Design and modeling of a 50 MW solar tower power plant (STPP) in Gaziantep

This study presents the design, modeling, validation, and techno-economic assessment of a 50 MW molten-salt solar tower power plant proposed for Gaziantep, Türkiye. An integrated analytical–numerical workflow was adopted in which the preliminary plant configuration was first derived analytically and then simulated in SolarPILOT and SAM. The numerical framework was verified against reported data for the Gemasolar solar tower plant before being applied to the Gaziantep case. The optimized Gaziantep design indicates that plant performance is governed by the coupled effects of tower height, heliostat-field size, and thermal-energy-storage duration. For the preferred configuration, a tower height of 178 m and a storage duration of about 8 h lead to an annual net electricity generation of 212.79 GWh, a capacity factor of 48.6%, an overall plant efficiency of 18.01%, and an LCOE of 13.35 ¢USD/kWh-e. Two design scenarios were further compared in order to evaluate whether reducing heliostat count could lower cost without materially degrading performance. The comparison shows that a moderate reduction in heliostat number slightly decreases total CAPEX, but the accompanying loss in thermal input increases LCOE and reduces overall efficiency. A sensitivity analysis also shows that CAPEX is the dominant economic driver, followed by the discount rate. Overall, the study offers a validated and decision-oriented framework for site-specific solar tower design in high-DNI regions. Beyond the Gaziantep case itself, the results provide transferable guidance on how storage sizing, tower height, and heliostat-field design should be optimized together rather than independently when both technical performance and economic feasibility are targeted.