So I find this extremely cool. Meet the U.S. Government's entry into solar-thermal. So here's the deal, Solar Two (an extension of its predecessor Solar One), had a collection of 2,493 mirror arrays, or heliostats, that all focus the sun's energy at the central tower. This tower is full of salts that become molten under the glare of all the mirrors. That heat is then used down the line to boil water, turning turbines and generating up to 10 MW of power. Although Solar Two was a success, it was sadly decommissioned in 1999. On the bright side, the technology has gone commercial, and Solar Tres is currently being built in Spain using the technology proven with One and Two. More at: www.solarpaces.org/SOLARTRES.HTM