The plant uses a concentrated solar thermal design with more than 300,000 software-controlled mirrors that track the sun and reflect sunlight onto boilers at the top of three towers. The concentrated sunlight hits the boilers’ pipes and heats the water to create steam that drives turbines to produce electricity for as many 140,000 California homes during peak operation.
San Bernardino County fire captain Mike McClintock told the Associated Press that the fires were caused by misaligned mirrors that focused sunbeams on a lower section of one of the towers, causing electrical cables to catch fire. The burnt tower is now shut down for investigation and repairs and the plant is operating at only a third of its capacity, since another tower is also shut down for maintenance. It is presently unclear if the fire will affect California’s electric supply.