SkyFuel heats up solar thermal power race

Update on October 13, 2008 6:30 a.m. PT: Corrections to the SkyFuel's relationship to NREL and it's projected cost of delivered electricity.

Even with the teetering economy, solar companies are bullish that tapping free energy from the sun is a solid financial move.

SkyFue on Friday is hosting an event to unveil its solar power plant system: a parabolic trough made from reflective plastic. Colorado Gov. Bill Rittner will speak at the event, held at SkyFuel's research center in Arvada, Colo.

SkyFuel's parabolic trough, made with reflective plastic rather than mirrored glass, a design which it says lowers the overall cost.

(Credit: SkyFuel)

Parabolic troughs have been around for decades and are considered the incumbent technology in concentrating solar thermal power plants, which are suited for hot desert climates like in Spain and the U.S. southwest.

Reflective troughs concentrate sunlight onto a liquid which is converted to steam, which turns a power generator.

SkyFuel's enhancement on the basic shape is a trough that uses silver encased in plastic, rather than mirrored glass. Although silver is certainly an expensive material, using plastic cuts down on the overall cost, according to Chris Huntington, vice president of business development at SkyFuel. The company's founder tested the designs extensively with the National Renewable Energy Lab in Colorado.

He said that the cost of an installed solar power plant using its equipment is about 25 percent less than existing parabolic troughs.

The company estimates that it can profitably deliver electricity below the concentrating solar power benchmark of 15 cents per kilowatt-hour. That's the price of other solar thermal technologies, but still more than a natural gas or coal power plant.

Using a solar trough installation at an existing power plant, where there would not be the need to purchase a steam turbine would lower the cost significantly, Huntington said.

Several solar thermal companies have sprouted up in the past five years, with different designs such as Ausra's Fresnel lens glass reflectors or eSolar solar power tower.

Demand is driven by state-level renewable portfolio standards. Utilities in California, for example, need to purchase 20 percent of their electricity from renewable sources by 2010.

Huntington said the company expects to have a small installation of its SkyFuel system--on the order of 2 to 10 megawatts in size--in the next year and then larger installations after those pilots.

Having a less cutting-edge design than other firms is an advantage in a tight funding market, Huntington said.

Click on the image to see a photo gallery of different concentrating solar technologies.

(Credit: Ausra)

"The cost of borrowing is going up everywhere and there will be a tighter credit market. But if any money is going to be spent on CSP (concentrating solar power) plants in the near future, I think it's going to be on tried-and-true systems like the parabolic trough," he said.

The company is already working on the second generation product that will include storage through a Department of Energy grant. It probably won't be commercially available for at least three years, Huntington said.

Rather than heat up oil or hot water, the parabolic troughs will heat up tubes of molten salt. That salt can be stored to make electricity even after the sun goes down.