Co-Optimizing Integrated Energy Systems for Enhancing Thermal-to-Electric Flexibility: Modeling of Heat Flow Directions
DOI:
https://doi.org/10.52825/isec.v2i.3413Keywords:
Bidirectional District Heating, Co-Optimization, Integrated Energy Systems, Sector Coupling, Thermal-To-Electric Flexibility Coupling, Thermal-To-Electric FlexibilityAbstract
The growing integration of intermittent renewable energy sources (RESs) increases the need for operational flexibility in power systems. Conventional district heating (DH) networks, constrained by fixed unidirectional flow, offer limited adaptability. This paper presents a novel co-optimization framework that couples electricity and new-generation district heating (NGDH) networks to enhance system-wide flexibility. Mass flow direction is treated as a decision variable, enabling bidirectional operation. By incorporating nonlinear hydraulic and thermal constraints, including pressure drops, temperature-dependent heat losses, and flow-temperature interactions, the proposed formulation captures the physical reality of heat transport more accurately than simplified models. To preserve tractability, the original mixed-integer, nonlinear, and non-convex problem is reformulated using second-order cone programming, McCormick envelopes, and outer approximation methods. Numerical results show that bidirectional thermal flow control can reduce total operational costs and improve renewable integration compared to conventional unidirectional strategies.
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Copyright (c) 2026 Saltanat Kuntuarova, Mohammad Kiani-Moghaddam, Vedran Peric, Thomas Hamacher
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Bundesministerium für Wirtschaftliche Zusammenarbeit und Entwicklung
Grant numbers 57525905;57753830