UK homes more suitable for heat pumps than expected

The research looked at diagnostic data from around 4,600 boilers to evaluate the viability of installing heat pumps with no changes made to existing radiators or insulation. It found that just under one-third could operate with low temperature heat pumps (LTHPs), while up to two-thirds of the homes would be suitable for high temperature heat pumps (HTHPs).

It’s widely believed that home upgrades are almost always necessary for heat pumps to be installed in UK homes. The team behind the new research hope their findings can change the conversation around installations and lead to wider heat pump rollout. The work was published in Building Services Engineering Research & Technology.

“The installation of heat pumps into dwellings nationally is something the government has been looking at implementing for some time but there has always been that concern over cost and the believed need for some form of upgrade to the home – whether that be changing the radiators or upgrading insulation,” said Dr Stephen Watson, from Loughborough University’s School of Architecture, Building and Civil Engineering.

“Through this research we wanted to use existing data to gauge how many homes could have heat-pumps installed without the need for radiator or insulation upgrades. Understanding this could lead to a faster roll out of heat pumps as it substantially lowers predicted cost and disruption levels, thus reducing emissions quicker. We can also gain a more accurate representation of which dwellings do need improving before they get a heat pump.” 

A 2021 study from BEIS estimated that 90 per cent of UK dwellings would require new radiators to meet peak heat load for a common maximum heat pump flow temperature of 55°C, rising to 99 per cent at 45°C. However, data from the new study showed this to be an overestimate. While few dwellings could operate at the 45°C level without upgrades, 31.5 per cent of homes could operate at 55°C or less, with 66.5 per cent ready to operate at 65°C or less.

Although the study showed that more UK homes were suitable for heat pumps than previously thought, the researchers noted that high temperature heat pumps capable of operating at 65°C are significantly less efficient than their low temperature cousins. Nonetheless, they could still play a role in decarbonising home heating.

“If there are homes where LTHPs don’t quite work then there’s always the higher temperature alternatives which we found could be installed in a significant number of the homes we assessed,” said Dr Watson.

“Personally, I think there is still more work to be done in this space and I hope it gives people a different perspective when discussing the use of heat pumps. There’s quite a lot of negative press around their use with many citing concerns over their cost, disruption and feasibility in fitting them in UK homes. However, what we’ve found shows there are many homes in which they can be installed without breaking the bank or causing too much interference.”