#hawaii

First six Megapacks installed at Hawaiian Electric's 40 MW Waena battery

Hawaiian Electric said on September 21, 2026 that the first six of 54 Tesla Megapacks are installed at its Waena Battery Energy Storage System on Maui, a 40 MW / 160 MWh system it says will be the island's first standalone load-shifting battery and expects in service in 2027; HEI's June 30, 2026 quarterly report lists a guaranteed commercial operation date of November 30, 2026. Final PUC approval came December 22, 2023 in Docket 2020-0132, per the utility's development-team page; HEI's filings put the approved estimate at $82.1 million against $60.0 million in the 2020 application.