1. Module overview
This module introduces the principles and practices of district heating refurbishment, with particular attention to the modernisation of legacy high-temperature systems and district-heated housing estates. It explains why many older district heating systems require refurbishment, how their original design conditions differ from current energy-efficiency and decarbonisation goals, and what technical measures can support their transition toward more efficient and flexible operation.
The module examines refurbishment measures at both network and building level, including single-pipe heating system refurbishment, hydraulic balancing, substation modernisation, apartment-level substations, heat metering, advanced control strategies and the transition toward low-temperature district heating. It also introduces economic and organisational aspects of refurbishment, including business models, tariff structures, financing questions and stakeholder considerations.
The module is primarily designed as a reusable teaching resource for educators, lecturers and trainers. It can support lectures, blended learning activities, classroom discussions, case-study work, group exercises and continuing professional development training. Students and professionals may also use the materials for independent study, especially if they already have basic knowledge of district heating systems, building services, substations and energy efficiency.
2. Main topics covered in the module
- Historical development of legacy district heating systems
- High-temperature district heating systems and their limitations
- District heating refurbishment in housing estates
- Single-pipe heating system refurbishment
- Hydraulic balancing and variable-frequency pumps
- Compact and modular substations
- Apartment-level substations and individual control
- Heat consumption measurement and billing
- Transition to low-temperature district heating
- Integration of renewable and low-energy heat sources
- Electric boilers and flexibility in district heating systems
- Predictive maintenance, monitoring and digital twins
- Business models and economic aspects of district heating
- Tariff structures, motivational tariffs and financing models
- Case studies of urban district heating refurbishment and development
- Refurbishment strategy design and prioritisation
3. Learning Outcomes (skills and competences)
Upon completion of this module, learners will be able to:
- explain the historical development, structure and operational characteristics of legacy district heating systems;
- identify common sources of inefficiency in district heating networks, buildings, substations and control systems;
- analyse hydraulic balancing challenges and evaluate technical solutions for improving heat distribution;
- assess refurbishment measures at both building and network level, including insulation upgrades, substation modernisation and advanced control strategies;
- evaluate the benefits and technical requirements of low-temperature district heating systems and renewable heat integration;
- compare district heating business models, tariff options and financing approaches in refurbishment contexts;
- develop and justify refurbishment strategies that improve energy efficiency, reduce heat losses, enhance user comfort and support district heating decarbonisation.
4. Recommended use of the materials
The materials can be used flexibly in higher education and professional training contexts. Educators and trainers may adapt the guidebook, slides, quiz questions, refurbishment exercise and economic case study according to the level, format and objectives of their own teaching.
For educators and trainers
Educators may use the module in the following way:
- Review the module overview and learning outcomes: Use the overview and learning outcomes to identify how the module fits into your course, training programme or existing curriculum.
- Select the relevant guidebook sections: The guidebook can be used as core reading material, supplementary reading or background material for selected topics. Specific sections may be assigned for independent study before or after classroom sessions.
- Use the presentation slides for teaching: The accompanying slides can support lectures, seminars and guided discussions. They may be used as provided or adapted to the local curriculum and teaching format.
- Integrate the quiz questions into teaching and assessment: The quiz questions can be used for classroom discussion, formative assessment, self-check activities or integration into local LMS-based tests.
- Use the refurbishment exercise for applied learning: The exercise can support classroom work, group activities, homework assignments or project-based learning. It focuses on the diagnosis and modernisation of a legacy district heating system.
- Use the economic case study for decision-making activities: The economic case study can support group work, stakeholder analysis, tariff design, financing discussion, poster preparation or role-play debate.
For independent learners
Students and professionals using the module independently may follow the sequence below:
- Review the introductory materials: Familiarise yourself with the historical context of legacy district heating systems and the need for refurbishment.
- Study the guidebook materials: Read the explanations of high-temperature systems, building-side refurbishment, hydraulic balancing, substations, low-temperature transition and economic aspects.
- Review the presentation slides: Use the slides to consolidate the main technical concepts, examples and refurbishment options.
- Complete the self-check quiz: Test your understanding of key refurbishment concepts, modernisation technologies and low-temperature district heating principles.
- Attempt the refurbishment exercise: Apply the acquired knowledge by diagnosing problems in a legacy district heating system and proposing a prioritised refurbishment strategy.
- Review the economic case study: Explore how business models, tariff structures, financing options and stakeholder interests influence district heating refurbishment decisions.
5. Learning materials
This section contains the reusable teaching and learning resources related to the module. The materials are primarily designed to support educators and trainers in integrating district heating refurbishment topics into higher education and professional training activities. They may also be used for guided or independent learning.
5.1 Guidebook
The guidebook contains the theoretical background, technical explanations, refurbishment principles, case studies and assessment elements covered in the module. It is intended as the core teaching resource of the module and may be used as background reading, assigned self-study material or a reference document for lectures, exercises and case-study work.
Resources
- 👁️ View online
- ⬇️ Download PDF
5.2 Presentation slides
The presentation slides summarise the key concepts, technical solutions and case-study examples covered throughout the module. They are designed to support classroom teaching, guided discussion and independent review.
The slides cover the role and historical development of district heating systems, legacy high-temperature systems, refurbishment of housing estates, single-pipe systems, hydraulic balancing, compact and apartment-level substations, transition to low-temperature district heating, heat metering and billing, business models, digital twins, predictive maintenance and selected urban district heating case studies.
Resources
- 👁️ View slides
- ⬇️ Download PDF
5.3 Module video
The module video provides a short visual introduction to one selected topic, concept or practical aspect of the module. It is designed to support the use of the written learning materials, presentation slides and related learning activities.
The video can be used by educators as part of a lecture, blended learning activity or classroom discussion, and by learners as an additional resource for guided or independent study.
Resources
- 🎥 Module video (coming soon)
5.4 Self-check quiz
The self-check quiz allows learners to evaluate their understanding of the main concepts and engineering principles presented in the module. Educators may also use it as a model for formative assessment or adapt the related question bank for their own teaching context.
The quiz includes questions related to:
- legacy district heating systems and their refurbishment needs,
- causes of inefficiency in housing-estate district heating systems,
- hydraulic imbalance and balancing valves,
- substation modernisation and apartment-level substations,
- low-temperature district heating,
- return temperature reduction,
- building-level adaptation measures,
- refurbishment decision-making.
Resources
- ✅ Start self-check quiz
5.5 Practical exercise: Refurbishment strategy for a legacy district heating system
The module includes a practical refurbishment exercise in which learners act as an engineering consultancy evaluating a district heating system serving a large prefabricated housing estate. The system includes high-temperature operation, ageing distribution pipelines, centralised substations, single-pipe radiator systems, limited metering, comfort complaints and high heat losses.
Learners identify technical problems, classify them by system area, propose refurbishment measures and prioritise the first phase of intervention. The activity supports applied engineering reasoning and can be used for individual work, pair work, group discussion or a short technical report.
Resources
5.6 Classroom case study: Economic analysis of a district heating retrofit
The economic case study presents a hypothetical mid-sized city, Energiburg, operating a 30-year-old district heating network. Learners analyse a refurbishment scenario involving a transition from high-temperature operation to lower-temperature district heating, integration of biomass, waste heat and heat pumps, major CAPEX requirements, available grant funding, carbon savings and tariff reform.
The activity asks learners to compare ownership and business models, design tariff structures, propose financing strategies, map stakeholders and consider sensitivity scenarios such as fuel price changes, demand reduction and network expansion. It can be used for group work, presentations, poster preparation, short economic summaries or role-play debate.
Resources
- 👁️ View activity slides
- ⬇️ Download activity slides
- 👁️ View activity worksheet
- ⬇️ Download activity worksheet
5.7 Question bank
The module includes a reusable question bank based on the self-check and assessment questions developed by the module authors. The resource is intended to support adaptation and reuse in higher education teaching, blended learning activities and local assessment practices.
The question bank includes:
- multiple-choice questions,
- questions organised by module topic,
- items that may be used for self-check activities, classroom discussion, formative assessment or adaptation into local LMS-based quizzes.
Resources
6. Practical application
The module focuses on applied decision-making in district heating refurbishment. The presented concepts, examples and exercises are intended to support both conceptual understanding and practical system analysis.
Practical topics covered in the module include:
- identifying inefficiencies in legacy district heating systems;
- analysing hydraulic imbalance in housing estates;
- selecting suitable refurbishment measures;
- comparing building-level and network-level interventions;
- evaluating low-temperature district heating readiness;
- discussing heat metering and billing options;
- comparing public, private, PPP and cooperative business models;
- designing tariff structures that encourage efficient heat use;
- considering funding, risk and stakeholder perspectives;
- preparing short technical or economic refurbishment proposals.
The materials are intended not only for individual learning, but also for adaptation and reuse in higher education teaching and professional training activities.
7. Further reading and references
The module materials are supported by technical references, engineering literature and case-study sources related to district heating refurbishment, housing-estate modernisation, low-temperature district heating, heat metering, business models and urban district energy development.
Key references and resources include:
- Kepka György — practical refurbishment of panel-building heating systems.
- Horváth Gábor — heat consumption measurement theory and practice.
- Technical sources on balancing valves, substations and apartment-level heat supply solutions.
- Case studies on Bunhill Heat and Power Network, Citigen, Somers Town Decentralised Energy Network, Paris district heating and cooling, Copenhagen drinking water heat recovery and dynamically distributed district heating in Helsinki.
- Additional bibliography and technical references included in the guidebook materials.
8. Feedback
Educators, trainers and learners are invited to provide feedback on the module and its potential use in higher education and professional training contexts.
Feedback may address:
- clarity and usability of the materials,
- relevance of the engineering content,
- applicability in teaching and training activities,
- suitability for independent or blended learning,
- possibilities for integration into existing courses and educational programmes,
- usefulness of the refurbishment exercise and economic case study,
- relevance of the examples for local or national district heating contexts.
Resources