Are heat pumps fit for the renovation sector?

Answer by Thomas Nowak (EHPA)

Heat pump technology has seen tremendous technological advances over the past decade. Capacities, operation efficiencies at low temperatures and the possible temperature level to be provided, all have increased. In particular the latter is interesting when it comes to the question whether or not heat pumps can be deployed outside the new build, residential sector.

Are heat pumps suitable for renovation, the sleeping giant of energy efficiency in Europe's building stock? The answer is threefold:

  1. Any building that is undergoing significant renovation and reaches the energy efficiency of a new building can be heated (and increasingly often cooled) by heat pump technology.
  2. Buildings that undergo only moderate renovation (for example replacement of windows) can be heated by heat pumps, but the case is more complex and in order to make a proper assessment, a special assessment of the energy demand after renovation should be undertaken. If the building still needs more energy than a heat pump can deliver, hybrid heat pumps (the combination of a heat pump and a peak demand boiler) are a good option that also paves the way for staged renovation. If in another renovation step in the future the energy demand of the building is further reduced and peak demand is in reach of the heat pump capacity, the boiler operation can be discontinued.
  3. Buildings in which a heat pump is planned to replace the existing boiler should in all cases be assessed by an expert. It may very well be that the building envelope is of high quality and the heat distribution system is dimensioned sufficiently to provide end-user comfort. In that case, a heat pump can be used, if not, the hybrid solution presented under #2 can be deployed.

To conclude: heat pumps are suitable in all new buildings and in an increasing number of existing ones. The technological progress allows today to reach system temperatures of 65°C efficiently – and this potential should be used to accelerate the decarbonisation of the building stock.