Power-to-hydrogen: A review of applications, market development, and policy landscape
Rim BOUKHCHINA, Mohamed Hamdi, Souheïl El Alimi
Abstract
As a result of the shift to low-carbon sustainable energy systems, hydrogen is now a major energy carrier. With an emphasis on hydrogen generation, storage, applications, infrastructure development and policy landscape, this review examines the 'power-to-hydrogen' pathway. While hydrogen constitutes 75% of the universe's mass, scalable terrestrial production remains challenging, with electrolysis efficiencies currently at 60–80% and costs at ＄3–8/kg for green hydrogen. Key applications span steelmaking (reducing 7% of global CO2 emissions) and fuel cells (reaching 60% energy efficiency). Storage solutions, including 700-bar compressed tanks and metal hydrides, face density and safety hurdles. Infrastructure demands ＄15 trillion in investment by 2050 for pipelines and refueling stations. Policy levers like carbon pricing (<＄100/ton CO2) and research and development (R & D) subsidies are critical to accelerate deployment. The carbon price, subsidies, and further research will all influence the direction of hydrogen in the future. Notwithstanding the obstacles, policy, technological, and infrastructure advancements can fully realize hydrogen's potential to revolutionize the world's energy system. From both global and universal perspectives, this review seeks to raise public understanding of hydrogen's critical role in a sustainable energy future.