PERFORMANCE EVALUATION OF ASYMMETRIC CPC-PVT COLLECTORS CONNECTED IN SERIES

In this study, a series of thermal-photovoltaic collectors with hybrid reflector geometry and flat plate receiver is investigated experimentally and analytically through fundamental equations regarding solar collectors. The series of five compound parabolic thermophotovoltaic collectors are located in Athens, Greece and the experiments took place in June at open circuit state, i.e. the collectors were not electrically connected. The developed model combines optical and thermal analysis. The main objective of this study is to determine the thermal and the exergetic performance of the collectors under various operating conditions. For these reasons, the developed model is validated with the respective experimental data and afterwards, the solar collector model is examined parametrically for different tilt angles. The experiments are performed with water as heat transfer fluid and for low temperature levels up to 60 degrees C. The final results proved that the investigated solar collectors are able to produce about 2.8 kW useful heat for low working fluid mass flow rates exhibiting at the same time an exergetic efficiency of nearly 1.4%. Also, the results of the developed model showed that the maximization of the produced thermal energy during summer occurs at a tilt angle of 10 degrees.