Heating your home with renewable energy

Heating your home with fossil fuels such as natural gas, oil or LPG accounts for a big chunk of your carbon footprint. In the long term, the government plans to phase out fossil fuel heating systems.

Renewable heating systems can be pricey to install upfront but, used efficiently, can have lower running costs. Installing renewable heating, rather than relying on the grid, will reduce your carbon footprint and help protect you from future fuel price rises.

There are various different options for generating your own energy at home using low or zero carbon ‘microgeneration’ technology.

Different renewable systems are suitable for different homes. Keep reading to find out about heat pumps, solar water heating, energy storage, and biomass stoves and boilers. 

Before you make the switch to renewable energy, find out how to make your home more energy efficient.

How much does renewable heating cost?

If you're considering installing renewable heating, it's important to take a long-term view. Renewable heating is often more expensive upfront than fossil fuel heating. Air source heat pumps can cost more than £10,000, but grants are available to help.

Read more about: air source heat pump costs and savings

The Boiler Upgrade Scheme, which launched in April 2022, offers grants of up to £7,500 for heat pumps and biomass boilers to replace fossil fuel heating systems. 

Besides the cost of the renewable system, you'll need to factor in other costs for making your home more energy efficient. Heat pumps work most effectively and economically in well-insulated homes, and many UK homes don't currently have enough insulation.

Read more about how to insulate your home. 

Solar thermal panels

Solar thermal panels harness the power of sunlight to heat hot water, which is stored in a hot water cylinder or thermal store (a highly insulated water tank). These are different to solar photovoltaic (PV) panels, which convert the sun's energy into electricity. 

They could provide around 90% of your hot water in summer and around 25% in winter. You'll need another system, such as a conventional boiler or immersion heater, to provide the rest.

They're cheaper to install than other renewable systems but usually only heat water, so you’ll need another system to heat your home. However, they can be installed alongside other renewable or traditional heating systems (although they aren't so easy to combine with a combi boiler). 

They work best on south-facing roofs that aren’t shaded by trees or other buildings. Read more about solar water heating. 

You can also install solar PV panels to generate electricity and help power your appliances. You can be paid for electricity you don't use and feed into the national grid. 

Find out more about how much solar pv panels cost and whether solar panels are right for your home.

Heat pumps

Unlike other heating systems that burn fuel to create heat, air-source heat pumps and ground-source heat pumps use naturally occurring heat in the air or ground to create power and heat your home through underfloor heating or radiators. 

There are also water source heat pumps that use heat energy from a nearby body of water, such as a lake, river or large pond.

They need an electricity source to work but, when used efficiently, can cost less to run than some traditional heating systems. They can produce three to four units of heat for every unit of electricity they use. If you have solar PV panels, you can power them using the electricity you generate, making them even cheaper and greener to run.

You can also get an air source hot water cylinder to provide you with hot water only, where an air source heat pump heats water stored in a high-performance cylinder. These use less energy than traditional water heaters. There are also solar-assisted versions that can take heat directly from the sun as well as the air.

See what might suit your home with our guide on how heat pumps work.

Air-to-air heat pumps

Most of the air source heat pumps you hear about in the UK are air-to-water, or hydronic heat pumps, which means they heat water that is then circulated around your home to provide heating in a 'wet' central heating system, as with traditional gas central heating. They can also heat water stored in a hot water cylinder for showers and hot taps.

However, another type of heat pump is an air-to-air heat pump. This transfers heat from the air outside to the inside of your home through fan coil units or 'blowers' to increase your home's air temperature. This is the same as air conditioning. Air to air heat pumps can both heat and cool air depending on what you need. 

Air-to-air heat pumps can't generally be used to heat larger homes and they don't heat water for showers and taps so you would need a separate system for hot water. You may also need to add ducts or vents to move the air around your home.

Energy storage

If you have solar panels but can't use all the energy they generate during the day, you can store it to use later – either as electricity or heat – to minimise the amount of electricity you need to buy from the grid. 

You can also save money by storing energy when it's cheaper to buy, such as on a time-of-use tariff where the unit price is lower at off-peak times, and using it at peak times when the price is higher. Some tariffs even let you sell electricity back to the grid.

Energy storage options include:

• Battery storage – these are rechargeable batteries that can store electricity from your solar panels or the grid.
• Thermal stores – these are highly insulated water tanks that can store heat (from multiple sources if necessary, such as solar thermal panels or a wood-fired boiler) in the form of hot water for several hours. As well as providing hot water, they can provide a 'buffer' for heat pumps to store the excess heat they generate at times when less is needed. They can also house an immersion heater, which can be powered by solar PV panels using a diverter switch, to heat the water in them.
• Heat batteries – spare heat or electricity is stored as heat by a material that changes from a solid to a liquid when it's absorbed. The material is then changed back into a solid to release the heat and provide hot water when you need it.

Biomass heating systems

Biomass heating systems burn organic material in a wood burning stove or boiler to provide heat and hot water. They’re also called wood heating systems and typically burn wood logs, pellets or chips.

Some stoves are installed with a 'back boiler' to use the heat created to warm your whole home and water. Biomass boilers are only eligible for the Boiler Upgrade Scheme if you live in a rural area and your home is not connected to the gas grid. 

If your existing heating system works efficiently, you're unlikely to need a wood burning stove as secondary heating. They're an aesthetic choice and produce pollutants, so should be used sparingly and responsibly.

Find out about different types of biomass heating, plus more on wood burning stoves and pollution. 

Use our home energy planning service to find out more

What's right for you when it comes to making the switch to low-carbon heating and energy will depend on your home, your budget and your ambitions.

It's not easy to know what will best suit you, who to trust for accurate advice, what the costs might be and who to choose to do the actual work.

Our home energy planning service gives you the know-how to make the right decisions for improving the energy efficiency of your home according to your situation.

To start using the service, register with your name and email – if you're a Which? member it’s best to register with the same email address you use for Which? – then enter your postcode and select your address. 

The service then shows you data about your home, helps you decide on the improvements you could make and gives you ballpark costs and an idea of what you could save on your energy bills. It also checks for available grants, provides information on ways to pay and can help you find trusted installers to do the work.

The estimated costs and savings are based on your property type, size, age and location and on assumptions about the number of people living there and their energy usage, using data from Energy Saving Trust.  

Try it out: make energy efficient changes to your own home with our free home energy planning service.