Domestic heat pumps need to be subject to tighter regulations in order for them to deliver widespread energy savings, a report has concluded. The study, described as the most comprehensive of its kind, was compiled by the Energy Saving Trust (EST).
The EST said it decided to carry out the study, accessing data from 83 sites across the UK, because there was a general lack of data on the performance of the devices. The study called for better standards to ensure the technology consistently delivered energy savings. The trial examined 54 ground source pumps and 29 air source pumps over a 12-month period, monitoring the devices’ technical performance as well as the customers’ experiences operating the technology.
The study indicated that the properties that were likely to most benefit from the technology were homes that were not connected to the national gas network, and were currently using either oil or electricity heating systems.
Almost half of the CO2 from homes in the UK are a result of space heating, while heating water accounts for more than a fifth of domestic emissions. This type of system can therefore have a profound effect on UK emissions.
Well designed systems can operate effectively in the UK, delivering in excess of three units of heat for every unit of electricity used to pump the heat in and around the property. The report estimated that if all “off-gas” properties in the UK were fitted with a heat pump, it would save 10m tonnes of CO2 each year, and cut annual bills by as much as £1.5bn.
Prospective buildings should also be well insulated to reduce the “heat load”, the amount of heat the system needed to deliver in order to warm the property.
A number of the sites included in the study did not perform well. This is possibly due to the fact that unlike conventional boilers, that you can retrofit relatively easily, heat pumps are very, very sensitive – it is imperative they are designed to heat the relative load; if they are undersized or oversized, then the efficiencies are significantly reduced.
Interestingly the EST report, which was compiled in association with the Open University, concluded that the simplest designs often delivered the highest efficiencies, but it did say that further studies were required on an installation-by-installation basis in order to learn more about what needs to be done in the future.
The Trust is set to head a working group, including industry representatives and government officials, that will make recommendations on how training and installation standard can be improved. Heat pumps will be a crucial component of our low-carbon future, provided they perform well. It is therefore essential to conduct trials to establish best practice and perfect this technology for use in buildings throughout the UK.
The UK does lag behind the rest of Europe in respect of this technology and there are a number of differences between the European and UK heat pump markets.
In Scandinavian countries for example just one company will come and excavate the bore-hole, do the design, commissioning and plumping etc – in effect the whole thing.
In the UK, because it is an emerging market, the industry is much more fragmented so you will have a variety of contractors involved and this can raise a few issues, such as not getting a coordinated approach. The market is also more mature in the rest of Europe and installers have much more experience in installing the technology
The major other difference is that the UK has particularly old and inefficient housing stock – in Europe the designing in of insulation and ‘green’ systems has been around for decades – especially in Scandinavian countries.
Hopefully the Government will see this research and ‘manage’ the growth of this technology across the UK so that standards are maintained.