A Terrain-Structured Dual-Pareto Framework for Saemangeum Wind-Farm Re-Planning Under Measured Wind, Wake-Loss, and Cost-Chain Constraints

Wind-farm re-planning must reconcile wind resources, wake interactions, cable routing, foundation and installation requirements, grid access, land/water-use cost, and operation and maintenance. This study develops a terrain-structured dual-Pareto framework for the Saemangeum complex coastal site on the southwest coast of the Republic of Korea, along the inner side of its 33.9 km seawall. Stage I aggregates planning-scale points into 12 regional engineering nodes and screens them using five objectives; Stage II evaluates 43,722 layouts with 12–22 turbines inside the retained envelope. The complete 2018 wind record provides the sole full-year search and economic-evaluation basis. Under the common planning model, the selected 20-turbine, 132 MW scenario is estimated to deliver 288.7 GWh with an estimated LCOE of 184.2 USD/MWh. Relative to the 99.2 MW public proxy baseline, installed capacity rises by 33.1%, total modeled energy by 43.4%, and modeled energy per MW by about 7.8%; these are aggregate modernization-and-re-planning differences, not algorithm-only effects. In the matched eight-seed, same-technology comparison, the methods show economically comparable screening LCOE and no systematic AEP or wake-loss advantage. The dual-layer search nevertheless shortens collection cable and lowers the common terrain-adjusted CAPEX proxy in all eight seeds. The fixed layouts are also evaluated over the independently held January–July 2019 record without annualization: the main layout is estimated to deliver 159.0 GWh over 5088 valid hours, with a partial-period capacity factor of 23.7%. This held-out-period assessment does not establish annual or long-term climatic robustness.