Analysis of Irreversible Thermodynamic Losses in Emissive-Energy Harvesters Based on Photon Beams

An analysis of irreversible energy losses that happen upon emissive-energy conversion is presented in this article. For this, we show that in these converters, the total amount of entropy produced in the conversion is proportional to the number of emitted photons, which justifies their description as counterparts of thermophotovoltaic engines. In the last part of this article, using a model of low-intensity photon beams and the detailed balance principle, we show the effects of irreversibilities on the output power and efficiency of emissive-energy harvesters.