Enhancing the performance of low-concentrator photovoltaic systems using novel configurations of radially microchannel heat sinks

An innovative cooling method for concentrator photovoltaic (CPV) systems is essential to control the temperature of photovoltaic cells to boost the net output power and extend their lifetime. Thus, novel designs of radially flow microchannel heat sinks are developed. Three different configurations of single-layer radial microchannel (Conf. A), double-layer radial microchannel (Conf. B), and double-header radial microchannel (Conf. C) are studied. The new designs offer a symmetrical distribution of coolant through the heat sink with lower pressure drop. Consequently, a higher temperature uniformity over the cell surface is attained along with lower thermal stresses. A comprehensive three-dimensional thermal model for the concentrator photovoltaic system coupled with the proposed heat sinks was developed and numerically simulated. The results revealed that the new heat sink configurations significantly decreased the silicon layer temperature while maintaining high-temperature uniformity. Furthermore, when compared to other configurations, using the double-header heat sink (Conf. C) achieved the lowest cell temperature (83.6 °C) at the highest temperature uniformity with the deviation of 1.8 °C, the minimumpumping power of 1.4 W and the highest net electrical power of 42.7 W at a solar concentration ratio (CR) of 20 suns. Finally, the CPV system coupled with Conf. C attained the minimum unit price of electricity at 8 Ȼ/KWh compared to 16.9 Ȼ/KWh form the utility in the United States.