Assessing the Economic and Environmental Viability of Undaria pinnatifida Sporophylls as Sustainable Cattle Feed in South Korea

This study analyzed the economic feasibility of utilizing <i>Undaria pinnatifida</i> sporophylls (UPSs), a major by-product of seaweed aquaculture, as feed for Hanwoo cattle. It employed a partial equilibrium framework to quantify processing costs, avoided disposal costs, substitution savings from reduced grain imports, and monetized methane abatement benefits, calibrated with national statistics on Hanwoo production and feed use for 2022-2024. The analysis revealed that, in the absence of environmental valuation, additional collection, transport, and drying costs (KRW 25,714-102,857 per head at 0.25-1.0% inclusion) outweighed savings from disposal avoidance and import substitution. When methane abatement was priced under Korea's Emissions Trading Scheme, however, net benefits emerged, ranging from KRW 22,757 to 40,859 per head, with welfare gains of KRW 19,108 million at 1.0%. Sensitivity analysis confirmed a strong dependence on carbon prices: benefits were substantial at KRW 40,000 per ton of CO₂, remained positive yet relatively limited at KRW 20,000, and shifted into negative territory at KRW 10,000. These findings demonstrate that UPS feed utilization can advance climate mitigation and feed security, provided it is supported by effective carbon pricing and producer-oriented policies.