Around 40% of the final energy consumption in Europe is due to the building sector. This shows the great potential for energy savings and the enormous importance of this sector for CO2 reduction and climate protection. The Implementation Working Group (IWG) on Energy Efficiency in Buildings or IWG 5 works to unlock the energy savings potential of the building sector. This includes boosting the potential of existing and new buildings.

The goals of the Energy Union strategy (COM/2015/080) include deploying highly efficient energy technologies to meet heating and cooling energy demand across Europe. To address these aspects, the IWG 5 is divided into 2 subgroups: 

  • New materials and technologies for energy efficient solutions for buildings (Action 5.1)
  • Cross-cutting heating and cooling technologies for buildings (Action 5.2). 

IWG 5 plays an essential role in:

  • setting out the measures required to achieve the energy efficiency targets in the building sector
  • identifying ongoing projects
  • proposing new activities, if needed 


To specify the targets and strategies the IWG-5 developed an Implementation-Plan, which was adopted by the European Comission in 2018 and is in action since then.

The European Commission, in collaboration with the SET Plan Steering Group and stakeholders, has produced a list of research and innovation targets for each subgroup. These targets aim to promote highly efficient material and technological solutions to increase energy efficiency in buildings.

Action 5.1 – agreed specific targets:

  • reduce the primary energy of buildings by 60% on average, while also reducing total cost of ownership and limiting the payback time to 10 years
  • develop and demonstrate market ready solutions to reduce the construction and maintenance costs of nearly zero energy buildings (NZEB) or positive energy buildings by at least 10% compared to their 2015 costs, with a view to reach a cost reduction of 15%.
  • develop and demonstrate market ready solutions to reduce the average duration of energy-related construction works by over 20% for renovation and new buildings compared to current national standard practices
  • develop and demonstrate market ready solutions to reduce the difference between predicted and measured energy performance by 10%, possibly extending to a 15% after the commissioning period. 

Action 5.2 – agreed specific targets:

1.  Heat pump systems:

  • reduce costs for small and large heat pumps by 50% (compared to 2015 market price)
  • develop prefabricated, fully integrated 'plug in and play' hybrid/multisource heat pump systems and integrated compact heating/cooling plants based on modular heat pumps. 

2. District heating and cooling (DHC):

  • increase renewable heat by 25% in a cost effective manner and without decreasing consumer service
  • reduce DHC substations’ reference costs for residential buildings by 20% (compared to 2015 prices). 

3. Micro combined heat and power (CHP)/ combined cooling, heating and power (CCHP):

  •  reduce costs for equipment and installation by 50% (compared to 2015 market price)
  • increase the energy efficiency of micro CHP/CCHP by 20% (compared to 2015 levels) by increasing operational electrical efficiency and maintaining thermal efficiency. 

4. Thermal energy storage:

  • improve performance of above ground and underground energy storage (energy efficiency, system lifetime, operation and maintenance) by 25% (compared to 2015 levels)
  • increase storage density at the system level by 200% (including pumps, valves, pipes, short-term buffer) from the current state of the art 60 kWh/m³. 

Improving energy efficiency in buildings is key to achieving carbon-neutrality by 2050. The evolution of the building sector is marked by aspects such as:

  • digitalisation of construction
  • industrialisation/standardisation of processes
  • sustainability, by observing circular economy principles
  • innovation and optimisation regarding renewable and energy-efficient systems for heating and cooling and their integration into buildings 

The IWG’s research and innovation activities support these major drivers in transforming the building.

Activities for Action 5.1 set out in the implementation plan:

  • New materials for buildings
  • Prefabricated active modules for façades and roofs or key enabling technologies for active  building skins
  • Digital planning and operational optimisation
  • Living labs - energy technologies and solutions for decarbonised European quarters and cities


Activities for Action 5.2 set out in the implementation plan:

  • Cost-efficient, intelligent, flexible heat pumps (also thermally driven) and heat pumps for high temperatures
  • Multi-source district heating integrating renewable and recovered heat sources, higher temperature district cooling and optimisation of building heating system, to minimise the temperature levels in district heating networks
  • Cost reduction and increase in efficiency of micro CHP/CCHP
  • Compact thermal energy storage materials, components and systems


Particular attention must be paid to non-technological issues, as they are equally important as technological issues. Non-technological issues include:

  • user acceptance
  • education and training of individuals/bodies
  • architectural issues
  • urban planning problems
  • synergies with the transport sector.
IWG 5 is composed of Representatives of EU countries and associated countries, Industrial stakeholders, Non-governmental organisations and Research institutes.


Participating SET Plan countries

Austria, Belgium, France, Germany, Ireland, Italy, Latvia, Portugal, Spain, Sweden, Switzerland, The Netherlands, Turkey



  • (DHC+)/Euroheat&Power
  • European Construction Technology Platform (ECTP)/Energy Efficient Building Association
  • VITO
  • European Heat Pump Association (EHPA)
  • European Geothermal Energy Council (EGEC)
  • European Solar Thermal Industry Federation (ESTIF)
  • European Association for the Promotion of Cogeneration (COGEN Europe)
  • European Turbine Networks (ETN)
  • European Technology and Innovation Platform on Renewable Heating & Cooling (RHC)
  • European Platform of Universities in Energy Research and Education (EUA-EPUE)
  • EERA Joint Programme Initiative on Energy System Integration
  • SINTEF Energy Research
  • European Building Automation and Controls Association (eu.bac)
  • European Polyurethane Insulation Industry (PU Europe)
  • Architect’s Council of Europe (ACE)