Bringing Sunlight Inside

Mechanical Engineers Create High-tech Solar Panels

May 1, 2007 - Science Daily

Photovoltaic panels have a new design: concentric circles that focus the sun's rays on miniaturized modules. Having the panels automatically sense sunlight and turn towards it also makes these high-tech solar cells more efficient.

Solar energy technology is advancing daily. Now, a new, high-tech system is working to efficiently harness the power of the sun and drastically reduce harmful carbon dioxide emissions.

Today, there are more than 76 million residential buildings and nearly 5 million commercial buildings in the United States. Combined, they use two-thirds of all electricity consumed in the United States and produce 35 percent of all carbon dioxide emissions.

Anna Dyson, an architectural scientist from Rensselaer Polytechnic Institute in Troy, New York, is leading the way to make solar energy a real alternative to pollution-emitting fossil fuels. Her system contains rows of thin lenses that track the sun's movement. Sunlight floods each lens and is focused onto a postage-stamp sized, high-tech solar cell. Dyson says, "Really, what we want to do is be capturing and transferring that energy for usable means."

Conventional solar systems are about 14 percent efficient. This system has a combined heat and power efficiency of nearly 80 percent. "What they're doing is very efficiently capturing and transferring that light into electricity and the solar heat into hot water," Dyson explains.

"We basically have a system that can sense where the sun is at any time, and then the modules will basically be facing directly perpendicular to the incoming sun rays," she says. The lenses will be nestled between window panes and all of the pieces will be made of glass.

Michael Jensen, Ph.D., a mechanical engineer from Rensselaer Polytechnic Institute says reducing dependency on fossil fuels is critical. Dr. Jensen explains, "We use fewer fossil fuels, then we are going to put less CO2 into the atmosphere. We are going to decrease the effects on global warming."

This system will also lower the lighting needs of buildings, as it will provide usable light inside. It could supply as much as 50 percent of the energy needed for a building to operate. The system is set to be installed in the Center for Excellence and Environmental Energy Systems in Syracuse, New York, in 2008, and in the Fashion Institute of Technology in New York City by 2009.