Coupling high-temperature electrolysis and industrial waste heat for on-site green hydrogen production: energy, economic and environmental analysis

High-temperature electrolysis offers a solution for industry decarbonisation by high-efficiency hydrogen production. This study presents a system based on Solid Oxide Electrolysis Cells (SOEC) fed by photovoltaic and waste heat recovery, for hydrogen blending with natural gas in industrial burners. The aim of this work is to assess techno-economic feasibility of the proposed configuration, investigating hydrogen blending limits, Levelized Cost of Hydrogen (LCOH), and decarbonisation cost. LCOH values below 6 €/kgH2 cannot be achieved at current SOEC costs. The system can be applied without significant burner modifications, since maximum hydrogen volumetric fractions are less than 20 %. Higher efficiency and emission reduction potential in comparison to alkaline electrolysers can be achieved, but they are offset by higher LCOH and carbon abatement costs. Forthcoming reduction in SOEC costs can improve the cost-effectiveness and high natural gas prices experienced during the energy crisis make the decarbonisation cost competitive with the emission trading system.