Climate-resilient urban energy infrastructure through rail-integrated photovoltaics in land-constrained South Korea

This study assesses rail-integrated photovoltaics (RIPV) across five surface railway corridors in urban South Korea. Dense metropolitan regions need renewable energy strategies that do not compete for land. Railway corridors offer one such option because they already occupy linear public space and connect closely to traction and distribution infrastructure. We develop a multi-corridor techno-economic framework for these corridors. The framework combines GIS-based suitability screening, hourly PV simulation whose yield component is validated against Korean reference data, traction-load matching, cable-loss modelling, storage sizing, and Monte Carlo economic analysis. Across these five corridors and additional suitable track fragments, the screening identifies 28.4 km of deployable main-line track and 39,760 m 2 of installable area. This corresponds to 8.51 MW of PV capacity at a module density of 4.67 m 2 /kW and 9.95 GWh/year of generation at a capacity-weighted capacity factor of 13.4 %. Hourly matching shows a clear mismatch between solar output and traction demand. Only 62.3 % of generation is self-consumed. Of the remaining 37.7 %, 19.8 % is exported to the distribution grid, and 17.8 % is curtailed. A 0.5 kWh/kW battery reduces the unabsorbed surplus from 38.0 % to 8.5 % of generation and raises LCOE by about 10 % once round-trip losses are charged to delivered energy. Monte Carlo results show a median LCOE of 170 USD/MWh on a delivered-energy basis. With a 40 % capital subsidy, the probability of payback within 12 years rises to 68 %. These results position RIPV as a credible land-neutral option for urban energy planning.