The Renewable Heat Incentive is a government initiative designed to encourage the sales of renewable heating systems by paying the purchasers of the equipment an amount to subsidise the installation cost.
Ground source heat pumps are more expensive to install than air source heat pumps so the Renewable Heat Incentive payments for ground source are larger than for air source.
The amount paid is based on the tariff in place at the time the system is installed. Once the installation is accepted on the scheme the payment will only change in line with the Consumer Price Index.
From April 2016 the tariff is 7.51 pence per kWh for Air Source heat pumps and 19.33 pence per kWh for Ground Source heat pumps.
The RHI is paid on the annual heat deman shown on the household EPC less the amount of electricity required to generate the heat which is calculated using the efficiency of the installation design.
What is a Heat Pump?
Ground source heat pumps (GSHPs) use pipes that are buried in the garden to extract heat from the ground. This heat can then be used to heat radiators, underfloor or warm air heating systems and hot water in your home.A ground source heat pump circulates a mixture of water and antifreeze around a loop of pipe, called a ground loop, which is buried in your garden.
Heat from the ground is absorbed into the fluid and then passes through a heat exchanger into the heat pump.
The ground stays at a fairly constant temperature under the surface, so the heat pump can be used throughout the year.
The length of the ground loop depends on the size of your home and the amount of heat you need.
Longer loops can draw more heat from the ground, but need more space to be buried in. If space is limited, a vertical borehole can be drilled instead.