The European Commission's strategic long-term vision for "A Clean Planet for All" includes the ambitious goals of achieving climate neutrality and meeting the United Nations Sustainable Development Goals by 2050. One of the key challenges in meeting these goals is the decarbonization of the building sector, which is a significant source of greenhouse-gas emissions  and one of the the single largest consumers hampering Europe’s energy sovereignty of grid energy.

The report, written through a REHVA task force, explores the potential of heat pumps, district heating, and hybrid solutions as replacements for gas boilers, which are a major source of emissions in the building sector.

This report presents an overview of the most import issues which building managers, owners, and HVAC engineers should consider when shifting from natural gas to other (preferably RES) energy generators. It describes these isues from a general point of view which is applicable in various climatic conditions and for different heating sources (including those currently under development) for heating, DHW, or other purposes. Strong emphasis is placed on energy efficiency of existing HVAC systems and retrofit measures that will be conducive to the easy transition to carbon neutral buildings in the furutre, if not already the case.