PG&E has decided to scale back the Alpine SunTower farm in California and replace eSolar's field of heliostats with PV panels. (greentechmedia.com)
Price ran the numbers for designs for various heliostat field sizes of 350, 400, 450, and 500 MWt, all integrated into a 250 MW gross power cycle, to run for 5 or 6 hours of reliable capacity from 3 or 4 pm to 9 pm during the summer months, and with a 30 - year project life. (solarpaces.org)
However, instead of using fossil fuels or nuclear power to create the steam, BrightSource uses sunlight, reflected by thousands of small mirrors called heliostats onto a boiler filled with water that sits atop a tower. (brightsourceenergy.com)