Tesla to replace backup diesel generators with 200 battery systems on the US island of Nantucket

National Grid, Nantucket’s grid operator, has announced the installation of 200 of Tesla’s unique ‘Powerpack' battery systems to the island in order to reduce reliance on backup diesel generators and add capacity.

Nantucket, a small island approximately 30 miles off the Massachusetts, is connected to the US mainland grid through two submarine cables, which often perils power black-outs.

At the moment, 6MW of backup diesel generators secure the supply of electricity to the 10,000 permanent residents and to an increasing number of visitors.

National Grid explained that due to increased electricity demand, the island considered the addition of a third submarine cable, especially as the diesel generators are reaching their de-commissioning time.

Instead, National Grid decided to install a 6MW battery energy storage system (BESS), which will offer 48 MWh of power, and only one new diesel generator.

The new battery system will not only reduce reliance on expensive diesel backup generators but will also help reduce peak demand and stabilise the grid.

Rudy Wynter, President and COO of National Grid’s FERC-regulated Businesses said: “The battery energy storage system provides a very efficient and effective solution to two major energy challenges facing the island. Our customers, communities, and policymakers look to us to deliver innovative solutions like this to help advance our clean energy future”.

Lauren Sinatra Energy Coordinator of the Town of Nantucket welcomed the innovative energy storage solution and said: “We are confident that the proposed project, combined with targeted energy-saving programs and other planned electric infrastructure upgrades, will play a transformational role in meeting Nantucket’s near- and long-term energy needs”.

National Grid expects that with the new batteries the need for a third cable will be delayed for 15 to 20 years beyond the current 12-year forecast.

The 200-Powerpacks order is one of Tesla’s biggest energy storage projects to date.