A device used to capture heat from the sun and turn it into energy. Solar energy captured by collectors is most commonly used for home water or pool heating. The collector may consist of a variety of materials in different forms, such as a coil of copper or plastic tubing, straight lengths of tubing, or flat plastic panels with passages through them. The coils or panels are exposed to the sun’s rays, either in an insulted box under glass, or exposed to the elements. Water is pumped through the tubes or panels, absorbing their heat. The hot water in the tubes or panels may then be stored in an insulated tank for later use. Also called solar panels.