Hawaii has successfully decommissioned its last coal power plant, replacing it with a large-scale energy storage system using Tesla Megapacks.
The Kapālama Energy Storage System, developed by Plus Power in collaboration with Tesla, plays a pivotal role in stabilizing the island’s electrical grid.
“This system is proving to be vital for stabilizing the grid in the future,” stated a spokesperson from Plus Power. The project, which began in 2018, is part of Hawaii’s broader goal of transitioning to 100% renewable energy by 2045.
With 158 Tesla Megapacks on site, the facility has a capacity of 185 megawatts and 565 megawatt-hours, enough to meet 20% of Oahu’s peak electrical demand. The energy storage system ensures that renewable energy fluctuations caused by variable weather conditions—such as sudden cloud cover or changes in wind speed—do not disrupt power supply.
“Despite advancements in technology, the electric grid is more fragile than many realize,” said the spokesperson. “Battery energy storage systems like this one manage fluctuations and keep the grid stable.”
The Kapālama system also has “black start” capability, meaning it can restart the grid during power outages. Local communities, including neighborhood board members and the Honolulu Fire Department, have supported the project.
In a unanimous vote, the project was approved by local authorities. “This is going to be good for Hawaii and all our communities,” said the spokesperson. The project is expected to serve as a model for future renewable energy transitions globally.
Check out Tesla’s video below detailing the historic move over to Megapacks:
