Green Hydrogen Production at the Gigawatt Scale in Portugal: A Technical and Economic Evaluation

The European Union has committed to achieving carbon neutrality by 2050 and green hydrogen has been chosen as a priority vector for reaching that goal. Accordingly, Portugal has drafted a National Hydrogen Strategy laying out the various steps for the development of a green hydrogen economy. One element of this strategy is the development of a gigawatt-scale hydrogen production facility powered by dedicated renewable electricity sources. This work presents an analysis of the technical and economic feasibility of a facility consisting of a gigawatt-scale polymer electrolyte membrane electrolyser powered by solar photovoltaic and wind electricity, using the energy analysis model EnergyPLAN. Different capacities and modes of operation of the electrolyser are considered, including the complementary use of grid electricity as well as different combinations of renewable power, resulting in a total of 72 different configurations. An economic analysis is conducted addressing the related annualised capital expenditures, maintenance, and variable costs, to allow for the determination of the levelised cost of hydrogen for the different configurations. This analysis shows the conditions required for maximising annual hydrogen production at the lowest levelised cost of hydrogen. The best options consist of an electrolyser powered by a combination of solar photovoltaic and wind, with limited exchanges with the electricity grid, and a levelised cost of hydrogen in the range 3.13–3.48 EUR/kg.