Households can receive grants worth thousands of pounds to replace their boilers with new low-carbon heat pumps from Friday. Here are the answers to some key questions about the technology.
What is a heat pump?
An air source heat pump looks like an air conditioning unit outside of buildings. It works much like an upside-down refrigerator, using electricity to extract energy from the outside air to provide homes with heat and hot water. There are also heat pumps that draw energy from the ground or water.
Because they extract heat from the environment – which they can do even at low outside temperatures – they produce about three times the energy they use, making them much more efficient than a gas boiler.
UK electricity is increasingly powered by low carbon sources such as wind, making heat pumps a clean alternative to burning gas while also reducing local air pollutants, such as nitrogen dioxide, emitted by boilers.
How many are they?
Installing a new air-source heat pump costs on average over £10,000, with a ground-source heat pump costing more than that. The government grant will provide £5,000 for an air source heat pump and £6,000 for a ground source heat pump, for homes with sufficient insulation.
VAT is also being waived for clean technology installations, as well as insulation to make homes more comfortable, which will further reduce costs. Energy company Octopus has confirmed that with the £5,000 grant it will offer heat pumps at a similar price to gas boilers.
So you need a well-insulated house to run one?
All heating technologies – including gas boilers – work more efficiently and save you money if your home is well insulated and upgrading insulation to save energy is key reducing emissions from buildings.
A recent government study found that all homes in the UK, from Victorian mid-terraces to 1960s apartment blocks, are suitable for heat pumps.
Energy experts estimate that almost a fifth of homes, or some 4.8 million, are suitable for a heat pump today, while a further 30%, or 8.4 million, require minimal modifications such as insulation of attics and cavity walls, which will also reduce bills.
Do I need to make any other modifications to my home to install a heat pump?
Since heat pump radiators operate at a lower temperature than gas, you may need to swap out some of the older single panel radiators in your home to ensure they are large enough. to heat the room sufficiently. They can normally be replaced by double or triple panel radiators which fit in the same location.
Underfloor heating works very well with heat pumps as it works at a lower temperature than radiators, so it will continue to work if you have it, or if you are doing a larger renovation you might consider the to install. It is not necessary to install this, however.
Currently, you need a water tank to heat your hot water.
How are they different for running?
The main difference is that you don’t get the immediate boost that you can get with gas, when you’re cold and you fire up the boiler. This is because a heat pump heats the water in the radiators to a lower temperature than a gas boiler, which heats up a house more slowly.
But with a heat pump, the system finds the most efficient way to keep the house at the desired, continuous temperature. You can schedule changes such as when you’re away on vacation and when you’ll be back, so the house is warm when you return.
Are you saving money by running one?
It depends on gas and electricity prices. With energy price hikes coming in April, the 84% spike in domestic gas prices will drive the cost of running a gas boiler above the cost of running an electric heat pump. , even if electricity prices also increase.
Experts estimate that households who switched from a gas boiler to a heat pump could cut their annual energy bills by £260 from April. Overall, new subsidies, reduced VAT and high gas prices mean that installing and operating an efficient heat pump is approaching cost parity with gas boilers on their lifespan, although they have not yet reached it, according to Jan Rosenow’s analysis of the regulatory assistance project.
If I don’t want a heat pump, are there other technologies that could be used to heat my home?
Prime Minister Boris Johnson has acknowledged that people are “worried about having to replace their boilers at great expense”. While he said he thought costs would come down very quickly, he also pointed to hydrogen as an alternative for heating homes.
Gas could be piped through the gas pipeline network to heat homes with new boilers that can use hydrogen instead of fossil gas. But hydrogen, made from fossil gas with technology to capture and store the carbon dioxide that would be produced, or by using renewable energy to split water, is currently an expensive option.
In cities, district heating networks play a role, which route hot water through underground pipes to bring heat from a central source, such as power from a waste treatment plant, rivers or even old mines, to a heat exchanger in the houses to provide heating. and hot water.
You may choose to install a heat pump when you’re ready, while other technologies may involve entire neighborhoods or cities having to make the change at once.
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