TAHESHI TAKAHARA / SCIENCE PHOTO LIBRARY TAHESHI TAKAHARA / SCIENCE PHOTO LIBRARY
The 'Sun Trac' photovoltaic concentrator array. This device is an array of single-crystal photovoltaic cells. The cells are relatively efficient, but are very expensive. The Sun Trac uses fresnel lenses to concentrate the Sun's light onto a series of smaller (thus cheaper) cells. In this way the whole area of the collector may be utilised, without the cost penalty of very large silicon cell sizes. A computer and a 'Sun sensor' are used to ensure that the Sun Trac is pointing directly toward the Sun at all tims during the day. Sun Trac is an experimental device; many such collectors would be used to provide electrical power in remote places.
Model release not required. Property release not required.