Techno-economic analysis with electrolyser degradation modelling in green hydrogen production scenarios

A pivotal ambition to aid global decarbonisation efforts is green electrolytic hydrogen produced with renewable energy. Prolonged operation of water electrolysers induces cell degradation, decreasing production efficiency and gas yield over the lifespan of the electrolyser stack. Considerations for degradation modelling is seen to a varying extent in previous literature. This work shows the effects of including degradation modelling within existing system scenarios and new ones to demonstrate the impact of inclusion on key techno-economic parameters. A fundamental Anion Exchange Membrane electrolyser model is constructed, validated, and utilised into a broader hydrogen and oxygen co-production system powered by solar-PV. A second scenario tests the compatibility of the no-degradation trend with reference material and then investigates the effects of including degradation modelling, showing only a 1.47% increase in levelised cost of hydrogen (LCOH). Subsequent scenarios include determining that byproduct oxygen utilisation becomes beneficial for a scenario with rated electrolyser power of above 35 MW, and the observations related to stack replacement strategies are discussed. Under hypothetically higher degradation rates, detriment to gas yield and LCOH is around 5% for average operational degradation rates of 15–20 μV/hr, and around 10% for 30–40 μV/hr, compared to around 2% for the model baseline average rate of 5.23–5.26 μV/hr.