Limiting photovoltaic monochromatic light conversion efficiency

Notwithstanding the relatively low energy conversion efficiencies typical of standard solar photovoltaic systems, photovoltaic cells are shown, in principle, to be capable of converting well-collimated monochromatic light at efficiencies arbitrarily close to 100%. To approach such efficiencies, radiative recombination must be the main recombination process within the cell. The intensity of the monochromatic light must be high, and the cell should be designed so that it does not absorb or emit light outside the range of angles and wavelengths required to accept the incident monochromatic light. The thermodynamic basis of such high efficiency is also briefly discussed. Copyright (C) 2001 John Wiley & Sons, Ltd.