The UK government has set a target for all sectors to be decarbonised by 2050. One of the major schemes put forward to reach Net Zero is to replace gas boilers with heat pumps in all residential buildings, since energy from heating homes and cooking makes up around a fifth of the UK’s carbon emissions. Almost all of this comes from using gas.
The UK faces a unique challenge in this respect: While many countries have been installing heat pumps for decades, gas boilers have long been the default option for most homes in the UK – 80% of homes are heated using natural gas – and people are reluctant to move away from what they know.
Heat pumps are designed to efficiently keep homes at a steady, ambient temperature throughout the day, by taking heat from the ground or the air around a property, augmenting it, and moving it into the building.
The government set a target of having 600,000 heat pumps installed per year by 2028. However, only 12,981 applications for its boiler upgrade scheme – which offers homeowners £5,000-£6,000 off the cost of installing a heat pump – were submitted between May 2022 and January 2023.
It seems that consumers and installers are at an impasse; homeowners who can afford to install a heat pump struggle to find trained heat pump installers, while installers struggle to find enough customers.
Phil Hurley, chairman of the Heat Pump Association, says: “The government is going to be phasing out fossil fuel cars by 2030, they’ve got an end date, the heat pump industry doesn’t. The government has an ‘ambition’ to phase out fossil fuel boilers by 2035, which is great, but it’s not mandatory.”
Hurley adds that having a fixed date by which time the industry needs to act would give a clear route and help with investment. He also says that – like most of the building industry – plumbers are quite traditional and averse to change. However, there are over 130,000 existing Gas Safe installers who could be upskilled to work towards this challenging target.
“That’s something the HPA recognises,” says Hurley. “We’ve gone some way to try and assist that with our new training course in heat pump technology, which gives existing installers the necessary skills to upskill.”
However, John Grigg, technical training manager at heating and refrigeration systems manufacturer Viessman, adds that the biggest issue is actually cost.
“It’s not that gas engineers are not interested in coming over – there are thousands of them that are probably ready, and we’ve made it as easy as possible by removing F-Gas qualifications and adding our own umbrella scheme to help those not on the MCS (microgeneration certification scheme). They’re probably working out that they could lose income and customers if they don’t embrace heat pumps,” Grigg says.
He continues: “We’re doing all we can as a manufacturer to transition to electric heating, such as investing €1 billion in expanding heat pump development capacity and building a new heat pump factory. But government needs to create certain qualifications and incentives. Uptake isn’t going to increase with what the government is currently doing. Changes need to be made.”
In the early 2000s, the then-Labour government changed the building regulations so gas boilers would be replaced with gas condensing boilers. Recalling that transition, Hurley says: “The industry said, ‘We can’t do that’, but within a year every manufacturer was making gas condensing boilers and installers got retrained with energy efficiency qualifications. So it can be done.” He suggests mandating that every heating system must be set to run at low flow temperatures by 2028. Then, because Gas Safe installers retake their exams every five years, and a low temperature heating course would be added, the entire workforce would be retrained within five years.
“Then it will naturally become part of apprenticeships and training,” he adds. “It just needs some will to do that.”
New build home regulations were amended in 2022 so that insulation levels have been increased to combat heat loss through walls and roofs; also a mandated maximum flow temperature of 55°C was brought in for heating systems. This means that even if a new house has a gas boiler installed, the system (including radiators) is heat-pump-ready when it comes to replacing the boiler in future.
Christian Engelke, Viessmann director, says: “Whether it will actually happen or is just lip service is yet to be seen, but it’s certainly a way forward.”
But there’s a problem here too, he says. Over the winter the UK has faced power cuts; some small and others more major. This, as well as government advice to use energy-intensive items such as washing machines at off-peak times, shows that the UK’s power grid has reached breaking point.
“Can we physically add more heat pumps and electrical vehicle charging points on to the system, and how quickly will the grid be upgraded to accommodate this increase?” he asks. “There’s an indication that the whole process will take longer than expected. Plus, less renewable energy was generated in the winter, so more gas and coal power stations were switched on, meaning [grid] electricity was dirtier than they expected it to be. If the grid can’t provide environmentally-friendly electricity in the winter – when most heat pumps are used – then we are back to square one.”
For decades the UK has had cheap gas, this has changed recently due to world events, but electricity has generally been more expensive. “With the investment in wind power over the last 10 years, around 20% of green levies have gone on electricity and only about 2% on gas,” explains Hurley. “The price of wind now is cheap, but it’s dictated by wholesale gas [prices]; that needs to change.
“Then, putting in a heat pump will save money on energy bills. If the message is there and people know it’s going to save them money, then they’re more likely to change over a lot quicker.”
On the other hand, Grigg counters: “Even telling consumers about it still won’t change their minds. If they’ve got a quote of £3,000 for a gas boiler and £20,000 for a heat pump, they’ll see it as it’s the government’s duty of care to bring that cost down. I don’t think we can put that on the homeowner; they’re already paying enough with electric, gas, and everything else increasing.”
BOILERS OR HEAT PUMPS?
According to Viessmann, commercial sites, such as hotels and private schools, are going back to gas because they can’t afford electricity at 70p/kWh. And it’s not just commercial sites. A £1.8 million innovative home housing programme grant from the Welsh Government to build 42 affordable homes in Cardiff (originally specified with heat pumps) has ended up installing Viessmann premium gas boilers instead because their high modulation range means they comply with Passivhaus standards.
If building regulations grade a building to a certain level of efficiency, a gas boiler can be installed if the building meets the overall emission targets set out in the regulations.
“I think the concept of pushing people to one technology is wrong. We need to make targets which are achievable on every side and aspect of the industry so they all can grow together.”