Practical Factors Lowering Conversion Efficiency of Hot Carrier Solar Cells

We have evaluated the influence of practical factors on the conversion efficiency of hot carrier solar cells, from which photogenerated carriers are extracted before being completely thermalized. Equilibration and thermalization of the carriers, and energy dissipation associated with hot carrier extraction were involved in a thermodynamic modeling. Among them, thermalization has been found to have the greatest impact. Even though a 1 ns thermalization time could be realized, the conversion efficiency is close to the Shockley-Queisser limit (34%) under 1 sun irradiation, and lower than the limiting values of triple-junction cells (around 60%) at 1000 sun. (C) 2010 The Japan Society of Applied Physics