자원·환경경제연구 ISSN:1229-9146(Print) Environmental and Resource Economics Review

This study evaluates the economic feasibility of nuclear power purchase agreement (PPA)-based hydrogen production under transmission constraints in South Korea's East Coast region by comparing the levelized cost of hydrogen (LCOH) across alternative electricity procurement schemes. Four scenarios are considered: (1) continued transmission congestion allowing nuclear PPAs for approximately 6.9 GW of surplus nuclear generation, (2) complete resolution of transmission constraints with electricity procured at the industrial tariff, (3) partial congestion remaining after planned transmission expansion and the commissioning of Shin Hanul Units 3 and 4, allowing nuclear PPAs for approximately 1.7 GW, and (4) a hypothetical scenario with full nuclear PPA supply. Sensitivity analyses are conducted for carbon prices and nuclear capacity factors. The results indicate that electricity procurement costs are the primary determinant of hydrogen production costs. The industrial tariff scenario yields the highest LCOH, ranging from KRW 9,840 to 10,353 per kg-H₂, while the partial-congestion scenario results in KRW 9,108–9,479 per kg-H₂. In contrast, the current transmission-constrained nuclear PPA scenario produces an LCOH of KRW 7,452–7,622 per kg-H₂ at an 85% nuclear capacity factor, increasing to KRW 7,901–8,122 per kg-H₂ when the capacity factor declines to 65%. The hypothetical full nuclear PPA scenario yields the lowest LCOH at KRW 5,631 per kg-H₂. The findings suggest that nuclear PPAs can improve the cost competitiveness of electrolytic hydrogen, but are insufficient on their own to achieve cost-competitive clean hydrogen. Expanding clean hydrogen deployment will therefore require broader efforts in electricity supply, infrastructure development, technological innovation, and market formation.