An experimentally validated curve-fit model of a hydrogen-fueled internal combustion engine for use in techno-economic analyses

The growing share of renewables in power grids increases the need for backup generators able to compensate production profiles whenever needed. Hydrogen internal combustion engines (H 2 ICEs) offer a promising solution in terms of flexibility, reduced capital cost, and looser requirements on hydrogen purity. These systems are, however, still not well characterized. This study introduces a zero-dimensional (0D) model for a 100 % hydrogen engine, calibrated using experimental data under varying loads and air-fuel ratios. Unlike existing models, it proposes validated electrical efficiency data across multiple operating points. Efficiency curves are provided in quadratic and linear forms, allowing integration into diverse energy system simulations, including linear programming. The model performance is evaluated in a peak-shaving case study using real data from a remote site with limited grid supply. Three engine-generators are used to match single-minute resolution load demand. Compared to typical models that lack validation and ignore part-load efficiency losses, the proposed model highlights differences in hydrogen consumption estimation up to 13.4 %, thus offering improved accuracy for techno-economic analyses of hydrogen-based systems. • Advanced efficiency modeling for hydrogen engine-generator for techno-economic analyses. • Accurate estimates also in partial load operating conditions for H2 ICEs. • Experimentally validated fuel conversion efficiency curves. • When compared to existing models, significant changes in hydrogen consumption are seen.