Comparative analysis of solar-driven PEM water electrolysis systems for hydrogen production

With the increasing demand for promoting the utilisation of renewable and clean energy resources, solar-driven proton exchange membrane (PEM) water electrolysis systems have gained significant attention as an effective energy conversion technology for green hydrogen production. This study aims to address the performance difference among different configurations of solar-driven PEM water electrolysis systems, so as to provide guidance for system design and optimisation. By coupling TRNSYS with MATLAB, we have established a model for annual performance simulation, based on which comparative analysis of photovoltaic-PEM (PV-PEM), PV/thermal-PEM (PV/T-PEM), and PV-solar thermal-PEM (PV-ST-PEM) systems has been performed, using meteorological data from Nicosia, the capital of the Republic of Cyprus. The results demonstrate that the PV/T-PEM system achieves the highest average solar-to-hydrogen efficiency of 3.5% and PEM energy efficiency of 80.0 % on a typical day in summer. The PV/T-PEM system also exhibit annual hydrogen production of 57.1 L/m². By employing PV/T collectors, electricity and thermal energy can be simultaneously generated without compromising the solar array area dedicated to electricity generation compared to the PV-ST configuration. It can be concluded that PV/T-PEM systems hold significant potential as a viable solution for enhancing energy efficiency for hydrogen generation.