One of the busiest booths at the 2011 Solar Power International show in Dallas last year was SunPower's unveiling of its low-concentration PV product. The efficiency-leading solar firm actually began as a concentrator company back in 1985.

SunPower just announced the first commercial deployment of its C7 low-concentration PV tracker.

SunPower, Salt River Project and Arizona State University are building a 1-megawatt, low-concentration photovoltaic power plant at ASU's Polytechnic campus in Mesa, Arizona.

SunPower claims its C7 Tracker has up to a 20 percent lower levelized cost of electricity (LCOE) than competing technologies. SunPower did not clarify whether those competing technologies were other low-concentration PV (LCPV) or fixed flat-plate solar panels or panels on trackers. The firm did maintain that the C7 tracker provides "the lowest levelized cost of electricity for utility-scale solar power plants available today." SunPower also said that "a 400-megawatt C7 Tracker power plant requires less than 70 megawatts of SunPower solar cells."

The concentrator would effectively allow the company to increase the power output of its utility-scale solar plants at a time when gaining efficiency the old-fashioned way is becoming more challenging. SunPower will soon mass-produce monocrystalline solar cells with an efficiency rating of more than 23 percent, and the company has demonstrated new cells in the lab that can hit 24 percent.

One unanswered question is the impact of the increased heat and "hotspots" on the silicon solar cells. It also remains unclear why SunPower would be looking at alternative architectures at this juncture in its corporate career in this difficult market.

Here's a picture of SunPower's C7 tracker at SPI.


Here's a video of the SunPower tracker:


Skyline Solar won a $1.85 million contract from the Department of Defense for deployment of its low-concentration PV solar power plants at two domestic military sites. Skyline claims that its 14-suns concentrator "delivers an LCOE of less than ten cents per kWh in sunny climates."

Skyline's concentrators (see picture below) are also being deployed on what will be the largest CPV plant in Latin America, located in Durango, Mexico and totaling 500 kilowatts.



Low-concentration solar systems and components like those of SunPower, Skyline, or Solaria, Zytech, Banyan, and others have the benefit of being able to ride the silicon cell cost curve down as the price of that commodity continues to plunge. But the unique design of LCPV still has to compete with the massive flat panel supply chain as that industry continues to scrub out hardware costs and soft costs. What's more, aggressive estimates of LCOE by Skyline and SunPower have to be taken with a grain of salt when the product has accumulated only a scant amount of field data.