Determination of the cooling requirements for single cell photovoltaic receivers under variable atmospheric parameters

The performance of multijunction solar cells in the field varies significantly compared to the rating under standard test conditions; this is mainly due to the spectral sensitivity of such solar cells. The additional losses in the electrical power contribute to the thermal load which needs to be dissipated by a cooling mechanism attached to the back of the receiver. It is important therefore to quantify the heat power under realistic conditions. This paper investigates the cooling requirements of single cell photovoltaic receivers taking into consideration the influence of turbidity (or aerosol optical depth) and precipitable water. It is shown that a heat transfer coefficient greater than 1300 W/m2K is required to keep the solar cell under 100°C at all times.