On thermodynamic inconsistencies in several photosynthetic and solar cell models and how to fix them

TL;DR

This paper identifies thermodynamic inconsistencies in common models of solar cells and photosynthesis, proposing a Hamiltonian-based transfer method that aligns with the second law of thermodynamics.

Contribution

It introduces a thermodynamically consistent modeling approach replacing decay rate assumptions with explicit Hamiltonian transfer.

Findings

Decay rate models violate the second law of thermodynamics.

Hamiltonian transfer predicts different energy transfer efficiencies.

Models with decay rates may lead to incorrect conclusions.

Abstract

We analyze standard theoretical models of solar energy conversion developed to study solar cells and photosynthetic systems. We show that the assumption that the energy transfer to the reaction center/electric circuit is through a decay rate or "sink", is in contradiction with the second law of thermodynamics. We put forward a thermodynamically consistent alternative by explicitly considering parts of the reaction center/electric circuit and by employing a Hamiltonian transfer. The predicted energy transfer by the new scheme differs from the one found using a decay rate, casting doubts on the validity of the conclusions obtained by models which include the latter.