Solar reflectors at Albuquerque, power station
Rows of solar reflectors at an experimental solarpower station located near Albuquerque, NewMexico. This facility consists of an array ofheliostats, large mirrors mounted on moveableframes, which track the sun across the sky andconcentrate its light onto a heat exchangermounted on top of a tower at the centre of thesite. A pressurized fluid inside the heatexchanger carries the heat to a steam generator.The steam created drives turbines to produceelectricity.
© John Mead/Science Photo Library
A photovoltaic system of solar cells
Camp Pendleton is going greener with the use of renewable energy, by developing a photovoltaic system of solar panels. The photovoltaic system uses solar cells to convert light into electricity, generating 1.48 megawatts of renewable energy annually, and will also power 5 percent of the base's daily energy use. The system has 225 panels, with each panel featuring 28-235 watt-modules tallying 6, 300 photovoltaic components for all six acres.
© Stocktrek Images
Birth of solar steam power
Illustration of a solar powered motor installed at Cawston Ostrich Farm, South Pasadena, California in 1901. It consisted of a conical dish lined with 1700 mirrors which concentrated sunlight on to a steel tube placed in the centre of the dish, thus heating the 100 gallons of water it contained. The steam produced drove an engine connected to an electrical power generator and was capable of pumping about 1400 hundred gallons of water a minute. The dish, driven by clockwork, followed the movement of the sun. Cawston Ostrich Farm was the first enterprise in the United States to use a solar powered motor for commercial purposes. It was used to irrigate the arid soil of Southern California. This is the forerunner of Concentrated Solar Power systems (CSP) using self-moving mirrors (heliostats) to follow the sun and which concentrate sunlight onto a steam producing boiler.
© SHEILA TERRY/SCIENCE PHOTO LIBRARY