Tuesday, May 24, 2011
Solar Power at Night
One of the biggest problems with solar energy is that it works, on average, less than 12 hours a day. There are many possible ways to store energy (flywheels, pumping water uphill, etc.) but all involve a lot of waste. A new solar plant just approved for the California desert will fight this problem using salt. It will be set up like the solar thermal tower shown above, but instead of turning water to steam like most such plants it will melt salt and heat it to about 1000 degrees Fahrenheit. The molten salt will stay hot enough all night to keep creating steam and thus generating power. I don't know much about the engineering but the company behind the venture, Solar Reserve, says it will be economically competitive.