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Air source heat pumps have been seen by some as a panacea, but in fact this isn't quite the case. As the Energy Saving Trust's field trials showed, the right specification is critical, and they are not suitable for all properties.
Key points raised by this study included the fact that new-build projects and well-insulated existing homes that are off-grid have the potential to have their running costs reduced through installing an air source heat pump. The best performance can be assured if the house is as well insulated as possible, and features low-temperature underfloor heating or over-sized radiators, as well as user-friendly controls. If correctly specified, an air source heat pump should be able to provide 100% of a home's domestic hot water, but often an electric immersion heater is installed too.
Residents should also be educated in what to expect from an air source heat pump. They will need to be aware that radiators will be warm rather than hot, and because of this the property will heat up more slowly. They should also be advised that the air source heat pump will run for longer than a conventional boiler, but will closely match the heating requirements of the house thanks to proper controls (for maximum energy efficiency).
There are also some financial incentives for air source heat pumps. The Government's Renewable Heat Incentive (RHI) has been extended to include homes, and offers a tariff to those who install certain types of renewables on their homes. Only some air source heat pumps on the market are registered under the Microgeneration Certification Scheme (MCS), and an accredited product has to be installed by an accredited installer to qualify for the RHI payments. These payments only run for 7 years, but are intended to pay for the additional capital costs of the system, over and above that of a traditional heating system, during this time.