Air source heat pumps have an important role to play in displacing carbon emissions when deployed in appropriate applications, said Hoval.

Recent statements by government officials and others led some to suggest, that air source heat pumps could replace traditional boilers for heating and hot water. As a company that designs and manufactures both boilers and heat pumps, we can certainly see considerable scope for heat pumps, but specifiers need to be aware of important limitations to their use in buildings and industry.

In particular, heat pumps operate at lower water temperatures than boilers, so existing radiators and other heat emitters will not emit as much heat when served by a heat pump. This will make it difficult to introduce heat pumps to many existing buildings – as the sole heat source - without considerable investment in improved thermal insulation, thereby impacting the financial viability of some upgrade projects.

It has also been estimated that between 600,000 and 1 million homes would require upgrades to their electrical network to make them suitable for running heat pumps.


However, there is scope to make use of heat pumps as part of a mixed source heating solution. In this scenario, the heat pump may be used to pre-heat water before 'topping up' by a boiler, CHP or other higher temperature heat source. In this way, the use of gas- or oil-fired plant is minimised. They can also be incorporated into ventilation systems.

There are similar issues in the industrial sector. Derek Richardson is Business Development Manager at Hoval and has been in engineering for over 30 years, working in the petrochemical field, industrial burners.

He explained: "Engineers within the industrial sector are trying to include air source heat pumps (ASPH) within their systems and processes…but are limited by the fact that most of air source heat pumps on the market only produce low temperatures which are not suitable for many industrial processes. If they try to increase temperatures, they then suffer a proportionate loss in efficiency and then it becomes a balancing act.

"We are mainly using air source heat pumps for space heating with our ventilation units where they are proving extremely suitable, providing heating and cooling into the workspace. An added benefit is of course the whole system is then classed as carbon zero. Another way to use ASHP in the industrial setting is as a means to pre-heat a process to reduce boiler outputs."

So while there is considerable potential for the wider use of both air source and ground source heat pumps, we are a long way from these becoming the dominant heat source. With its breadth of heating and ventilation products, combined with unparalleled experience, Hoval is ideally placed to advise on the optimum solution for each project.

www.hoval.co.uk