Hydrogen energy system with renewables for isolated households: The optimal system design, numerical analysis and experimental evaluation

• We model the self-sufficient energy system with renewables and hydrogen storage.
• Required large renewable production capacities result in low capacity factors.
• The electrolyser operates mostly with its nominal power, while fuel cell's varies.
• Hydrogen energy seasonal storage enables 100% renewable power supply.
• Experiment validates model design and alternative use of hydrogen technologies.

One potential solution for stand-alone power generation is to use hybrid energy systems with hydrogen storage. In this paper, the physical behaviour of a hydrogen energy system with renewables has been numerically simulated and experimentally re-enacted. A reference household in Slovenia's coastal region was used to identify the optimal energy system design, by considering the geographical location, availability of energy sources, actual load dynamics, and components’ technical and economical characteristics. The results show that optimal electricity supply is technically feasible with a 100% renewable system, consisting of wind turbines and solar photovoltaic arrays, including hydrogen technologies (electrolyser, hydrogen tank, fuel cell). The optimal feasible system capacity (33 kW), with the lowest total net present cost (€136,063), is approximately eight times larger than the peak power demand (3.8 kW). The experimental work was performed at hydrogen laboratory facilities. Experiments proved the possibility of alternative uses of existing industrial hydrogen technology for balancing power supply and demand, with a mere 3% deviation from numerical results