All the reasons to install a heat pump from cost saving to saving the planet

Some things we can do for the environment are relatively easy – like doing the recycling or avoiding using the car for short trips.

Completely restructuring your central heating system does not fall into that category. And yet the British public is increasingly being urged to consider switching over their domestic heating systems to ones powered by heat pumps.

The chief benefit of heat pumps is that they extract heat from the air or ground instead of relying on the mains gas supply. And a reduction in gas use is being heavily encouraged, because the UK, along with most other countries, plans to tackle global warming by progressing to “net zero” carbon dioxide emissions.

Heat pumps do require electricity to run, but this is a lower source of carbon emissions than gas, because the UK is increasingly using green energy sources, like solar and wind power. And even when the electricity comes from fossil fuels, heat pumps are more efficient in their energy use and so still have a lower carbon footprint.

But as well as helping to save the planet, there are other reasons to consider switching to a heat pump.

Cost savings

Saving money is often touted as a major benefit from getting a heat pump – but that isn’t guaranteed, and if it does happen, it will take several years for the higher initial outlay to be outweighed by lower heating bills.

The initial cost of getting a heat pump is usually going to be more than just replacing an old gas boiler with a new one, which for comparison, may cost about £4,000.

There are two main types of heat pumps. Air-source pumps typically cost around £14,000 to be installed, according to the website Money Saving Expert, while ground-source heat pumps can be around £30,000 as they require trenches or big holes being dug in the garden. But people can claim back £7,500 through the Government’s Boiler Upgrade Scheme.

After the initial installation, though, yearly heating costs may be lower – but it depends on several factors, particularly how efficient the new heat pump system is. That is more dependent on the installer’s nous than the brand of the pump, said Dr Jan Rosenow, an energy researcher at the University of Oxford.

With a shortage of UK heat pump installers, it is important that consumers choose someone who is an expert. “There are big differences between installers,” said Dr Rosenow.

For the average consumer, their heating bill could stay about the same, according to Octopus Energy. But if people also switch to a smart electricity tariff – where power costs less in non-peak periods – they might save £234 a year, the company has calculated.

If they also install some solar panels on their roof, their yearly heating costs should be lower still.

However those calculations are based on current electricity prices, which are arguably artificially high because of green levies on electricity bills. Any government that wants to push the adoption of heat pumps may in future shift those taxes from electricity to gas bills, said Dr Rosenow. “I would suggest if people are thinking about their next heating system, they take that into account.”

Warmer homes

Heat pumps have a reputation for leaving people with colder homes, but that is undeserved, said Charlotte Lee from the Heat Pump Association. It is true that they circulate water in radiaters at a lower temperature, at about 50C, compared with 70C for traditional gas boilers.

This may well mean that homes being switched over need to have some of their radiators replaced with larger ones. But as long as that is done, there’s no reason room temperatures should be cooler.

In fact, heat pumps can lead to warmer homes overall, said Bean Beanland, a director of the Heat Pump Federation.

While gas central heating involves radiators with hotter water frequently turning off and on, heat pumps keep radiators with slightly cooler water on for more of the time – so there is less of a temperature difference between the air next to the radiator and elsewhere. “You don’t get these hot and cold spots. What you have is a beautiful ambient heat across the room,” he said.

Giving up gas

If people have no gas fire or gas cooker in their home, then switching from a gas boiler to a heat pump means they no longer need any gas supply. “It means that a household isn’t exposed to what can be a very volatile input – as we saw clearly in the wake of the Ukraine crisis,” said Dr Injy Johnstone at the Smith School of Enterprise and the Environment.

“For governments, it’s not only about reducing carbon emissions. It’s also about domestic energy security too. You can have much more control over your electricity grid than you can over the import of something that does not occur in abundance in your shores. “

And for consumers, it means they no longer have to pay the standing charge on their gas bill, which is on average about £115 a year.

Air con

Some heat pump systems can also be used for cooling the house in summer, as well as heating it in winter. This is true for ground-source heat pumps – the more expensive version – although is not practical for air-source versions.

But a third kind of system, called air-to-air heat pumps can be used for both air conditioning and heating. In fact, these systems are already in use in many homes, having been installed primarily as the familiar air con systems that blow cool air into rooms through vents.

Just by turning a switch, they can be used for circulating warm air instead. “An awful lot of people are putting them in for cooling and then realising that they can use them for heating as well,” said Beanland.

One disadvantage of air-to-air heat pumps is that they may not have the oomph necessary for heating larger areas, so they tend to be used in flats or small houses. Or people sometimes install the system in just a few key rooms, said Beanland.

And heating the home this way would then require a separate system for creating a hot water supply – this could be a separate immersion heater, also powered by electricity, said Beanland.

Forward planning

It may be tempting to ignore the push for heat pumps, as the ban on sales of new gas boilers is not due to come into force until 2035 – and even that date is not definite.

But it could be a mistake to avoid investigating the options until your current gas boiler breaks down. Getting a ground-source or air-source heat pump installed are big jobs – and the best firms may have waiting lists that months long, said Dr Rosenow.

“The risk is it’s the middle of winter, when gas boiler breaks down and you need a quick replacement. It’s good to plan ahead and not be caught out.”