Bi-Level Design Optimization for Demand-Side Interval Temperature Control in District Heating Systems

With China’s socio-economic growth, the demand for enhanced residential comfort in northern urban areas has surged. Traditional district heating systems often fail to meet modern users’ diverse needs, leading to inefficiencies and significant heat loss. This paper investigates optimization and transformation methods for demand-side-oriented heating systems. We propose key design parameters that facilitate a shift from source-end to demand-end dominance and develop a bi-level planning model for operational scheduling. The model integrates building thermal storage and adjustable user temperature ranges to optimize multi-thermal source systems. Key contributions include identifying critical renovation parameters and establishing the relationship between temperature control range and system capacity. Results demonstrate that the optimized system provides interval temperature control for 96.02% of the heating season and increases the full-load duration ratio of heat source equipment by 29.54% compared to traditional systems. These improvements enhance operational efficiency, reduce heat loss, and better align heating provision with users’ dynamic thermal demands. This research offers a robust theoretical foundation and practical guidelines for transitioning to demand-end dominated district heating systems, contributing to more sustainable and responsive heating solutions.