Solar Energy Collection Using an Absorber with a Thermal Compensator

A fairly steady power output solar-thermal energy collector to produce steam has been fabricated and tested. The basis of this study was the fact that most solar collectors do not give steady energy output due to fluctuations in solar intensity. A Parabolic Dish Solar Collector (PDSC) was constructed and an absorber was positioned at the focus. Water was made to flow through a narrow pipe in and out of the absorber so as to absorb heat energy. The absorber had a temporary thermal storage component consisting of a Phase Change material (PCM) which would gain latent heat of fusion at the melting temperature and then release the same quantity of heat during solidification. This heat storage-recovery mechanism acted as a thermal compensator in the absence of intense radiation. The maximum efficiency of the system with thermal compensator was found to be 44.82% while that of non-compensated system was 11.60%. The thermal compensation effect was tested by simulating a cloudy condition by temporarily obstructing the solar beam and then measuring the energy output. The Solar Energy Device (SED) was found to give stable and reliable power output during the solar harvesting period.