Israeli ingenuity and invention could potentially produce a global revolution in solar electricity generation. The solar energy market has generally been divided into photovoltaic (PV) solar power and large-scale solar thermal power plants - until now. Aora Solar, part of the E.D.I.G. Group, has developed a small-scale hybrid solar thermal power plant which could open up a whole new market.
Both PV and regular solar thermal power need vast tracts of land to accommodate all the mirrors or heliostats they require. Aora's new model requires just half an acre of land to produce 100 KW, enough to power 50 homes. By solar standards, that's not a great deal of electricity. Yet there are several advantages to Aora's system, COO Yuval Susskind told The Jerusalem Post ahead of the Eilat-Eilot International Renewable Energy Conference and Exhibition at the beginning of February.
"Aora's model has four advantages. It's modular, it's hybrid, it can run on alternative fuels and it offers all of those options in one base package," he explained. What's the secret behind the new technology? Pairing a proprietary solar concentrator with a micro-gas turbine instead of a steam turbine. Conventional solar thermal power, such as that produced by Brightsource/Luz II or Soleil, relies on heated water turning into steam which is then used to power a turbine. However, steam turbines are only efficient when producing many megawatts (MW), which also requires a great deal of land. Aora uses a micro-gas turbine which is effective at less than one MW and requires far fewer heliostats (30) to produce 100 KWs.
"A small, modular base unit which doesn't take up very much space means that you can plug it straight into the nearest electricity line. You don't need to run new lines or install new components to handle the flow. In addition, you can link several units together around a village, say, to produce enough power," the South African-raised Susskind said. Each base unit is comprised of one 30 meter high tower housing the concentrator, micro-gas turbine and 30 heliostats.
In addition to modularity, the gas turbine also allows for 24-hour energy production.
"During the day, the turbine runs on thermal power from the sun. At night, it can run on anything else, including natural gas, bio-fuel, bio-diesel, etc," Susskind told the Post. That means it's a self-contained, reliable power generation system that works around the clock. At around $500,000 per base unit, it's also cheaper than its bigger PV or solar thermal cousins.
The breakthrough technology was developed in conjunction with the Weizmann Institute and Rotem Industries. National Infrastructures Minister Binyamin Ben-Eliezer (Labor) signed the first license for solar thermal electricity production for Aora last week. The company hopes to have its first commercial base unit producing electricity sometime this month at Kibbutz Samar outside Eilat. A prototype unit was tested in China in 2006.
While Aora's modular units could provide a good solution for southern Israel's energy needs, the feed-in tariff for solar thermal power had been set too low to make it profitable, according to Susskind.
"Israel must not miss this opportunity to develop its own solar industry, and to become a testing site for cutting edge solar technologies," Susskind vehemently insisted. "All we want is the same tariff PV was given [NIS 2.04 for household units up to 50KW]."
While Aora will certainly seek out sunny markets beyond Israel's borders, Susskind said he saw it as almost a Zionist obligation to help Israel move toward more renewable energy.
