Enhancing District Heating System Efficiency: A Review of Return Temperature Reduction Strategies
Source abstract
Abstract
This review paper provides a comprehensive examination of current strategies and technical considerations for reducing return temperatures in district heating (DH) systems, aiming to enhance the utilization of available thermal energy. Return temperature, a parameter indirectly influenced by various system-level factors, cannot be adjusted directly but requires careful management throughout the design, commissioning, operation, and control phases. This paper explores several key factors affecting return temperature, including DH network, heat storage, and control strategies as well as the return temperature effect on the heat source. This paper also considers the influence of non-technical aspects, such as pricing strategies and maintenance practices, on system performance. The discussion extends to the complex interplay between low return temperatures and temperature differences, and between operational temperature schemes and economic considerations. Concluding remarks emphasize the importance of adopting a holistic approach that integrates technical, operational, and economic factors to improve DH system efficiency. This review highlights the need for comprehensive system-level optimization, effective management of system components, and consideration of unique heat production characteristics. By addressing these aspects, this study provides a framework for advancing DH system performance through optimized return temperature management.
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Research context
OpenAlex topics: Integrated Energy Systems Optimization · Geothermal Energy Systems and Applications · Building Energy and Comfort Optimization
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Unit Energy Technology, Flemish Institute for Technological Research (VITO NV), Boeretang 200, 2400 Mol, Belgium
Thermal Systems Unit, EnergyVille, Thor Park 8300, 3600 Genk, Belgium
Department of Built Environment, Oslo Metropolitan University, 0130 Oslo, Norway
Funding
‘European Union’, the ‘European Regional Development Fund (ERDF)’, the ‘Flanders Innovation & Entrepreneurship’ and the ‘Province of Limburg’
References (100+)
Show source-provided references
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