The largest combined solar and energy-storage project in the U.S. is now online and operating in California’s Mojave Desert.
The sprawling megaproject stretches across 4,600 acres in Kern County and is located on private land as well as the Edwards Air Force Base. It’s the biggest public-private partnership the U.S. Air Force has ever been involved in.
Known as the Edwards & Sanborn project, it was developed by Terra-Gen and built by Mortenson, an engineering, procurement and construction (EPC) contractor. Construction started in the first quarter of 2021 and completion was announced last week. The project includes an astonishing 1.9 million modules from panel-maker First Solar, and 120,720 batteries from LG Chem, Samsung and BYD — which makes it the largest such project in the U.S., according to Mortenson. The equipment is connected with more than 400 miles of wire, according to Brent Bergland, Mortenson’s VP of project development.
As solar makes up a bigger and bigger share of grid power, battery storage is needed to soak up surplus daytime energy and make it available for use later in the day. That’s why solar facilities are increasingly co-located with battery plants: Photovoltaics plus storage is the leading hybrid renewables combination.
This particular project has a generating capacity of 875 megawatts from solar along with 3,287 megawatt-hours of energy storage.
The project provides power to more than 10 customers or “offtakers” including Pacific Gas & Electric, Southern California Edison, the city of San Jose, the Clean Power Alliance and Starbucks. The offtake contracts with Terra-Gen, which will retain ownership of the project and operate it, are a combination of solar-only agreements, storage-only agreements and solar-plus-storage agreements, according to Bergland.