Hydrogen - imminent clean and green energy: Hydrogen production technologies life cycle assessment review

The demand for sustainable energy sources and rising concern over climate change have spurred interest in hydrogen as a green energy source. Several industries' decarbonization, including transportation, manufacturing, and power generation, has the potential to be significantly aided by hydrogen. Hydrogen can be produced from renewable and non-renewable resources which are discussed with emphasis on recent developments and hydrogen generation pathways associated with these technologies. Life cycle assessment (LCA) studies of these processes are crucial to have an understanding of the factors affecting hydrogen production in policy decisions and awareness of advanced strategies status to improve the efficiency of hydrogen production. Technologies are analysed using published LCA studies and discussed to examine hydrogen production's environmental impact and evaluate the hydrogen market. The study shows that renewable energy sources and natural gas steam reforming for hydrogen production have a high energy content and lack of CO2 emissions, chosen as a potential alternative fuel. Further discussion on bottlenecks and future perspectives to overcome the challenges in hydrogen production are presented. This review aims to provide details on advances and new emerging knowledge developing and the state of hydrogen implementation as a sustainable alternative to fossil fuels to accelerate the net zero carbon emission goals. © 2024 The Institution of Chemical Engineers