Page - 111 - in Water, Energy, and Environment - A Primer

A separate type of linear concentrator system is the Fresnel reflector system, where one receiver tube is positioned above several curved mirrors. This configuration allows the mirrors greater flexibility in tracking theSun. 8.2.2.3 Dishengine The third type of CSTP technology is the dish engine system in which a dish-shaped receiver (usually multi-faceted to reduce manufacturing costs) directs sunlight onto a thermal receiver at the focal point of the dish (see Figure 8.8). The receiver absorbs the heat and transfers it to a heat-driven engine generator (typically a Stirling engine) with a working fluid such as hydrogen gas. Each dish rotates along two axes to track theSun. Figure8.8 DishengineCSTPsystem(Source:U.S.NationalRenewable EnergyLaboratory). Renewableenergy 111