Predicted annual energy yield of III-V/c-Si tandem solar cells: modelling the effect of changing spectrum on current-matching.

High efficiencies of >30% are predicted for series-connected tandem solar cells when current-matching is achieved between the wide-bandgap top cell and silicon bottom cell. Sub-cells are typically optimized for current-matching based on the standard AM1.5G spectrum, but in practice, the incident radiation on a solar cell can be very different from this standard due to the effects of the sun's location in the sky, atmospheric conditions, total diffuse element etc.