Heat pumps and insulation - what the UK's net-zero plans mean for your home
The government has announced its plan to wean UK homes off a reliance on fossil fuels as part of its strategy for cutting emissions to net-zero by 2050.
Part of the plan includes the Heat and Buildings Strategy, which looks at retrofitting homes with low-carbon heating and bringing in stricter energy efficiency rules for commercial buildings and newbuilds.
These are the details and how it will work:
Gas boiler replacement grants
The government confirmed a target for all new heating system installations to be low carbon by 2035.
A £450m Boiler Upgrade Scheme will be used to reach that target, but the government has insisted families will not be forced to remove their existing fossil fuel boilers.
Grants of £5,000 will be available for households in England and Wales to replace their gas boilers with low carbon heat pumps.
The grants will be available from April 2022 and will mean people installing a heat pump will pay a similar amount to those installing traditional gas boilers, according to the plans.
At the moment, heat pumps are about £10,000 to buy and install so the grant would cover half the price, but the government said it will work with industry to make the pumps the same cost as purchasing and running gas boilers by 2030.
How do heat pumps work?
There are two types: air source and ground source.
Air source pumps absorb heat from the air outside into a liquid refrigerant before compressing that liquid, which increases the temperature.
The liquid then condenses to release heat which is sent to radiators and hot water cylinders inside a home.
Ground source pumps have loops of underground pipes that have a mix of water and anti-freeze pumped around them to absorb heat naturally stored in the ground.
The mixture is then compressed inside a heat exchanger, which extracts the heat and transfers it to a pump outside a home, with the heat then sent to radiators and hot water cylinders.
How many people will benefit from the grants and is it enough?
The upgrade scheme has enough money to help homeowners purchase 30,000 new air source heat pumps each year for three years - so 90,000 will benefit in total.
The Committee on Climate Change says the UK needs more like 450,000 gas boilers replaced with heat pumps by 2025.
It is hoped the grants will drive down the economies of scale and heat pumps will become cheaper to buy and install by 25-50% by 2025 and will be on a par with gas boilers by 2030, and therefore more will eventually be bought than gas boilers.
Will heat pumps bring energy costs down for households?
Not at first when compared with gas boilers because although they use less energy to create the same amount of heating, electricity is currently three times the price of gas.
Part of the reason why it is more expensive is there are higher environmental levies on electricity, which adds 23% to energy bills while gas only has a levy of less than 2% - to subsidise renewable energy.
But the government is hoping that will switch around as more heat pumps are installed.
Will heat pumps bring carbon emissions down dramatically?
It depends. In theory, they will because they reduce carbon emissions.
However, they are only affordable compared with gas boilers if they run at lower temperatures than gas boilers (50C vs 70C).
To run at a lower temperature but still keep homes warm, houses need to be well-insulated and draft-free, which brings us on to the next point...
Is there a plan to insulate homes?
There is, but critics say not enough. The Heat and Buildings Strategy includes improving insulation in social housing and for those in fuel poverty.
This is not enough to meet the net-zero target but experts say given the current pressures on public spending, this is about as much as could be expected.
However, there is little support for homeowners or private landlords to improve their homes' energy efficiency but they will be required to.
And for councils that manage the majority of social housing, they say there is not much support - and those homes are often in the greatest need of improvement.
The plan also wants as many homes as possible to achieve EPC band C - the third most efficient - by 2035 and for the poorest homes to get there by 2030 with £1.15bn in funding between 2022 and 2025.
New homes already have to be built so they use low-carbon heating and are energy efficient, but the government plans to introduce even higher standards from June 2022 which it says will result in a 31% reduction in carbon emissions compared with current new homes.
The government is also planning to consult on whether it is "appropriate" to prevent new build homes from being connected to the gas grid in England from 2025.
Is there a plan for non-residential buildings?
There is. The aim is to reduce direct emissions from public sector buildings by 75% compared with 2017 emissions, with £1.425m being invested until 2025.
Commercial and industrial buildings in England and Wales will also be required to meet a minimum efficiency standard of band B by 2030 and a new performance-based energy rating system will be used for large buildings.
Are heat pumps the only alternative?
No. The government is looking into using hydrogen for heating but it needs to carry out research, development and planning, which it hopes to complete by 2026.