Design, manufacturing and performance of an concentrating solar collector

Concentrating solar collectors have the advantage of operating at much higher temperature than conventional flat plate collectors. In this study, an absorbing fluid parabolic trough concentrating solar collector was designed, built and tested for an optimum geometric size and shape following an analysis of the design. The working fluid, a dye (black fluid) was made to flow through a glass tube to take advantage of the direct absorption process and the increase in the effective transmittance-absorptance product. The compound parabolic concentrator (CPC) has the advantage of collecting diffuse radiation more efficiently and has the advantage of being simpler and cheaper. The reduced cost per unit energy collected and ease of manufacture are also noted since few metal parts are required in the collector fabrication, except for the aluminum reflector. Performance testing shows relatively high collector efficiency compared to some of the published data. An optimum mass flow rate and dye concentration was also obtained.