Global techno-economic and life cycle greenhouse gas emissions assessment of solar and wind based renewable hydrogen production

This study conducts a global assessment of renewable hydrogen production using solar photovoltaic (PV), wind, and hybrid PV/wind systems, integrated with proton exchange membrane (PEM) electrolyzers. A multi-objective optimization is applied to evaluate techno-economic performance and life cycle greenhouse gas (GHG) emissions, accounting for embodied emissions in the system's components. Results identify optimal configurations to minimize levelized cost of hydrogen (LCOH) and carbon intensity (CI) of hydrogen, showing potential reductions of cost and CI by 2030. Specifically, standalone PV systems can achieve LCOH less than 6.5 USD/kg H2 and CI below 2.5 kg CO2eq/kg H2 in high-irradiance regions such as Middle East and North Africa (MENA) region and Chile. Wind systems in regions like MENA, Australia and Central USA can reach LCOH below 5 USD/kg H2 and CI below 1.5 kg CO2eq/kg H2. Hybrid systems emerge as the most effective configuration, maximizing the renewable energy use and minimizing both LCOH and CI. Moreover, technological advancements and further cost reduction in renewable technologies and PEM electrolyzers, along with O2 co-product utilization, could reduce LCOH of all the RES-based hydrogen systems below 1 USD/kg H2 and achieve negative CI in several key regions