2025/07/24 by Hamza Mettali, Mettali, Hamza, François, Rousset +4
Energy · Engineering · #FOS: Electrical engineering #FOS: Mathematics #Geothermal Energy Systems and Applications #Integrated Energy Systems Optimization #Optimization and Control (math.OC) #Systems and Control (eess.SY) #electronic engineering #information engineering
paper · pdf · doi:10.48550/arxiv.2507.18204
openalex publication_date 2025/07/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The integration of renewable sources is essential for decarbonizing heat production in district energy networks. Beyond biomass-based solutions, solar thermal energy, with or without heat pumps, presents a significant opportunity. However, system performance is highly dependent on outdoor and setpoint temperatures. This study aims to optimize system design using a multi-criteria approach that considers techno-economic and environmental (CO2) factors. A Mixed-Integer Linear Programming (MILP) model is developed, incorporating temperature discretization for problem linearization and capturing key dynamic characteristics of heat generators. The model improves convergence, reducing a 19% MIP gap in 26 hours to 10% in 12 hours by dissipating 6% excess solar heat. A multi-scenario analysis under two carbon taxation levels and different CO2 emission cases revealed solar integration up to 11,932 m2 but increased gas reliance (50%) and TES losses (49%). Wood boiler inclusion reduced solar dependency, covering 45% of heat, lowered LCOH, but limited renewable penetration. Higher carbon taxes boosted solar adoption but faced storage inefficiencies, while biomass enhanced cost efficiency and system stability.