The Dish on Stirling Solar Power

The Stirling Engine, patented by Reverend Dr. Robert Sterling in 1816, is a simple self-contained engine which heats a gas to move a piston. Solar company Infinia's satellite dish-shaped design will concentrate the sun's rays onto a collector on the engine, providing the necessary heat. The simple nature of the Stirling assures that maintenance costs will be minimal. At 14 feet, the dish can spit out 3 kilowatts.

The technology appears to compare well with photovoltaic panels. The company claims that its product achieves 24% efficiency, compared to the 12 -15% of standard solar panels. The dish shape could also be a big space saver over flatter designs. The company says their device could produce electricity 20-30% cheaper than photovoltaics as well. Units will be priced at around $20,000.

This sun catcher may be greener than others too. Since it is made from materials like steel, copper, aluminum, and glass, it avoids the heavy metals and nasty byproducts associated with other solar panel materials and can be completely recycled when it's retired.

Infinia has been putting Stirling engine technology to use for 20 years while working for the likes of NASA, Lockheed Martin, and the National Renewable Energy Laboratory.

Infinia, which recent received a $50 million investment, appears to have a bright future, but the company is already playing catch up. Stirling Energy Systems which has similar technology for concentrating solar power using a Stirling engine, last week recorded 31 percent energy efficiency in a test done in conjunction with the Sandia National Lab.