Domestic RHI 

Domestic RHI ends on 31/03/2022 and has been replaced by the boiler upgrade scheme.

Air source heat pumps (ASHP)

Utilising the free renewable heat taken from the air, air source heat pumps can be installed internally or externally. The more efficient the heat pump, the more renewable heat will be produced. Initially the domestic RHI only covers ASHP that heat water – i.e. air to water.

Advantages

  • Lower fuel bills and carbon emissions
  • Ideal for properties with limited space
  • No need for fuel deliveries
  • Provides heating and hot water
  • Requires little maintenance

Disadvantages

  • Lower efficiencies than ground source heat pumps
  • Delivers lower temperatures than traditional boiler, but for much longer periods
  • May need to be on constantly throughout the winter
  • Only suitable for well insulated homes

Ground and water source heat pumps (GSHP)

The renewable heat is taken from the ground or water and is suitable for properties with access to open or large gardens, or additional land. Installations can be completed via a borehole method – where a small hole is drilled into the earth to pick up geothermal heat – or the ground loop method – where ground loop pipes are buried in channels up and down the garden / land.

Advantages

  • Lower fuel bills and carbon emissions
  • Higher efficiencies than air source heat pumps
  • Doesn’t require fuel deliveries
  • Provides heating and hot water
  • Requires little maintenance

Disadvantages

  • Requires ample land or suitability for boreholes
  • Delivers lower temperatures than a traditional boiler, but for much longer periods
  • May need to be on consistently throughout the winter
  • Requires boreholes or trenches to be dug
  • Only suitable for well insulated homes

Biomass boilers and wood pellet stoves

You can install either a biomass-only boiler, fueled by wood pellet, wood chip or logs, or a biomass pellet stove with a back burner (this includes boiler stoves) and these will be eligible for the Domestic RHI. Ideal for properties with their own wood supply or for those with good access to replenish the wood fuel.

Advantages

  • Lower fuel bills and carbon emissions
  • Wood fuel is cheaper than gas or oil
  • Use your own wood supply
  • Available with logs, pellets or chips
  • Potential fuel savings of £100 per year if replacing a gas boiler, or £580 per year if replacing electric

Disadvantages

  • Property requires access for wood fuel deliveries
  • Wood fuel prices may vary

Solar thermal (hot water)

Using free energy from the sun to provide hot water, solar thermal flat plate panels or evacuated tubes, work all year round to reduce your energy bills and CO2 emissions. A boiler or immersion heater will be needed to top up the water temperature during winter months. You'll need around 3-5 square metres of roof space which faces east to west through south and receives direct sunlight for the main part of the day. The panels don't have to be mounted on a roof: they can be fixed to a frame on a flat roof or hung on a wall.

Advantages

  • Lowers fuel bills and carbon emissions
  • Provides hot water all year round
  • Can be installed on a roof or hung on a wall
  • A choice of flat plate collectors or evacuates tubes
  • Solar energy is completely free

Disadvantages

  • Requires suitable roof orientation
  • Domestic RHI payments are only made when using solar thermal for domestic hot water (DHW), not when using for central heating contribution

Which heat pump is the best for you?