Background

The energy landscape is undergoing a dramatic transformation. Global trends push toward improved energy efficiency, accelerated integration of renewable energy sources, and a reduction in our reliance on fossil fuels. This Annex is focused on the utilization of digitalization measures of heat pump systems to optimise the operation of heat pump-based heating systems in buildings and to create safer, more efficient, and environmentally sustainable heating infrastructures.

The predecessor projects IEA HPT Annex 57, which focused on solutions for the use of heat pumps in district heating networks of various sizes to utilize flexibility potentials in the electricity sector, and IEA DHC Annex TS4 on the digitalization of district heating provide crucial input for the annex through a possible transfer of the already developed approaches and methods. It has been demonstrated how system temperatures can be optimized through digitalization measures, thereby making flexibility options usable.

The Annex addresses these results and focuses on the secondary side optimization of heat pump systems through extensive digitalization of these systems. This is intended to lower system temperatures on one hand, which allows for a more efficient and optimized operation of the heat pump system. On the other hand, the utilization of flexibility potentials through the increased and optimized use of heat pumps in an energy system dominated by fluctuating input from renewable energies should be demonstrated.

As part of the work on this Annex, a close cooperation with the IEA Technology Coop-eration Program on Heat Pumping Technologies (HPT) and District Heating and Cooling (DHC) is being sought, specifically with the recently started IEA DHC Annex TS9 project "Digitalization of District Heating and Cooling: Efficiency and Performance Improvement through Data Integration."

Objectives

This Annex project is designed to excel in the digital optimization of heat pump systems by focusing on secondary-side components. By leveraging real-time sensor data and standardized communication protocols, the Annex aims to create a paradigm shift in how building heating and cooling systems are operated – whether for new installations or retrofits. The objective extends beyond pure technical integration to also address economic, regulatory, and socio-technical dimensions.

By putting in place a strong digital infrastructure, the project's main objective is to create awareness for opportunities for the integration of digital processes and enhance the effectiveness, affordability, and environmental performance of heat pump systems in buildings as a whole. This will combine real-world demonstration procedures with data and signals from sensors in various heat pump systems. In order to fully realise the po-tential of communication across different domains in the future application of heat pump technology, the project will concentrate on analysing appropriate protocols and standards for data integration and assisting in the removal of obstacles or silos.

Summarising following objectives will be considered within the framework of the Annex:

• Raise awareness of the advantages of integrating signals and data from several areas to ensure that heat pump systems in buildings operate as efficiently as possible.
• Looking into ways to standardise data transmission protocols and ensure interoperability between the upstream infrastructure and the components of heat pump systems.
• Evaluation of non-technical obstacles and facilitators, such as business models, legal considerations, and policy tools, for the digitalisation of secondary heat pump system processes.
• Building on findings from IEA HPT Annex 57, IEA DHC Annex TS4, and IEA DHC Annex TS9, to offer an up-to-date, cutting-edge overview of the digitalisation of heat pump systems and associated secondary-side systems in the form of R&D projects, demos, and case studies.
• Disseminate the finding of the Annex via knowledge transfer activities as:
  • National workshops and special conference contributions
  • Guidebook which will be electronically available
  • Scientific publications in journals and on conferences

Scope

The scope of the annex covers the is to apply a larger range of secondary side system digitalisation techniques to improve the efficiency of both newly installed and currently operating heat pump systems in existing buildings. The first focus is on applications in multifamily buildings.

The work of this new Annex will be focused on existing residential buildings in the participating countries, mainly from northern European countries.

Within the Annex the following challenges shall be addressed:

• Enhancing Operational Efficiency: Lowering system temperatures in a controlled manner to optimize the conversion of primary energy inputs into usable heat.
• Increasing System Flexibility: Enabling heat pump systems to adapt dynamically to the fluctuating inputs associated with renewable energy sources.
• Fostering Interoperability: Developing and harmonizing data communication protocols to break down established silos between different system components.
• Addressing Non-Technical Barriers: Evaluating challenges related to regulatory inconsistencies, fragmented business models, and issues of data standardization.

Challenges include overcoming entrenched communication silos, bridging the gap be-tween advanced digital solutions and legacy infrastructure, and ensuring that policy frameworks evolve in tandem with technological innovations – all requiring coordinated investment in research and international collaboration.

Means

This project distinguishes itself by focusing primarily on the secondary side of heat pump systems. Whereas earlier projects largely concentrated on primary control measures, the current approach targets often-overlooked inefficiencies in secondary systems – unlocking substantial latent flexibility potential through advanced sensor data acquisition and dynamic demonstration procedures. Key Research Issues to be ad-dressed are:

• Data Integration and Standardization: Establishing universal standards to harmonize data among diverse system components.
• Robust Digital Infrastructure: Ensuring the resilience, security, and real-time aggre-gation capabilities of digital systems as they scale.
• Cross-Domain Synergies: Developing methodologies to facilitate seamless communication between local building sensor networks and larger district infrastructure.
• Regulatory, Economic, and Business Challenges: Addressing non-technical barriers through innovative business models, evolving regulatory frameworks, and supportive political instruments.