Solar Patent King Boeing Teams Up With Stirling Energy Systems

A little known fact about Boeing: It’s got more solar patents than anyone else in the U.S. (14 solar thermal patents since 2002 as of January, according to cleantech patent tracking law firm Heslin Rothenberg Farley & Mesiti). So sooner or later the defense contractor would want to commercialize ‘em. This morning Boeing says it has teamed up with solar thermal company Stirling Energy Systems to develop Boeing’s high-concentration photovoltaic (HCPV) solar power technology.

High-concentration solar PV technology uses mirrors and lenses to concentrate sunlight onto a high-efficiency photovoltaic cell. The technology provides more power than standard photovoltaic solar panels, and tends to be smaller in scale than the massive solar thermal plants (that don’t use PV) that are being built in the world’s deserts these days.

Boeing started developing the concentrating solar PV tech (dubbed XR700) back in 2007 in conjunction with the U.S. Department of Energy’s Solar Energy Technologies Program. Stirling Energy Systems, which has the exclusive worldwide license to develop, deploy and commercialize the tech, will now use solar cells from Boeing’s subsidiary Spectrolab for the technology, and plans to deploy the systems commercially by 2012.

Stirling already makes utility-scale solar thermal technology based on a stirling engine called the “SunCatcher” solar dish. Stirling engines were invented centuries ago, and can be more efficient and quieter than internal combustion engines and use a closed system of gases to generate power. Most solar thermal technologies, by contrast, concentrate the sun’s rays onto liquid, which powers a turbine.

Earlier this year Stirling, which was founded in 1996, and is based in Phoenix, Ariz., inaugurated its first project that uses the SunCatcher. Called Maricopa Solar, the 1.5MW solar project in Peoria, Ariz. (Maricopa County) uses 60 SunCatchers and sells clean power to local Arizona utility Salt River Project. Later this year Stirling says it will start construction of two much larger solar plants in California — a potentially 900MW plant in Imperial County, Calif. for San Diego Gas & Electric, and a 850MW solar plant in San Bernardino County, Calif. for Southern California Edison.

Stirling Energy has raised $100 million from Dublin, Ireland’s NTR, which in the process took a 52-percent stake in the company. Stirling isn’t the only company turning to stirling engines for solar power. One example is Infinia, which is backed by a gaggle of A-list Silicon Valley-ers, including Bill Gross’ Idealab and Paul Allen’s Vulcan Capital. (Gross will be speaking at our Green:Net conference next month.)

The CEO of Stirling Energy Systems, Steve Cowman, said in a release this morning that adding on Boeing’s concentrating solar PV tech will help the company “[E]xtend our reach into the solar market for future technology deployments with a product that shares many of the SunCatcher’s key differentiating features – scalability, low water use and high-efficiency.”