Experimental thermal and environmental impact performance evaluations of hydrogen-enriched fuels for power generation

• A dual-fuel carburettor is used for fuel blend preparation. • Up to 20% (volume basis) of hydrogen is mixed with traditional fuels. • CO 2 emissions are reduced by 22–31% at a 20% hydrogen blend. • Hydrogen can offset the power output reductions with fuels other than gasoline. The transition to a low-carbon energy future requires a multi-faceted approach, including the enhancement of existing power generation technologies. This study provides a comprehensive experimental evaluation of hydrogen enrichment as a strategy to improve the performance and reduce the emissions of a power generator. A 3.65 kW power generation that is equipped with spark-ignition engine is systematically tested with five distinct base fuels: gasoline, propane, methane, ethanol, and methanol. Each fuel is volumetrically blended with pure hydrogen in ratios of 5 %, 10 %, 15 %, and 20 % using a custom-developed dual-fuel carburetor. The key parameters, including exhaust emissions (CO 2 , CO, HC, NO x ), cylinder exit temperature, electrical power output, and thermodynamic efficiencies (energy and exergy), are meticulously measured and analyzed. The results reveal that hydrogen enrichment is a powerful tool for decarbonization, consistently reducing carbon-based emissions across all fuels. At a 20 % hydrogen blend, CO 2 emissions are reduced by 22–31 %, CO emissions by 39–60 %, and HC emissions by 21–60 %. This environmental benefit, however, is accompanied by a critical trade-off: a severe increase in NO x emissions, which rose by 200–420 % due to significantly elevated combustion temperatures. Performance is notably enhanced; power output increased by 2–16 %, with hydrogen addition enabling lower-energy–density fuels like methane and propane to achieve performance parity with gasoline. Thermodynamic analysis confirms these gains, with energy efficiency showing marked improvement, particularly for methane, which increased from 42.0 % to 49.9 %. While hydrogen enrichment presents a viable pathway for enhancing engine performance and reducing the carbon emissions of power generators, the profound increase in NO x necessitates the integration of advanced control and after-treatment systems for its practical and environmentally responsible deployment.