The US set a goal to slash the cost of long-duration storage by 90% within a decade in the second of the Department of Energy’s (DoE) ‘Earthshot’ targets.

The programme announced by energy secretary Jennifer Granholm aims to boost development of grid-scale technologies that can store energy for longer than 10 hours – a role currently mostly met by pumped hydro – to complement shorter-duration battery systems, said the DoE.

“We’re going to bring hundreds of gigawatts of clean energy onto the grid over the next few years, and we need to be able to use that energy wherever and whenever it’s needed,” said Granholm.