The Ivanpah concentrated solar array plant, just north of Mojave National Preserve in southern California. According to Wikipedia: “It uses 173,500 heliostats, each with two mirrors focusing solar energy on boilers located on three 459 feet (140 m) tall[9] solar power towers.” 3500 acres of desert habitat were utterly wiped out for this project, which turned out to be an ineffective boondoggle.