With ever growing focus on households being energy-efficient – and helping save money on fuel bills in the process – heat pumps are gaining attention.
But what exactly are they, how do they work, and what do you need to know before considering one?
What are heat pumps?
According to Jon Bonnar, managing director at Cotswold Energy Group, a heat pump transfers heat from the environment outside to provide warmth inside your home. They can also provide cooling by transferring heat outwards.
“The most common heat pumps on the market today are ground source heat pumps and air source heat pumps. Both provide warmth to homes, but obtain it in completely different ways,” says Bonnar.
“A ground source heat pump channels the consistent underground temperature of the earth and transfers the heat into your home. An air source heat pump absorbs heat from the environment, even at sub-zero temperatures, and releases warmth into your living space.”
How much energy and money could a heat pump save you?
According to the Energy Saving Trust, heat pumps are highly efficient and generally ‘produce around three times more energy than they take in’. However, they may cost more to run than certain other systems, so this will need to be factored in too.
“Savings very much depend on what system you are replacing, and whether you are combining it with other technologies like solar,” says Thomas Farquhar, co-founder and chief commercial officer of Heatio. “The Energy Saving Trust shows a guide of cost comparisons which can help with this.
“We have seen customers with combined systems – including heat pump, solar and battery – saving over 50%,” Farquhar adds. “The key focus is that a heat pump is more than three times the efficiency of a boiler, so requires a lot less energy to produce the heat needed for your home. It requires electricity to run, so the lower you can get the cost of electricity from your energy supplier or by adding solar, the more you can maximise your savings from your heat pump.”
Bonnar adds: “Once a heat pump is installed, homeowners can expect to save as much as 10% off their gas heating bills over a year. With regular maintenance, heat pumps can operate for 25 years or more, making them a smart long-term investment.”
How much do they cost to install?
An air source heat pump can typically cost from £7,500-£12,000 – and sometimes higher – while ground source heat pumps tend to cost even more. However, with the Government’s £7,500 Boiler Upgrade Scheme grant, for those eligible, the costs may come into line with a boiler installation.
“There have been examples in the press where heat pumps have been installed for less than the cost of a boiler, and in some cases for free,” Farquhar adds. “Installation cost depends on what is already installed in the property, whether you are also installing radiators or underfloor heating, how far away all the key elements are, and how big the heat pump system is. There are also more green retrofit mortgages becoming available to consumers too, which will help improve accessibility to the technology.”
Can anyone have them installed?
All kinds of homes can have heat pumps installed. However, an engineer may need to assess which type is suitable.
“Factors taken into account will include the size and age of the property, how well-insulated the property is, heating demand and the space available for installation,” says Bonnar. “Air source heat pumps are often suitable for all types of property, from larger detached homes to terrace houses, where outdoor space can be at a premium.
“Ground source heat pumps require more outdoor space to properly install, as they obtain energy from the ground and therefore are more likely to be suited to semi-detached, detached, or larger flat complexes.
“For renters, their homes will likely be suitable to install a heat pump, however, factors such as the cost and labour required for installation mean it would be at the discretion of the landlord to go ahead with the changes.”
Anything else you need to consider?
Bonnar believes it’s important to evaluate your home beforehand.
“Engineers will often conduct a pre-installation survey to evaluate the installation and advise homeowner on any upgrades needed to ensure their home is fully optimised to run a heat pump system,” he says “A survey aims to not only provide transparency on installation and costs, but also provide homeowners with a better understanding of heat pumps in general and the long-term benefits they’ll see.
“Engineers will want to ensure your home is well insulated, as this will help the heat pump perform to the best of its ability,” Bonnar adds. “They may recommend homeowners make changes to their property before installing a heat pump, particularly in older homes or those with low EPC ratings that are less likely to be insulated compared to modern new-builds. Solutions such as cavity wall insulation and adding insulation to lofts and roof rooms are likely to be recommended, to help a heat pump run more efficiently.
“Another factor is your home’s current heating system. Some heating systems may not require any upgrades at all. However, on some occasions, engineers may advise on changes such as new radiators, pipework and hot water cylinders to make sure they’re fully compatible with a newly installed heat pump system.”
