Experimental Study of a Parabolic Trough Medium Temperature Solar Thermal System

A parabolic trough concentrator (PTC) with a rim angle of 84˚, a length of 4.2 m, and anaperture area of 6.72 m2 was designed and manufactured in a way required relatively simple technology and skill. An experimental system with the PTC as the core part was assembled on the top of the Teaching Building No.7 of Ludong University (in Yantai, China). A PLC solar tracking system is employed to realize an orientation of a north-to-south direction. According to the international and national standard, thermal performance of the PTC was measured under various weather and working conditions. The experimental results reveals that the effective radiation, which considers the optical influences including the shading effect, cosine effect, incident angle modifier and end loss, deserves great attention. Peakefficiencyof72% was obtained from the experiment.