Heat pumps may have a crucial role in the decarbonisation of the building stock in the EU, the uptake of renewable heating and the reduction of our dependency on fossil fuel imports for heating. Heat pumps can support EU decarbonisation efforts to phase out fossil fuels and promote low-temperature district heating systems. To realise their full potential, it is important to understand if residential EU buildings, and in particular their building envelopes, are fit for heat pump installation and deployment. Energy performance certificates (EPCs) have an important role in conveying this information, especially to building owners.

For this purpose, this study:

1. Defines an approach to measure the “heat pump readiness” of buildings, tested on 30 target buildings across the EU.
2. Assesses how a break in heating supply may affect indoor temperature and comfort period in target buildings.
3. Proposes the heat pump readiness indicator (HPRI) and ways to include it in national EPCs, including a list of policy recommendations.
4. Assumes an air-water heat-pump as the reference heat pump, with a space heating capacity of 15 W per m2 of the building floor area (defined for an outside temperature of 0°C) and supplying hot water at a temperature of 45°C.

While the concept of heat pump readiness holds significant potential to advance building decarbonisation policies and bring many benefits to EU citizens, its exact definition and the development of a corresponding indicator that is integrated into EPCs, should be further investigated before moving to practical implementation. This is essential if the EU intends to implement the Energy Efficiency First principle in the buildings sector and optimise the roll out its REPowerEU objectives, aligning short- and long-term energy security and climate targets, and ensuring that EU citizens take hold of all the potential benefits of relevant depth of renovation.

The definition of heat pump readiness (HPR) is based on the main characteristics of heat pump technology and how it is used in buildings. The HPRI estimates the extent to which a heat pump can use outside air to cover a building’s heating demand, and how this depends on the building envelope and improvements made to it. Heat pump readiness can be assessed relatively easily once the characteristics of the building envelope, climate and the reference heat pump are known. A reference heat pump is introduced to ensure implementation of feasible heat pump solutions, clear comparison of results, and analysis highly relevant for all stakeholders.

Building insulation and the climate zone have a significant impact on a building’s heat pump readiness. The better the insulation and/or warmer the climate, the higher the possible heat pump readiness. Therefore, building renovation that includes the installation of a low temperature heat distribution system can significantly increase heat pump readiness of buildings, but only up to the point when maximum share of heating energy extracted from air is reached. Hence, the importance of adequate insulation.

There are various barriers to developing and deploying the HPRI. This report provides
a broad range of policy recommendations to realise its full potential. These include
recommendations on assessment and communication, consistency between the HPRI and
EPC calculation methodologies, and technical specifications for different building types.