SunPower, a Silicon Valley manufacturer of high-efficiency solar cells, panels, and systems, announced Monday the debut of its its new SunPower E19 Series solar panels, a product lineup that offers an efficiency of 19 percent or greater.
The efficiency figure measures how great a percentage of the sunlight that hits a solar panel is actually converted into usable electricity. The higher the efficiency, the cheaper the cost of using solar energy.
Some companies have reached up to 42 percent efficiency in testing their products. Others have claimed even higher percentages in the lab. But most commercial silicon solar cells average in the 15 percent range.
The E19's panels achieve a higher efficiency by using 3 percent more surface space per cell and by employing an antireflective coating that can capture greater amounts of off-angle light, explained San Jose, Calif.-based SunPower. The coating helps generate more energy per watt than a conventional solar panel. The combination of the coating and larger cells also offer a darker and more aesthetic look to the panels, the company said.
The E19 line includes a 318-watt, 96-cell solar panel with an efficiency of 19.5 percent and a 238-watt, 72-cell solar version with an efficiency of 19.1 percent.
Besides the new E19 Series, SunPower will continue to offer its E18 product line, offering 18 percent or greater efficiency. The E18 lineup includes 96-cell and 72-cell configurations that range in power from 305 watts to 225 watts. The E19 product line will be available to both residential and business customers in North America and Europe starting in the third quarter of 2010.