This story was originally published by Canary Media. Hawaii shut down its last coal plant on September 1, 2022, eliminating 180 megawatts of fossil-fueled baseload power from the grid on Oahu. This was a crucial step in the state’s first commitment to cease burning fossil fuels for electricity by 2045. The move raised the question of how to maintain a reliable grid while switching to a portfolio of renewables. The answer is a gigantic battery, unlike any built before.
The Kapolei Energy Storage system began commercial operations before Christmas in a remote industrial location on Oahu. This battery contains 158 Tesla Megapacks and is designed to absorb and deliver clean, renewable power with a 250-millisecond response time. It matches the old coal plant’s power output and provides grid services, such as stabilizing functions, and the ability to restart the grid in the event of a disaster.
The battery aims to replace clean, renewable energy from the coal plant and reduce curtailment of renewables by up to 69%. It is also the first large-scale battery capable of combining peak capacity, frequency response, synthetic inertia, and grid-rebooting tasks. The project marks a significant step in transitioning critical grid functions from fossil-fueled plants to clean energy plants and is a model for a reliable clean-energy grid.