Air source heat pumps: your flexible friend

There are many different variants of air source heat pump technology to fit all kinds of development shapes and sizes. Two main variants dominate the marketplace.

Split systems: As the name suggests there are two parts; a wall hung unit indoors similar in size to a combi boiler and the outdoor unit. The outdoor can be positioned away from the building (up to 100m) if there are concerns about noise of aesthetics. These lower flow temperature systems are perfect when used with underfloor heating or low flow temperature radiators.

Monobloc systems: With identical heating capabilities to the low temperature split system, monobloc units, as the name suggests is all contained in one single outdoor fan unit. Perfect for homes or flats with minimal available indoor space, the units are best placed near the building and are really quick and easy to install. These units produce hot water straight out of the outdoor units necessitating the need for proximity to the building otherwise good money has to be spent on highly insulated pipe to transport the valuable hot water to the home from afar.

In both cases there is no such thing as a ‘combi’ air source heat pump so space for hot water storage will always be required.

Air source heat pumps: compliance and carbon reduction benefits

The great thing about air source heat pumps is that due to their efficient use of electricity there are big gains for SAP and SBEM energy calculations and you can make significant inroads to carbon reduction for planning condition purposes. In most cases a heat pump in a domestic premise with underfloor heating will record a 30% reduction in carbon emissions for the building energy rating compared to a gas boiler.

Air source heat pumps: running cost reductions

Costs of air source systems correctly designed and installed are for existing buildings a similar cost to mains gas fuel but for new developments savings of around 10% can be made compared to gas heating. Running costs are directly proportional to the level to which the building is insulated and the efficiency of the radiator or underfloor heating system you are installing. Air source heat pump systems for existing buildings do need careful consideration due to the lower operational flow temperatures but with some considered design can be successful without going overboard with building insulation levels.

Air source heat pumps: Government grants and subsidies

The government is also strongly supporting the installation of air source heat pumps and as a developer you can benefit most if you are holding onto the asset once developed and will essentially act as the property landlord. Under the current domestic Renewable Heat Incentive (RHI) scheme you can claim as much as £10,000 of subsidy per unit and commercially significantly more. More info can be found at Ofgem’s website.

Consumer and investor pressure is building for developers to find more sustainable solutions to reducing carbon emissions in the built environment. Air source heat pumps can in part, fill that need, be easily installed, meet compliance requirements and attract free government subsidy.

So, this spring / summer, why not consider the costs and implications of air source heating as a gas alternative on your next development? You may be more than pleasantly surprised!

If you have any questions about renewable heating systems or anything else to do with your low-energy building project, please don't hesitate
to contact the Mesh team today.