Techno-economic comparison of ammonia cracking and methane pyrolysis for hydrogen turbine integration in clean power generation: Insights from the world's first clean hydrogen portfolio standard market in South Korea

The global transition to low-carbon energy is accelerating, with increasing interest in hydrogen (H2) turbines as a solution to the intermittency of renewable energy. A stable and efficient H2 supply is crucial, and ammonia cracking (AC) and methane pyrolysis (MP) are considered economically viable and environmentally sustainable options. This study evaluates optimal clean H2 production and power generation technologies within the South Korea clean hydrogen portfolio standard (CHPS) bidding market, considering both economic and environmental factors. An integrated H2 production and power generation system is proposed, and its economic and environmental performance is analyzed. A levelized cost of electricity analysis indicates that both the MP-integrated H2 turbine (MPHT; $0.344/kWh) and AC-integrated H2 turbine (ACHT; $0.364/kWh) fall within the CHPS ceiling price, with the MPHT being the more cost-effective option. Both technologies are environmentally cleaner than conventional power sources; however, the ACHT emits 0.16 kg CO2-eq/kWh less, making it the cleaner alternative, whereas the MPHT demonstrates greater resilience to economic uncertainties and shifts in carbon policy. Both technologies are viable within the South Korea CHPS bidding market. This study supports the development of sustainable energy policies and informs technology selection by assessing the competitiveness and feasibility of H2-based power generation.