Energy storage facility developer Hydrostor has selected Kiewit Engineering Group to advance Front End Engineering and Design (FEED) studies for the 500MW Willow Rock Energy Storage Center in California, the US.

According to the company, the move will mark a key step in the development of Hydrostor’s Advanced Compressed Air Energy Storage (A-CAES) technology in North America.

Hydrostor CEO Curtis VanWalleghem said: “Hydrostor continues to reach important milestones at Willow Rock, and we look forward to working with the world-class engineering and construction teams at Kiewit to advance this critical clean energy project.”

Located in Eastern Kern County, Willow Rock is an A-CAES project that will provide up to 500MW of new electrical capacity.

It will store excess power from California solar and wind projects and will supply it during high demands.

The project is designed to meet energy requirements for up to 400,000 homes over eight hours.

During peak construction period, Willow Rock is expected to create around 800 jobs.

Kiewit Power Engineers president Kevin Needham said: “Kiewit remains committed to engaging in the clean energy transition and recognizes that LDES solutions like A-CAES are a critical component of grid modernisation.

“We look forward to commencing work on Willow Rock, which has the potential to abate significant emissions and provide a reliable, sustainable energy source for many decades.”

VanWalleghem added: “Our global teams are paving the way towards achieving aggressive net-zero goals. Willow Rock will be capable of eliminating the equivalent of roughly 120,000 cars off the road every year over its 50+ year project life.”

Earlier this year, Goldman Sachs made a $250m investment in Hydrostor.