Israeli energy startup Zenith Solar is pioneering a "concentrated solar power" method that is up to five times more efficient than standard technology
Rooftops all over Israel look strikingly similar: More than 1 million households in the nation of 7.1 million people have solar panels that produce hot water—a relatively simple technology that gained popularity after the 1973 Arab-Israeli war, when oil prices shot up sharply. As of the early 1990s, all new residential buildings were required by the government to install solar water-heating systems.
Yet despite Israel's sunny climate and early lead in solar heating, it has been slow in adopting more sophisticated solar technologies that produce electricity from sunlight. Now, with oil hovering above $100 a barrel, a local startup hopes to build on the country's early embrace of sun power to carve out a new clean-energy business.
Zenith Solar, based in Nes Ziona near Tel Aviv, is a pioneer in a new type of solar energy that uses mirrors and lenses to focus and intensify the sun's light, producing far more electricity at lower cost. Compared with traditional flat photovoltaic panels made of silicon, this so-called concentrated solar power technology has proved in tests to be up to five times more efficient. That puts it on the verge of being competitive with oil and natural gas, even without government subsidies.
A Boost to Israel's Energy Supply
"Our goal is to utilize every suitable roof, backyard, and open space in Israel to turn households, hotels, and factories into net producers of electricity and thermal heat," says Roy Segev, the founder and chief executive of Zenith Solar. Founded in 2006, the startup has raised $5 million from a handful of private investors in Israel and the U.S. Now it's trying to raise an additional $10 million to $15 million to cover the cost of commercializing its technology.
The opportunity is compelling. Israel's National Infrastructure Ministry estimates solar panels for water-heating already satisfy 4% of the country's total energy demand. With technology like Zenith Solar's widely installed, the figure could jump to more than 16%—a big boost for a country now almost totally dependent on imported energy.
Zenith bought the rights to the solar technology from Ben-Gurion University and Germany's Fraunhofer Institute. A joint Israeli-German research team from the two organizations designed a working prototype, which consists of a 10-sq.-meter (107.6-sq.-ft.) dish lined with curved mirrors made from composite materials. The mirrors focus the sun's radiation onto a 100-sq.-centimeter (15.5-sq.-in.) "generator" that converts light to electricity. The generator also gives off intense heat, which is captured via a water-cooling system for residential or industry hot-water uses.
Tested over the past few years at Israel's National Solar Center in the Negev desert, the prototype achieved astounding results: A concentration of solar energy that was more than 1,000 times greater than standard flat panels.
Avoiding Costly Panels
One of the biggest advantages of Zenith Solar's approach, especially in today's market, is its limited use of polysilicon. Skyrocketing global demand for traditional photovoltaic panels has led to a worldwide shortage of the material and lifted prices tenfold in the past four years.
"Photovoltaic material accounts for 80% of the cost of standard systems," says David Faiman, chief scientific officer at Zenith, and a 30-year solar-energy veteran who was part of the development team. "Our technology succeeds in reducing this to less than 10%, while at the same time obtaining very high efficiency."
After further refining the technology, Zenith plans in the coming months to take its first major steps toward commercialization. Two large-scale test installations are planned for this summer at a kibbutz and a factory. The company will put 86 of its 7-meter-high dishes on an acre of land at Kibbutz Yavne to provide the community of 250 families with more than a quarter of their energy needs. The second project will replace fuel oil used to produce heat at a large chemical plant in central Israel.
Once these projects are operational, Zenith plans to start commercial sales in Israel in 2009 and then to go abroad, says CEO Segev, a 46-year-old entrepreneur who is one of the growing number of Israel's high-tech elite getting involved in renewable energy. The company is already planning a range of products that would be adapted for household, commercial, and industrial users—and even entire neighborhoods or communities. The price tag for a home-size unit is likely to be less than $20,000.
Zenith sees particularly large market opportunities in the U.S., Spain, Italy, Greece, India, and China. "In California alone, there are 6.9 million private homes that could potentially produce most or all of their own energy," Segev says. To compete abroad, the startup aims to link up with major energy players in other countries.
Until now, the Achilles' heel of solar panels has been the low efficiency of the cells that convert the sun's energy into electricity. Dozens of companies and research labs around the world have toiled to make photovoltaic competitive with other energy technologies, but so far, the best systems have an efficiency level of no more than 10%. As a result, solar panels are heavily subsidized by governments around the world.
Making Solar Energy Competitive
That's not a viable long-term solution. "Photovoltaic can't continue to exist on subsidies or it will remain a marginal form of energy," says Amit Mor, CEO of Eco-Energy, an Israeli energy consulting firm. Electricity produced by photovoltaics currently costs about 30¢ to 40¢ per kilowatt-hour. That's two to three times the average cost of power made from conventional fuels in the U.S. and Western Europe.
Concentrated solar power offers the hope of changing that equation. "The first generation of our technology should be capable of harnessing about 70% of the solar energy that hits the dish to produce electricity and thermal heat," says Faiman. With that type of efficiency, Zenith Solar says the cost of producing energy with its technology is close to that of conventional fuels.
It's too early to know whether Zenith Solar's technology will catch on the way solar water-heating did in Israel. But with the growing concern for global warming, and oil prices at record highs, the timing of the startup's entry into the market couldn't be better.