Distributed solar collector

 

It is distributed system of individual solar collector modules interconnected to a single power producing unit by the means of a heat transfer medium. This is also known as Parabolic Trough Systems.

In distributed receiver power plants, parabolic trough collectors with line focus are most commonly used. The sun rays are reflected by parabolic or cylindrical troughs. The reflected rays are focused on linear conduit (pipe) located along the axis of the trough.

Parabolic Trough Systems use a linear parabolic concentrator with a mirrored surface to focus solar radiation on an absorber pipe running along the focal line of the parabola. The absorber pipe contains the Heat Transfer Fluid or HTF which is heated and pumped to the steam generator. The steam generator is in-turn connected to a steam turbine. For change of the daily position of the sun perpendicular to the receiver, the trough tilts east to west so that the direct radiation remains focused on the receiver. However, seasonal changes in the in angle of sunlight parallel to the trough does not require adjustment of the mirrors, since the

Figure 2.12 - Solar thermal Electric power plant using distributed solar collectors

light is simply concentrated elsewhere on the receiver. The receiver can reach temperatures of 400 °C and generates live steam to drive the steam turbine, which coupled with generator.