Design of CPC Photovoltaic Solar Collectors

摘要

Two new photovoltaic solar collectors have been designed, built and tested. A substantial improvement in performance has been achieved in that they produce more electrical power and use significantly less photovoltaic material per unit area than the present state-of-the-art flat panel arrays. A reflective style Compound Parabolic Concentrator (CPC) optical system was used for one collector, and a dielectric style (DCPC) optical system was used for the other collector to concentrate sunlight onto custom designed photovoltaic solar cells. For these two panels only periodic angular adjustments are required, which eliminates the need for two-axis tracking. A modular design of individual sub-units containing an array of series and parallel circuits allows a user to select a variety of operating conditions. The dielectric CPC panel can provide a peak voltage selected from the range of 6V to 120V dc, in steps of 6V, and a peak current from the range of 23A to 1.15A, in 1.15A increments, respectively. The modular design also allows rapid replacement and repair of individual sub-units. The mechanical assembly was designed to withstand a very heavy load of 250 Kg/m exp 2 . The reflective CPC photovoltaic panel is 1.22m by 1.22m, requires thirty-six adjustments per year, and delivers 97 peak watts under 1 kW/m exp 2 of direct insolation. The dielectric CPC panel is also 1.22m by 1.22m, but only requires ten adjustments per year, and delivers 138 peak watts under 1 kW/m exp 2 of direct insolation. The net energy conversion efficiency over the entire dielectric CPC panel, including the frame, was 10.3%. The design considerations for these panels are summarized. (ERA citation 03:042430)