Initial Performance Measurements from a Low Concentration Version of an Integrated Compound Parabolic Concentrator (ICPC)

Recent design work has led to the evolution of a simple low concentration version of the ICPC which provides an elegant solution to several potentially expensive or difficult to implement features of previous versions. The idealized optical design of this configuration corresponds to the unit concentration limit for a fin CPC solution which is then coupled to a practical thin wedge-shapedabsorber. Prototype collector modules using tubes with tow different fin orientations have been fabricated and tested in collaboration with Sandia National Laboratories and the National Renewable Energy Laboratory. This paper presents preliminary results from the initial performance measurements on these modules. We find that the instantaneous thermal efficiency at a typical operatingtemperature for cooling (about 130K above ambient) is close to 60% of total insolation. Angular response measurements demonstrate that the full sky coverage and high temperature performance are well matched to the operating requirements for high efficiency (double-effect) solar cooling with a fully stationary collector.