Photovoltaic Device Operation at Low Temperature

The fundamental efficiency of a photovoltaic device is ultimately constrained by the temperature difference between the sun and the PV device. An ideal "Shockley-Queisser" single junction solar cell shows both a rise in limiting efficiency and reduction in optimum band-gap energy as the cell temperature is reduced. In the case of a solar cell that is dominated by parasitic non-radiative recombination at room temperature, an improvement in efficiency is shown when, at low temperature, radiative recombination dominates over all non-radiative modes. This "low temperature, radiatively limited" regime is not suitable for photovoltaic power generation, but is proposed as a useful regime for demonstrating demanding 3^rd Generation photovoltaic device concepts that are otherwise too ambitious to function efficiently at room temperature