Abstract

Photovoltaic (PV) grid-connected system is nowadays a well established industry. For PV inverters, European (EURO) efficiency and California Energy Commission (CEC) efficiency have been defined, as Figures of Merit (FoM) allowing easy PV inverter efficiency estimation, while including consideration on PV variability. This paper explores the applicability of weighted efficiencies for off-grid H-2 production system with DC-DC connection of the PV source, for both DC-DC converter, and electrolyzer. The study considers precise modeling of the system, and evaluation of its operation and efficiency over real scenario, with environmental data of three locations considered, with minute-based resolution, allowing precise simulation. Evaluation of EURO and CEC efficiencies for DC-DC converter and electrolyzer demonstrate the accuracy of the FoM with error lower than 1.23% and 3.70% respectively. It is finally recommended the use of weighted efficiencies for the evaluation of off-grid H-2 production systems, allowing fast and accurate comparison between different electrolyzer and DC-DC converter technologies while designing new plants.