Temperature uniformity enhancement of densely packed high concentrator photovoltaic module using four quadrants microchannel heat sink

Abstract

The dense solar radiation received by a high concentration photovoltaic module (HCPVM) causes a high cell temperature. In this module, multiple solar cells were electrically connected in both series and parallel. The higher temperature of the solar cell in the series string limits the generated power for the whole string. Therefore, it is crucial to employ a uniform cooling mechanism for higher electrical performance along with a longer lifespan. The uniform cooling is required to attain safe operating temperature and prevent the hot spot formation. Hence, in the current work, a four-compartment microchannel heat sink is proposed for the thermal management of HCPVM under high solar concentration of 1000 suns (1 sun = 1000 W/m2). A three-dimensional (3D) conjugate heat transfer model with exergy analysis is developed and validated. This model was used to investigate the effect of inlet and outlet orientation of four quadrants microchannel heat sink as a cooling method for HCPVM. Eight different orientations of parallel-flow and counter-flow conditions were investigated and compared in terms of temperature non-uniformity, module power, and exergy performance. The results showed that the inlet and outlet orientation was a key role affecting the module temperature non-uniformity. For the counter-flow operated heat sinks, the HCPVM can be operated under a temperature non-uniformity of 3.1 °C at total inlet module mass flowrate of 350 g/min and solar concentration ratio of 1000 suns. In addition, the attained HCPVM electrical, thermal, and overall exergy efficiency were 37.2%, 8.2%, and 45.4% respectively at the same conditions.