High-temperature green hydrogen production. A innovative– application of SOEC coupled with AEC through sCO2 HP

This study evaluates a potential coupling between AEC and SOEC through a CO2 heat pump unit that works in super-critical conditions. In such a way, thermal power requested by SOEC can be provided by recovering heat loss from AEC via the CO2heat pump. The coupled configuration is characterized by renewable electric input. Hence, the power is provided for electrolysis without more external thermal resources. The energy, economic and environmental impacts of such intervention have been determined and compared with SOEC in solo mode. The layout is created and simulated in a MATLAB SIMULINK environment. The simulation results show a potential improvement in the total energy efficiency of the whole system without an external heat resource, up to 68%, which is higher than 65% of SOEC itself, thanks to the heat recovery section that is correlated with sCO2 HP contribution. LCOH varies widely depending on SOEC size from around 2.59 €/kgH2 up to 9.27€/kgH2.