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Heating your home with renewable energy

Heat pumps, solar panels and biomass stoves are all options for heating your home. Here's how they work.
Sarah IngramsPrincipal researcher & writer
Solar panels 451077

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?

Garden bathed in sunshine

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. For example, an air source heat pump can cost around £7,000 and solar water heating around £3,000.

The cost of renewable technology is expected to come down in future but there are also schemes and grants that can help. One of these is the Boiler Upgrade Scheme, which launched in April 2022. It offers grants of up to £6,000 for heat pumps and biomass boilers to replace fossil fuel heating systems. 

Find out more about the Boiler Upgrade Scheme.

Besides the cost of the renewable system, you'll need to factor in costs for making your home more energy efficient. Heat pumps work most effectively and economically in well-insulated homes.

Read more about the different types of insulation

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 panels cost and whether solar panels are right for your home.

Heat pumps

Air source heat pump outside a home

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.

These types of heat pumps are hydronic, which means they heat water that is then circulated around your home to provide heating as with traditional gas central heating. They can also heat water stored in a hot water cylinder for showers and hot taps.

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.

Work out whether ground source heat pumps and air source heat pumps are suitable for your home in our guides.

Air-to-air heat pumps

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, which is usually used to cool rooms in hot weather but can provide heating too.

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.

Energy storage

If you can't use all the energy from your solar panels while it's being generated 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.

Find out about different types of biomass heating, plus how to reduce pollution from your stove