Ideal efficiency of monolithic,series‐connected multijunction solar cells

Two‐terminal, monolithic tandem solar cells represent the most interesting implementation of tThe multijunction photovoltaic array capable of very high efficiency. Radiative coupling among the cells, and between the cells and the substrate, along with series interconnection are features present in this approach. Their effect on efficiency is quantified for arrays with a small number of cells in the radiative limit and compared with the best experimental cells to assess their potential improvement. Finally, it is shown that they do not lower the limiting efficiency of the infinite tandem array, which is determined by the emission losses through the illuminated face. Copyright © 2002 John Wiley & Sons, Ltd.