Concentrating solar thermal projects fell out of favor more than 15 years ago, when the last SEGS plant was commissioned. But advances in reflective mirror, thermal receiver, and tracking system technologies have significantly improved the systems' energy conversion efficiency at a much lower capital cost. POWER recognizes Nevada Solar One as a 2007 Top Plant for pushing the limits of solar thermal technology and for being the first of a new generation of concentrating solar projects now being developed around the world.