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ZenithSolar, an energy company in Israel, plans to launch this solar farm in April 2009 using new technology it says can produce cheap and efficient electricity while supplying hot water to homes - Source: Reuters
An energy company in Israel plans to launch a solar farm this
month using new technology it says can produce cheap and efficient
electricity while supplying hot water to homes.
As with all solar energy systems, investors and consumers may be
turned off by high initial costs and the need for strong
sunlight.
But if the commercial pilot works, Israeli start-up ZenithSolar
plans to make small units for homes in two years.
ZenithSolar CEO Roy Segev says its energy dish can transform 75% of
the sunlight it absorbs into electricity and hot water, with a cost
of 8.6 cents per kilowatt hour.
Conventional solar panels generate electricity from sunlight with
less than 15% efficiency and can cost more than double per kilowatt
hour.
With billions of dollars being invested in global green stimulus
plans, energy companies worldwide are racing to develop more
efficient environmentally friendly technologies.
ZenithSolar says that in peak conditions, its system can produce
electricity and hot water at a cost to consumers that can compete
with fossil fuels without government subsidies.
Asked about the Israeli company's system, 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, he said, is because the
Zenith system produces mostly thermal energy in hot water, rather
than more valuable electricity.
He also said all solar cells lose efficiency when operating at
such hot temperatures.
But he added that the combined output of high-efficient electricity
and its hot water by-product is a new variation that should work
well in areas 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.
1,000 times sunlight
The company's solar field takes up a half-acre lot at the edge of a
kibbutz in central Israel.
Sixteen units, each with two 11-square-metre dishes, harvest
sunlight in a pilot project that will be unveiled on April
26.
The dishes have about 1,200 small mirrors that concentrate sunlight
- hot enough to burn through metal - on a four-inch 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 generate the same amount of electricity as
19-square-metres of conventional PV panel, Faiman said.
About a third of the peak energy produced at the pilot, some 70
kilowatts, is electricity.
That is enough for about 30 houses.
The rest, about 140 kilowatts, is heat transferred into water,
which doubles as a coolant, to be used by the community.
The company says that each unit, generating 15 kilowatts of
combined electric and thermal output, has a total cost of about
$52,661 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.
