Comparison of the normalized efficiency of solar cells of different structures obtained from our model with the published results of Sanyo 4; 5. The latter are shown in red, while our results are in black. The temperature coefficient of the normalized conversion efficiency for the conventional P/N diffused junction solar cell is –0.45% / °C (Sanyo 4), while it is –0.39% / °C in our case. For HIT cells on N-type wafers, Sanyo results vary from –0.33% / °C 4 to –0.25% / °C 5, while it is –0.32% / °C in our case. For HIT cells on P-type wafers we obtain a temperature coefficient –0.28% / °C.