Montero Guirao, Luis Manuel Morales España, German Andres Bello Morales, Antonio Reneses Guillén, Javier 2025-11-11T12:42:51Z 2025-11-11T12:42:51Z 2025-12-01 2352-4677 https:doi.org10.1016j.segan.2025.101935 http://hdl.handle.net/11531/107073 Artículos en revistas Nowadays, most modern power systems are evolving towards a considerable capacity expansion in their energy storage and interconnection facilities. However, these great developments are not being accomplished fast enough to accommodate the high penetration of variable renewable energy sources. This situation raises demand variability, requiring more flexibility from thermal generators, especially due to their more frequent start-up and shut-down processes. Consequently, the unit commitment requires more accurate and detailed modeling while maintaining computational efficiency. This paper analyzes some of the best models to manage long-duration start-up costs according to the real fuel-consumption curves of a gas-fired generation portfolio. Moreover, we propose a tight and compact MILP piecewise formulation that enhances the resolution of start-up representations and achieves outstanding results compared to the literature benchmarks. The successful performance of this methodology is proven in several large-size case studies focusing on the medium term. Furthermore, conventional day-ahead problems are also run to demonstrate the overall competitiveness of the formulation. Nowadays, most modern power systems are evolving towards a considerable capacity expansion in their energy storage and interconnection facilities. However, these great developments are not being accomplished fast enough to accommodate the high penetration of variable renewable energy sources. This situation raises demand variability, requiring more flexibility from thermal generators, especially due to their more frequent start-up and shut-down processes. Consequently, the unit commitment requires more accurate and detailed modeling while maintaining computational efficiency. This paper analyzes some of the best models to manage long-duration start-up costs according to the real fuel-consumption curves of a gas-fired generation portfolio. Moreover, we propose a tight and compact MILP piecewise formulation that enhances the resolution of start-up representations and achieves outstanding results compared to the literature benchmarks. The successful performance of this methodology is proven in several large-size case studies focusing on the medium term. Furthermore, conventional day-ahead problems are also run to demonstrate the overall competitiveness of the formulation. en-GB Revista: Sustainable Energy, Grids and Networks, Periodo: 1, Volumen: online, Número: , Página inicial: 101935-1, Página final: 101935-12 Instituto de Investigación Tecnológica (IIT) - Finanzas Cuantitativas Tight and compact MILP formulation for a high-resolution of start-up costs in the medium-term unit commitment info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/openAccess Start-up costs; Unit commitment; Medium-term models; Piecewise linearizatio;n; Mixed-integer linear programming Start-up costs; Unit commitment; Medium-term models; Piecewise linearizatio;n; Mixed-integer linear programming