Optical Performances of Refractive Crossed Compound Parabolic Concentrator CCPC

摘要

The design of solar concentrators depends on its application (thermal or PV) and on the tracking system that will be used. Low geometrical concentration ratios (C_g) are ＜10x and generally tend to be static concentrators; in this case they have to be nonimaging concentrators. Nonimaging concentrators allow the collection of sunrays for a certain period of time during the day depending on their acceptance angle. Static concentrators are used in order to avoid using tracking systems especially for use in Building Integrated Photovoltaic (BIPV) applications. This research work discusses the optical performances of the refractive Crossed Compound Parabolic Concentrator (CCPC) for photovoltaic application and compares it with reflective CCPC performances. The CCPC was manufactured and the electrical and optical performance analysed using indoor characterisation instruments. A maximum power concentration of 2.5× was achieved compared to a similar type of non-concentrating module. The developed CCPC system, being static and truncated, achieved a 65° acceptance angle with a high optical efficiency of 75%. The refractive CCPC proved a better performance than the reflective CCPC built from a hollow 3-D geometry with reflective surfaces. In addition to the optical performances, the refractive CCPC is built from cheaper material and uses a cheaper manufacturing process.