Tesla has recently constructed a solar energy installation on the island of Kauai in Hawaii.

The Kauai solar energy project is made up of a 52 megawatt-hour battery installation and the accompanying 13 megawatt SolarCity solar farm.

Kauai Island Utility Cooperative (KIUC) cooperated with Tesla on the project, and the two interests believe that the project will cut fossil fuel usage by 1.6 million gallons a year.

There are no natural gas pipelines or rail lines to move coal on Kauai, and to compensate many residences and businesses have utilized solar power, reducing the need to use fossil fuels during the day. However, at night the generators turn on. Kauai and similar islands have traditionally met their energy needs by shipping in barrels of diesel fuel. Tesla is looking to change that with the new solar installation and energy project.

A report on the project says that the KIUC project makes use of Tesla’s Powerpack 2 battery system, which is produced at Tesla’s Gigafactory in Nevada. KIUC contracted with Tesla to purchase the electricity needed, rather than purchasing the solar panels and batteries from Tesla. KIUC is in a 20-year contract with Tesla to purchase the energy generated by the solar energy project for about 13.9 cents per kilowatt hour.

The Kauai project is Tesla’s first major solar/storage project since they acquired SolarCity last year for 2.6 billion dollars.

“[Tesla] Will work with energy providers around the world seeking to overcome barriers in the way of building a sustainable, renewable energy grid of their own,” says Tesla in the report.

Tesla’s CEO Elon Musk says he envisions stationary storage as being as big at the car business long term.

“[Solar storage facilities] actually have a growth rate probably several times that of what the car business is per year. The growth in stationary storage is really under appreciated. That’s a super-exponential growth rate,” Musk said.