Talk about landing the Holy Grail of solar power. Santa Monica startup SolarReserve locked in $737 million in guaranteed loans from the U.S. Department of Energy recently for its highly innovative solar energy plant.
Unlike other concentrating solar power (CSP) plants, the new Crescent Dunes Solar Energy Project in Nevada has multiple game-changing features. One, it can produce power 24/7, even after the sun goes down, a feat considered impossible til now.
And two, it uses incredibly hot molten salts to generate renewable electricity. Water is traditionally used in solar towers such as this one, but SolarReserve discovered that when it comes to CSP, salt trumps water in pretty much every way possible.
How? For starters, salt is an abundant natural resource and thus cheaper to produce. In addition, it can be heated to higher temperatures and stays heated overnight, creating electricity with or without the sun. It’s also the most efficient material to store solar energy, and is both nonflammable and nontoxic.
The plant works by aligning giant mirrors, called heliostats, in a circle to reflect sunlight to a central tower, filled to the brim with millions of gallons of molten salt. The salt heats up to 1,050 degrees Fahrenheit, generating enough steam to drive a turbine and produce electricity. Thanks to salt’s natural properties, it then stays hot for 10-12 extra hours per day, allowing for significantly more power production at a cheaper cost.
The DOE’s loan guarantee sends a message of clear support to the solar thermal industry. Loans such as these are typically awarded to plants developing and employing photovoltaic arrays, much like those widely used to generate home solar power. Solar thermal can certainly use all the help it can get.
If you’re wondering how a plan so brilliant came to be, the project was spearheaded by actual rocket scientists from RocketDyne, a division of United Technologies. Though the salt tower plant remains untested on a large commercial scale, scientists were able to convince the federal government that it will indeed pay off.
In fact, the end result will be an impressive 100 MW and 480,000 MWh of clean, renewable energy from the sun, or enough to power 75,000 homes during peak output. Not only that, but the project will create 400-500 temporary construction jobs and 50 permanent jobs to economically boost Nevada, a state hard hit by the recession.
Solar entrepreneurs everywhere should study this model closely, as it’s sure to pick up steam in the coming months.
Brittany Mauriss is an editor and resident solar expert at GreenMarketing.TV, the green entrepreneur’s source for start-up ideas and insightful interviews with the industry’s top thinkers. She also blogs over at EntrepreneursforaChange.com.