What are Air Source Heat Pumps?
An Air Source Heat Pump is a highly efficient way to generate your own heat and hot water using stored energy in the air (and Air Source Heat Pump) or the ground (a Ground Source Heat Pump).
The heat pump can be sized to be suitable for individual properties, a number of properties in a district scheme, or for commercial buildings including community centres, schools, and leisure centres.
How does an Air Source Heat Pump work?
An Air Source Heat Pump extracts energy from the outside air in the same way that a fridge extracts energy from its inside. The heat pump then transfers the energy as useful heat to the property, where the heat is required.
The key benefit of an Air Source Heat Pump is that it typically produces between 2 and 3kWs of useful heat from every kW of electricity used to operate the heat it.
Things to consider when thinking about Air Source Heat Pumps as a heating solution
- Space is a key consideration. Some manufacturers have both an external unit (the fan) and an internal unit, this is called a split system, where the external unit is similar dimensions to an air conditioning unit (c. W:950mm; D:330mm; H:740mm) and the internal unit about the size of a conventional gas boiler. In mono-bloc systems where there is only an external unit the fan is slightly larger than a split system’s. For all Air Source Heat Pumps you will also need a compatible hot water cylinder and space, either in the property or in the plant room.
- Air source heat pumps are not considered ‘Permitted Development’ and as such will require Planning Permission. Typically it is a requirement for planning permission on the noise level and the visual impact of the external unit. Details of planning permission depend on the local authority, typically taking 4 weeks to gain.
- Is the property off the gas-grid, meaning your main heating system is not a gas central heating system? An air source heat pump will typically offer lower CO2 emissions and offer a reduction in energy bills in comparison to any existing electric, LPG, or coal heating system .
- Is the property well insulated? A heat pump circulates the water round the radiator system or underfloor heating system at a flow temperature of between 35-55˚C, which offers a more gradual type of heat than a gas boiler that circulates water round the system at 82˚C. As a result it is very important that heat loss in the property is kept to a minimum, and it is recommended that the property has good levels of loft or wall insulation.
- As a heat pump is thermostatically controlled it will heat each room to the programmed temperature. With the lower flow temperatures you may need to increase the size of some of the radiators in, to ensure the heat pump works most efficiently. That would be determined by a technical survey.
- For a district heating solution, you will also need to consider how piping will be run from the plant room to each individual property.
What funding is available for Air Source Heat Pumps?
For individual heating systems for one property the Renewable Heat Premium Payment is available. A £850 voucher can be claimed through the Energy Savings Trust, you meet certain criteria. For more information click here.
It is planned that a Renewable Heat Incentive will be available for air source heat pumps from October 2012, the details of this are yet to be announced. For more information click here.
Where have Air Source Heat Pumps been successful?
Toryglen, social housing scheme
British Gas is installing the largest one-site air source heat pump installation in the UK. We are offering two solutions across 6 tower blocks and a total of 232 properties. Four of the tower blocs will receive a community heating system and the remaining two will receive one heat pump per property installed on a communal balcony. The project will reduce each property’s CO2 emissions by around 45 tonnes of CO2 over a 20 year period.