage system as part of its transition to increased use of renewable energy and efforts to reduce carbon emissions. The Waena battery energy storage system (BESS) is intended to support the planned retirement of four generating units at the company’s Kahului Power Plant.

The Waena BESS was approved by the Public Utilities Commission in December 2023. The grid-connected system will have a capacity of 40 megawatts and 160 megawatt-hours and will be located on company-owned property along Pulehu Road in Central Maui. The project is part of the company’s broader plans to reduce its carbon footprint and increase the use of renewable resources, with a stated goal of generating 100% of electricity from renewable sources by 2045. Currently, 41% of Maui County’s electricity comes from renewable resources.

The Waena BESS is expected to come online by 2027. It will be connected to the Waena Switchyard and is designed to store and dispatch energy from large-scale renewable resources, including solar and wind, as needed.

The Waena Switchyard and Waena BESS are part of the planned process to retire the four steam-generating units at the Kahului Power Plant, which currently provide power and system stability on Maui’s transmission system.

Hawaiian Electric is also pursuing replacement generation resources through additional large-scale renewable energy and battery projects on Maui. To date, four contracts for variable and firm renewable energy and associated battery projects have been approved by the Public Utilities Commission and are in various stages of negotiation with the company.