ZenithSolar Chief Executive Officer Roy Segev said conventional solar panels produce electricity from sunlight with less than 15% efficiency and can cost more than double per kWh.
With billions of dollars being spent in global green stimulus plans, energy firms worldwide are racing to develop more efficient environmentally friendly technologies.
ZenithSolar says that in highest conditions, its system can generate electricity and hot water at a cost to consumers that can compete with fossil fuels without government subsidies.
Ken Zweibel, director of the Institute for Analysis of Solar Energy at George Washington University, said he saw some shortcomings.
The reason the running costs are low, Ken said, is as the Zenith system produces mostly thermal energy in hot water, rather than more precious electricity. He also said all solar cells lose efficiency when operating at such hot temperatures.
Ken added that the joint output of high-efficient electricity and its hot water by-product is a new variation that should work well in regions with ample sunlight.
It’s a marriage of convenience as much as an improvement, said Zweibel, who has not examined the system first-hand but has seen technical data released by ZenithSolar.
The company’s solar field takes up a half-acre lot at the edge of a kibbutz in central Israel. 16 units, each with two 11-square-meter (110-square-foot) dishes, harvest sunlight in a pilot project that will be unveiled on April 26, 2009.
The dishes have about 1,200 small mirrors that concentrate sunlight hot enough to burn through metal on a four-inch (10 centimeters-) square panel of photovoltaic (PV), or solar, cells made from a special material.
The idea is to replace large areas of PV panels with large areas of cheap glass and concentrate the light onto a very small amount of PV material, said ZenithSolar’s chief scientist, David Faiman.
Each dish can produce the same amount of electricity as 200-square-feet (19-square-metres) of conventional PV panel, Faiman said.
About a third of the highest energy produced at the pilot, some 70 kilowatts, is electricity. That is sufficient for around 30 houses. The remaining, around 140 Kw, is heat transferred into water, which doubles as a coolant, to be used by the community.
ZenithSolar said that each unit, producing 15 kW of combined electric and thermal output, has a total cost of about $29,500 and can operate for 15 years. It plans to develop smaller units that can be installed in the backyard or on house rooftops by the end of 2010.
