A new government scheme will allow homeowners to apply for a £5,000 grant to help them to replace their gas boiler with an eco-friendly heat pump.

The government announced the grants as it confirmed a target for all new heating system installations to be low carbon by 2035, but ministers insisted families will not be forced to remove their existing fossil fuel boilers.

Ending the sale of new fossil fuel boilers was welcomed as sending an important signal to the world in the run-up to key UN COP26 climate talks hosted by the UK, but experts and campaigners warned the pot of funding for heat pumps was not enough.

Heat pumps explained

What is a heat pump?

An air source heat pump looks like an air conditioning unit on the outside of buildings, and it works a bit like a fridge in reverse — using electricity to extract energy from the outside air to provide heating and hot water for homes.

Because they are extracting heat from the environment — which they can do even at low outside temperatures — they produce around three times the energy they use, making them much more efficient than a gas boiler.

How much are they?

While costs vary, installing a new system will cost around £10,000 on average.

The grants aim to make heat pumps a similar cost to boilers, although how much of the installation costs for the low carbon technology will be covered by the funding will vary.

Do you save money from running one?

While there are some "time of use" tariffs, which allow people to use the electricity for running their heat pumps when it is off peak and therefore cheaper, most people will not be saving money at the moment.

That is because, although heat pumps use much less energy to create the same amount of heating, electricity is around three times the price of gas.

Will I have to rip out my old boiler for one of these new technologies?

The government has set an ambition for all new heating systems to be low carbon from 2035, but says families will not have to remove their existing fossil fuel boilers.