A three Dimensional Compound Parabolic Concentrator (3-D CPC) has been developed to collect solar energy and to achieve the highest possible concentration. The significant research work describes the methodology to bring out the performance of 3-D CPC reflector profile that is designed and fabricated for a half acceptance angle of 4º in support of a spherical absorber with radius 100 mm. In the present work, two types of absorber coating materials are used in 3-D CPC modules, one with a commercially available ordinary Black paint (3-D CPC IA) and another with a BlackNickel-Tin (3-D CPC IB). The optical efficiencies of 3-D CPCs have been projected hypothetically and comparisons have made among the experimental values. The study examines the values of optical efficiencies that are experimentally determined are in good agreement with the values that are predicted theoretically. Optical performance of 3-D CPC IB has been enhanced by selective coating to the absorber.

Keywords : 3-D CPC; Optical Efficiency; Black Nickel– Tin; Solar Energy.