Solar panels take on roof tile shape for aesthetics
by Candace Lombardi, Jun 27, 2009
Source: Asia.CNet.com
http://asia.cnet.com/crave/2009/06/22/solar-panels-take-on-roof-tile-shapes-for-aesthetics/
Will a better aesthetic tempt more people into going solar? SRS Energy is betting on it. The company has partnered with US Tile, a leading manufacturer of Spanish, slate, and shake roof tiles, to design solar panels with the exact same shapes as their clay counterparts. The result is solar tiles that can be seamlessly integrated with the terra-cotta tiles on your roof. Instead of the solar panels being on your roof, your solar panels are the roof. Instead of consumers going solar as aftermarket adaptation, the Philadelphia-based company hopes that solar will become part of the architecture and building of residences and commercial properties.
BIPV (building-integrated photovoltaics) have been around for a while, but many of them fail to visually blend in with the existing architecture. SRS Energy is trying to improve that by partnering with roofing companies to replicate existing roof tile designs into thin-film solar panel counterparts. The Solé Power Tile system was unveiled at American Institute of Architects 2009 National Convention and Design Exposition this past May at the Moscone Center in San Francisco. On June 15, SRS Energy unveiled one of the first commercial buildings to implement the Solé Power Tile system. The Swiss chalet-like building is Zwahlen’s Ice Cream & Chocolate Company, a family-run ice cream parlor in Audubon, Penn., owned by SRS Energy’s CEO Marty Low.
US Tile’s Solé Power Tile system will begin to be installed in homes this November 2009 by contractors that have taken the company’s Solé certification class, the first of which will be held this July, according to Abby Nessa Feinstein, director of marketing for SRS Energy. The company plans to move into other US and European markets in 2010. The look of the tiles aside, what about solar efficiency? That’s where consumers will have to think about what’s most important to them. The Solé Power Tile system, which is warranted for 20 years to generate electricity at a rate of 80 percent of capacity, incorporates triple-junction amorphous solar cells produced by Uni-Solar.
Cell efficiency for the tiles is between 8 percent and 10 percent, according to Feinstein. That puts it slightly below what others in thin-film photovoltaics have been getting. Global Solar, for example, has said its existing flexible CIGS cells convert about 10 percent of sunlight into electricity and has plans to get to 13 percent to 14 percent soon. It’s also obviously far behind the 20 percent efficiency achieved by efficient traditional silicon solar panels.
Feinstein says the SRS Energy system’s overall efficiency makes up for the difference in sunlight to electricity conversion figures. “If a homeowner bought 4kW of crystalline silicon panels and then 4KW of the Solé US Tiles, they will get 10 to 15 percent more output in terms of a KWh (kilowatt hour) on their electricity,” said Feinstein.
“You have three layers of semiconductor material and so it is essentially less picky about the light it converts into electricity so whereas crystalline starts and stops converting between 10am and 4pm, our tech will wake up earlier and work later. It converts a larger spectrum of light into electricity. It has less sensitivity to heat, most start to degrade in performance as they get hotter. Our tiles get less hot because the modular is curved and with any curved tile you have air beneath keeping them cooler,” she said.
SRS Energy’s statistics say the average homeowner with Solé Power Tiles can get 860 kilowatt hours per square foot annually living in an area with “5.8 peak sun hours” per day.