The effect of temperature on the efficiency of concentrator PV modules with MJ SC

Presented is a method for calculating the power-productivity of photovoltaic (PV) installations with sunlight concentrators and multijunction (MJ) solar cells (SC) allowing for variation of their power efficiency in dependence on real operation conditions - spectral composition and sunlight flux density and also on temperature of multijunction cells. The yearly totals of specific electric power generated by a module at constant and variable efficiency values have been calculated. It has been shown that allowing for the joint effect of the sunlight characteristics and multijunction SC temperature on the photovoltaic module efficiency must be realized in simulating the module operation in any power generating systems. These allows excluding the overestimations of the yearly power totals generated by a solar installation in determining the power productivity.