Entropy production in a p-n photovoltaic converter

TL;DR

This paper applies irreversible thermodynamics to analyze entropy production in a non-biased p-n photovoltaic cell, integrating electronic and electrical processes to derive a comprehensive voltage equation and explore the effects of cell parameters.

Contribution

It is the first study to simultaneously consider electronic and electrical processes in a PV cell within thermodynamics, deriving a new voltage equation including recombination resistance and collection factors.

Findings

Derived a new voltage equation incorporating recombination resistance and collection factors.

Provided thermodynamic insights into the empirical parallel resistance in biased PV cells.

Analyzed entropy production in PV cells considering both electronic and electrical processes.

Abstract

The case of a non-biased (light excited) p-n photo-voltaic (PV) cell working in a closed circuit with a resistive load is investigated by means of irreversible thermodynamics in the linear range. To our knowledge, this is the first time that both electronic processes, such as photo-excitations, carrier diffusions and recombinations, and electrical processes, such as current generation and the Joule effect, are considered together in the context of thermodynamics. An equation for the built-up voltage is obtained where the recombination resistance of the diode and a collection factor of the photo-carriers, depending on the thickness of the illuminated cell-side, are included in a natural way.depending on the thickness of the illuminated cell-side, are included in a natural way. The case of a biased PV-cell is also considered concerning the empirical parallel resistance introduced in realistic models. Some insights into its real meaning have been obtained.