Windsor Locks, Conn.-based Hamilton Sundstrand is bringing salt to the desert.

The company announced plans to work with Santa Monica, Calif., private equity firm US Renewables Group to commercialize a concentrated solar power system that uses molten salt for energy storage.

The new venture, called called SolarReserve, will operate the utility-scale solar thermal projects using technology and equipment developed and manufactured by Hamilton Sundstrand's Rocketdyne unit.

"The molten salt holds its heat very efficiently and for long periods of time," Dan Coulom, spokesman at Hamilton Sundstrand, told Cleantech.com.

Coulum said the company, a subsidiary of United Technologies (NYSE: UTX), plans to build as many as 10 plants over the next 10 to 15 years, pulling in revenues of $1 billion over that time period.

With concentrated solar, a large number of motor-controlled mirrors track the sun and reflect the solar energy onto a tower receiver, which in turn heats a liquid that can be used to make steam. A steam turbine can then produce electricity.

"The molten salt, which is in a storage tank at the bottom of the tower, is run up through the receiver and heated to about 1,000 degrees Fahrenheit," said Coulom.

The company said using molten salt, a mixture of sodium and potassium nitrate, instead of water or oil, allows the heat to be stored for use on cloudy days or at night.

Hamilton Sundstrand, which is a major subcontractor on the International Space Station's photovoltaic solar system, got involved in the more down-to-earth concentrated solar when its parent company grabbed Rocketdyne in 2005 from Boeing (NYSE: BA).

Rocketdyne had been involved for more than 20 years in the U.S. Department of Energy's Solar Two project in Barstow, Calif., which uses Rocketdyne's power tower and molten salt technology.

Take a look at the Solar Two project here >>

That project started in the early 1980s as Solar One using water in a direct to steam system. In 1995, the system was expanded and converted to use molten salt.

Covering about 1,200 acres, the now-decommissioned Solar Two system produced 10 megawatts of power.

The site is currently used by the University of California, Davis, to measure gamma rays hitting the atmosphere.

A planned 15 MW plant based on the Solar Two project is being built in Andalusia, Spain, called Solar Tres. It's backed by a coalition of companies including Sener, Ghersa, Siemens (NYSE: SI) and Saint Gobain, as well as 5 million euros in funding from the European Commission.

Some other solar thermal projects have been getting a lot of attention lately as potentially inexpensive and viable options for utility-scale renewable energy.

In September, Palo Alto, Calif.-based Ausra grabbed $40 million from Khosla Ventures and Kleiner, Perkins, Caufield & Byers, then quickly made deals later that month to build 1,500 MW of solar thermal over the next five to seven years in the U.S. (see Ausra, FPL, PG&E heat up solar thermal).

The total cost of Ausra's deals with San Francisco utility PG&E (NYSE: PCG) and Juno Beach, Fla., utility FPL Group (NYSE: FPL) could reach $4.5 billion.

Ausra's system uses flat plate mirrors called Fresnel reflectors to concentrate the sun's rays directly on water pipes, boiling the water to run steam turbines.

Israel's Solel Solar Systems plans to use parabolic trough technology in its Mojave Solar Park project in California (see Solel's new 553 MW solar thermal plant).

Solel expects to break ground on the 553 MW plant in mid 2009, with the project set to go online in 2011.

The molten salt system from Hamilton Sundstrand and US Renewables could be up and running within three to four years.

"We are talking to prospective customers," said Coulom. "We have confidence that we can sign a deal as early as this year."

Coulum, who said the company is looking at national and international projects, said the size of the systems will depend on the customers.

"It could run at 50 MW, 24 hours a day, or some customers may want it for peak power only, in which case it may run two, three hours a day at 500 MW."