Active cooling of high concentrator panels with multi-junction modules by confined liquid impingement over the extended surfaces

Abstract

The use of an efficient and reliable method to cool multi-junction cells in a high concentrator photovoltaic/thermal system leads to higher net output power in addition to improving the service life of the cells. The present study numerically investigates the cooling effect of a liquid-confined submerged jet impinged over the extended heat transfer surfaces in the back of the solar cells. The method is considered for the four high concentrator photovoltaic/thermal system designs. All systems include panels with two symmetry lines and four symmetric multi-junction modules under a concentration ratio of 1000 suns and a laminar flow of coolant. Extended heat transfer surfaces were designed as arrangements of rectangular fins inside a heat sink. According to the results, the hybrid cooling designs exhibited better cooling performance than confined jet impingement cooling. The temperature of the solar cells in one of the proposed designs at an inlet mass flow rate of 200g/min was 58.7 °C, which was smaller than the corresponding temperature of 70.4 °C in a similar finless design. For the proposed design, the electrical efficiency of the cells improved from 38.16 % to 38.71 % at the same inlet mass flow rate. This cooling scheme also reduced the temperature non-uniformity across the cells to 3 °C in some of the proposed designs.