Hydrogen-Enhanced Combustion of Hydrocarbons

Strong policy momentum is supporting the adoption of hydrogen as a major energy carrier for a decarbonised global economy, especially for reducing emissions in hard-to-abate industrial sectors. Although achieving large-scale hydrogen deployment will require substantial long-term investment in dedicated infrastructure, blending hydrogen with conventional hydrocarbon fuels provides a practical near-term pathway to accelerate uptake by leveraging existing systems and fuel-supply networks. To inform future research and development in this field, this review summarises experimental and numerical findings on the combustion behaviour of hydrogen–hydrocarbon mixtures and highlights the main challenges and research gaps that must be addressed to ensure the safe and efficient use of hydrogen-enriched fuels in current combustion systems. It also examines the fundamental combustion characteristics of hydrogen and hydrogen-enriched fuels, the effects of hydrogen addition to gaseous, liquid, and solid fuels on combustion performance and emissions, and the contrasting policy approaches shaping hydrogen uptake across major global economies.