A THERMODYNAMIC CYCLE FOR PHOTOVOLTAIC ENERGY-CONVERSION

The possibility of creating a Carnot cycle for photovoltaic energy conversion is explored. The thermodynamic functions for an electron-hole gas are derived and they are used to show that a conventional Carnot cycle involving two heat reservoirs can be constructed. The additional problems which arise from radiative energy transfers are show to lead to the result that only if the electron-hole plasma is simplified to the two-level case can a reversible cycle occur. Since this cycle requires an infinity of reservoirs it is not a Carnot cycle in the sense of classical thermodynamics. © 1990 IOP Publishing Ltd.