Decarbonizing semiconductor manufacturing: cost-competitiveness of PV-based green hydrogen production

Hard-to-abate industries heavily depend on fossil fuels and low-cost fossil-based feedstocks, significantly contributing to energy-related CO2 emissions. Therefore, a cost-effective transition towards low-carbon solutions becomes imperative. This study investigates the cost-competitiveness of decarbonizing semiconductor manufacturing by switching from conventional grey hydrogen supply to on-site green hydrogen production in a power-to-hydrogen (P-t-H) system. A silicon wafer production facility with an annual hydrogen demand of approximately 110 tonnes is considered as a case study. An optimization framework based on a metaheuristic approach is developed for the cost-optimal design of the P-t-H system, while the ε-constraint technique is applied to investigate multiple decarbonization targets. The findings indicate that fully relying on grey hydrogen remains the most cost-effective strategy, resulting in a levelized cost of hydrogen (LCOH) of 4 €/kg but emitting 1045 tonnes of CO2 annually. As grey hydrogen consumption is limited to reduce CO2 emissions, the LCOH increases exhibiting distinct trends. For decarbonization targets up to 70 %, the LCOH steadily rises to 6.10 €/kg, while stricter CO2 emissions constraints cause a steeper increase in the hydrogen production cost, reaching 10.51 €/kg in the fully decarbonized scenario. Achieving complete decarbonization requires scaling up the P-t-H compo- nents, particularly the pressurized storage tank, which becomes essential for a reliable hydrogen supply. Grid electricity import can prevent the system oversizing, thus boosting the cost-competitiveness of green hydrogen production. Conventional hydrogen supply remains cost-efficient for grey hydrogen purchase prices up to 6 €/kg, while above this threshold integrating on-site green hydrogen production becomes beneficial.