Arizona’s Salt River Project has selected Germany’s CMBlu to deploy a 5 MW, 10-hour storage project that will soak up solar energy and discharge it overnight, the utility announced Thursday.

The pilot project will “supplement SRP’s power system helping provide stored power for longer periods, especially in times of fluctuating, high energy demand,” SRP CEO Jim Pratt said in a statement. “It will be a helpful addition to SRP’s significant number of renewable resources and storage projects, which generally only store energy for up to four hours.”

The project, dubbed Desert Blume, will utilize non-lithium technology and be located at SRP’s Copper Crossing Energy and Research Center in Florence, Arizona. CMBlu’s battery technology utilizes a “non-flammable proprietary mixture of solid electrolyte and water-based electrolytes with high energy density and performance,” the companies said.

SRP will be the first U.S. electric utility to implement CMBlu’s batteries at this scale, the parties said. The storage company in July announced the first deployment of its system with Burgenland Energie in Austria, and is also working with WEC Energy in Milwaukee.

The Electric Power Research Institute will support performance monitoring of the project and “help validate the real-world performance of the technology in Arizona’s hot and dry climate,” SRP said.

Construction on Desert Blume is expected to begin in early 2025, with the project operational in December 2025.

The pilot is the third part of a multi-phase development of the Copper Crossing research center. The first phase will add two natural gas turbines with a total output of less than 100 MW, and the second will add a utility-scale advanced solar generation facility with a capacity up to 55 MW, according to SRP.

Electricity demand in Arizona is on the rise and in February SRP issued an all-source request for proposals for at least 500 MW. The utility is seeking to bring at least 200 MW online as early as May 2026, and at least 300 MW to be online by May 2027.