Inhabitat has a look at an interesting window surface incorporating concentrating solar PV technology - CASE Solar Power Glass Energizes Any Building Facade.
Solar engineers have long sought to develop an energy-generating glazing that is as capable of producing power as it is easy on the eyes. The feat may just have been accomplished by The Center for Architecture Science and Ecology (CASE), who have developed a concentrating solar system that is not only modern and attractive but extremely efficient and cost effective. The system is made up of rows of pyramid-shaped glass receptors that move with sunlight throughout the day, magnifying the incoming light and capturing it in a small photovoltaic cell located in the center of each pyramid.
CASE’s receptors can be fitted to existing buildings or built into new designs. The concentrating solar cells are strung on wires with tracking mechanisms that turn the receptors in the direction of the sun throughout the day. Since they are made from glass they are transparent and allow light to pass through windows, which makes them perfect for adding solar power to building facades while maximizing available daylight.
The glass pyramid shape actually serves to magnify light and increase the natural lighting inside a building while decreasing the need for artificial light. The design is also meant to capture thermal energy trapped inside the glass pyramids that is not converted into electricity to be used for heating and cooling systems.