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Posted on EVANNEX on October 06, 2022, by Iqtidar Ali

The state of Hawaii is moving toward sustainable energy as it ends operations for the last coal-powered electric power plant at Oahu's Campbell Industrial Park.

Tesla Megapack plant in Oahu, Hawaii.

Above: Aerial view of the under-construction Tesla Megapack battery energy storage system project in Hawaii. Electric Photo: Plus Power LLC

Tesla's Megapack battery system is stepping in to fulfill the state’s power requirements, following the end of a 30-year deal on September 1 between Hawaiian Electric and AES Corporation to provide coal power (via Hawaiian Electric).

As an alternative to the energy gap left behind by the coal power plant, Plus Power LLC  is using Tesla Megapacks to build a large battery energy storage system (BESS) in the state of Hawaii.

This sustainable energy project is named Kapolei Energy Storage (KES). KES is one of the world’s largest battery energy storage systems, featuring a capacity of 565 MWh. It will be charged using a 156 MW solar energy farm.

State-owned Hawaiian Electric estimates the completion of the KES project in the first half of 2023. According to the state’s electricity supply company, 9 BESS projects are scheduled to go live by 2024 on the island of Oahu alone (FAQ PDF by Hawaiian Electric).

“Last coal shipment arrived in Hawaii at the same time as Tesla Megapack batteries that will enable 24/7 sustainable energy,” Tesla CEO Elon Musk said in a recent tweet.


The retired AES coal power plant was the largest greenhouse gas emitter in the state of Hawaii and was alone responsible for releasing 1.5 million metric tons of carbon dioxide annually (Source: Hawaiian Electric press release).

The capacity of a single Megapack battery is 3 MWh, so to set up a 565 MWh energy storage system (BESS), around 189 Megapacks will be required on the KES project site.

Megapack stores energy for the grid reliably and safely, eliminating the need for gas peaker plants and helping to avoid outages. Each unit can store over 3 MWh of energy—that’s enough energy to power an average of 3,600 homes for one hour.

Source:Tesla Megapack official web page.

With the help of Tesla’s Megapacks, Hawaii will be able to sustainably handle peak-hour electricity demand.

Inside of a Tesla Megapack

Above: Internal view of a Tesla Megapack battery storage module, the integrated inverter can be seen in the center of the unit (Source: Tesla, Inc.).

Megapack delivers more power and reliability at a lower cost over its lifetime. Each battery module is paired with its own inverter for improved efficiency and increased safety.

Tesla Megapack web page.

Interestingly, like Tesla’s electric vehicles, the company’s energy storage systems (the Megapack, Powerpack and Powerwall) also get periodic over-the-air software updates. This means that the product automatically gets better over time as new software is downloaded — without any extra cost to the customer.

In the past, Tesla also built a Megapack sustainable energy storage system at PG&E's Moss Landing, California site.


Written by: Iqtidar Ali. An earlier version of this article was originally published by Tesla Oracle. Revised update edited by EVANNEX.

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