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Energy Commission's Investment Helped Energize Battery Storage Company

Primus received a $95,000 research grant to build and install a low-cost, energy storage battery system

Primus Power


Primus Power CEO Tom Stepien was asked recently what chance his company would have had in successfully developing its battery storage system without support from the Energy Commission. His response was "darned near zero."

In 2005, Primus received a $95,000 Energy Commission research grant to build and install a low-cost, energy storage battery system for utility substation backup power. A few years later, the Hayward-based company received a $1 million grant from the Energy Commission to field test a 25-megawatt flow battery system.

Both were a success, and since then, Primus has experienced tremendous growth and seen global interest in its products. It now has a workforce of 50 employees, holds 34 patents and has 26 additional patents pending.

The company has also secured $94 million in venture capital financing from a variety of investors and $20 million in federal grants from the U.S. Department of Energy's Advanced Research Projects Agency-Energy and the U.S. Department of Defense.

Primus' energy storage technologies and products are operating at Marine Corps Air Station Miramar in San Diego, and sites in Rancho Cucamonga and Bellevue, Washington. Microsoft announced a pilot program with Primus and other energy storage companies to evaluate the performance of long-duration flow batteries at Microsoft's data centers.

Stepien thanked the Energy Commission for its support in a note: "Your funding has greatly assisted Primus. Thank you. Together, we are creating new jobs, helping California achieve its energy goals and creating a cleaner, more reliable and more efficient electric grid."