Alternative Backfill Materials for Sustainable District Heating Systems

Metamorphoses of cogeneration-based district heating in Romania: A case study

Comparative Analysis Between District Heating and Geothermal Heat Pump System

Techno-economic model for district heating systems

Promoting efficient district heating in Estonia

Machine-learning-based multi-step heat demand forecasting in a district heating system

Collaborative scheduling and flexibility assessment of integrated electricity and district heating systems utilizing thermal inertia of district heating network and aggregated buildings

This paper presents an optimal production and distribution management for structural and operational optimization of the integrated district heating system (DHS) with multiple regional branches. A DHS consists of energy suppliers and consumers, district heating pipelines network and heat storage facilities in the covered region. In the optimal management system, production of heat and electric power, regional heat demand, electric power bidding and sales, transport and storage of heat at each regional DHS are taken into account. The optimal management system is formulated as a mixed integer linear programming (MILP) where the objectives is to minimize the overall cost of the integrated DHS while satisfying the operation constraints of heat units and networks as well as fulfilling heating demands from consumers. Piecewise linear formulation of the production cost function and stairwise formulation of the start-up cost function are used to compute nonlinear cost function approximately. Evaluation of the total overall cost is based on weekly operations at each district heat branches. Numerical simulations show the increase of energy efficiency due to the introduction of the present optimal management system.KeywordsHeat GenerationMixed Integer Linear ProgrammingUnit CommitmentHeat UnitHeat DemandThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

District heating and cooling (DHC) systems play an important role under the new European Union (EU) energy transition strategy. Thermal energy networks are helping to stimulate the development of alternative technologies based on a broad range of renewable energy sources. The present study analysed the current situation of DHC systems in Spain and provides an overview of the challenges and future opportunities that their use will entail. Its objective is to assess thermal energy conversion and management from a holistic perspective, including a study of existing energy infrastructures. The focus of this study lies on Spain given the country’s abundance of natural resources such as renewable energy sources including solar energy, biomass and geothermal energy, among others, as well as its strategic location on the map of the EU. Based on the analysis of the three factors for energy conversion in a district heating system, namely resources, technology, and management, the methodology provided an assessment of the different factors involved in running a DHC system. The results show an estimated total production for DHC networks of 1448 MWth, of which 72% is supplied purely by renewable energy sources.

Fault Detection and Diagnosis (FDD) in District Heating (DH) systems is vital for improving operational efficiency. As DH networks evolve towards Fourth-Generation District Heating (4GDH), their reliance on lower operational temperatures intensifies the need for robust FDD. However, implementing effective FDD faces challenges due to the lack of labelled fault data and the complexity of DH substations. This paper introduces a novel FDD methodology using Transfer Learning (TL) to bridge the gap between faulty bearings, controlled DH substation experiments and real-world operational data. We propose a fault signature method that aligns the data to reduce the domain gap, revealing similarities between faulty bearings’ vibration patterns and Δ T readings in DH substations. The TL-enhanced models demonstrated robust performance, achieving F1 scores up to 98% on lab data and 91% on real-world operational data, respectively. These results mark a notable advancement in FDD of DH substations, as our method offers accurate fault detection and valuable insights across diverse operational contexts, ranging from valve issues, faulty sensors, wrong control strategies and normal behaviour. Notably, temperature dynamics resemble behaviour akin to faulty bearing vibrations, highlighting their potential as a critical indicator of a faulty substation, enabling more effective FDD in DH systems. • Transfer learning framework using faulty-bearing, lab-emulated district heating, and real-world district heating data for substation fault detection. • A novel daily-signature generation pipeline bridging mechanical vibration and thermal temperature patterns. • The temperature signatures exhibit high variance and vibration-like patterns when a substation is faulty, as opposed to a stable, normal operational substation. • Models achieve high fault detection performance with an F1 score of 98% on lab emulation and 91% on real-world DH substation data.

District heating (DH) is a proven heat generation and distribution technology that enhances energy efficiency and reduces carbon emissions at scale, making it a key component of sustainable energy strategies. Compared to traditional heat generation methods such as using onsite fossil-fuelled combustion boilers or electrically driven heating systems, DH offers superior environmental advantages, particularly when renewable energy and waste heat are deployed as primary fuel energy mix. To comprehensively evaluate the sustainability of DH, life cycle assessment (LCA) is widely adopted to determine environmental impacts across all life cycle stages, from material extraction to disposal. This systematic review identifies the absence of a unified, adaptable framework for LCA application in DH systems. To address this, the study proposes a structured multi-level framework, interpreting methodological diversity across component, facility, and network levels. Component-level studies offer insights into specific technologies and materials; facility-level assessments focus on operational performance and energy sources; network-level evaluations provide holistic system impacts. Aligning studies within these analytical levels enables fairer comparisons, supports cross-regional learning, and promotes methodological integration. Recurring challenges include inconsistent methodologies, varying system boundaries, and limited local data. Emerging technologies such as hybrid systems, smart grids, and energy storage remain underrepresented in LCA studies. Tools like SimaPro, GaBi, and OpenLCA are widely used, yet the rapid evolution of DH systems calls for more tailored applications. This review supports the development of standardised, yet flexible LCA practices and proposes a refined multi-level framework to guide comprehensive, context-specific evaluations. It emphasises the importance of validating approaches across diverse contexts and strengthening LCA’s contribution to the design of sustainable, low-carbon DH solutions for urban energy systems. Multi-level LCA approach categorises DH systems into component, facility, and network levels. Current LCA research on DH systems focuses on Europe, with gaps in Asia and the US. Tools like SimaPro, GaBi, and OpenLCA support detailed LCA analyses of district heating. LCA for DH systems faces challenges like data gaps, system boundaries, and variability. The proposed workflow enables tailored, actionable LCA assessments for diverse DH systems.

Dynamic response of gravity-driven flow in multi-section absorption heat pump

District heating systems (DHSs) which utilize excess heat play an important role in energy infrastructure in many European countries. In contrast to Europe, the DHS is not common and excess heat is not reused effectively in Japan. Almost all the DHSs in Japan were designed as first-generation district heating (1GDH) systems or 2GDH systems. No 4GDH systems have been introduced in Japan. The present study designs a 4GDH system utilizing excess heat from a wide area of Northern Japan and evaluates its feasibility. First, available heat amounts from two excess heat resources were calculated: waste incineration plants and thermal power plants. Second, heat demand from both residential and commercial sectors was estimated using a 1 km mesh, and a heat load curve was created for each mesh based on load curve data. Third, the DHS was designed with excess heat plants as a supply-side heat resource, and spatial information of the demand side made use of the geographical information system (GIS). Further analysis was conducted on selected DHSs in three cities in order to evaluate those systems’ feasibility based on energy efficiency, CO2 emissions, and economic aspects. The result shows that 70.5 PJ of heat can be supplied by DHS in Northern Japan, replacing imported fossil fuels such as petroleum and LPG with regional excess heat. The designed DHS could supply heat with equivalent costs compared to European countries.

Accounting for external environmental costs in a study of a Swedish district-heating system – an assessment of simplified approaches

Sustainable production and consumption are the need of the hour. Adopting the Circular Economy (CE) approach fosters sustainable business practices. Cloud computing is a new way of storage and application deployment. Cloud computing enables sustainable business processes, which in turn contributes towards the effective implementation of the Circular Approach to Business Practices (CABP). The current study aims to understand the potential of cloud computing to foster circular economy practices in Small and Medium Enterprises (SMEs). We conducted a Systematic review of 186 scholarly articles published in Web of Science (WOS), selected using the PRISMA framework. We conducted scientometric analysis on sources, authors and country level and thematic analysis to pinpoint further research areas. This was followed by a detailed literature review of the articles selected to study the concept and current practices of circular economy and an evaluation of its implementation in emerging economies. The paper proposes an integrated framework grounded in two approaches, that is, the Technology, Organization and Environment (TOE) framework and institutional isomorphism as determinants of cloud adoption and CE implementation. The proposed model explores the impact of institutional forces on the various parameters of TOE, thereby culminating in the adoption of Cloud Computing in SMEs. The study would encourage leaders and managers of SMEs to adopt cloud computing for competitive advantage and achieve a circular economy approach together. The adoption of cloud‐based applications has a great potential to foster industrial and economic progress with minimum damage to the ecosystem, furthering sustainability and achieving Sustainable Development Goals (SDGs).

Future energy systems will come with a 100% share of renewable energy and high integration of energy systems. District heating and cooling systems will be undeniable parts of the future energy systems, as they pave the bed for high-efficiency, low cost, and clean production. District heating systems may come into a wide range of designs in the future. Currently, most of the world’s district heating systems are based on the third generation design while everything in this framework is on the verge of a transition to the fourth generation. A large number of technologies for the future district heating systems has been proposed so far, among which low-, ultralow- and variable-temperature systems seem more of qualification. This study employs computational fluid dynamics to make a comprehensive examination of the compatibility of regular twin-pipes with various potential district heating schemes for future energy systems. The results show that both low- and ultralow-temperature systems could efficiently use regular twin-pipes commonly used in the third generation district heating systems, though the insulation of the pipe could be proportionally strengthened based on a techno-economic trade-off. In contrast, the results show that the thermal inertia of the pipe does not allow the variable-temperature district heating system to effectively operate when the transmission pipeline is longer than a limited length. Therefore, a regular heat distribution network may not be an appropriate host for a variable-temperature district heating scheme unless decentralized heat production units come into service.