A report presented to Net Zero ministers has said heat pumps are too loud to be installed in millions of homes under the government’s own noise guidelines, prompting experts to demand further trials are completed .
As part of their commitment to Net Zero, the government has announced it wants to install 600,000 heat pumps a year by 2028.
In order to help meet this target, last month the government announced new grants of up to £7,500 for homeowners swapping their gas or oil-powered boilers for heat pumps.
However, a new report has found that most air source heat pumps are too loud for properties in built up areas as the constant hum of the outdoor units would violate noise limits set for those who wish to install one without planning permission and with a government grant.
In order to qualify for the government grant, any installations of heat pumps must meet noise regulations set out by the Microgeneration Certification Scheme (MCS) which state they should not generate a noise louder than 42 decibels within one metre of a neighbour’s door or window.
A report presented to Net Zero ministers has said heat pumps are too loud to be installed in millions of homes
Typically, an individual heat pump placed outside a home gives off a sustained hum of between 40 and 60 decibels (stock image)
But the new report, which was compiled by experts from the consultancies Apex Acoustics, Sustainable Acoustics and ANV Measurement Systems, found that none of the top heat pumps from the five main manufacturers would meet MCS standard unless they were four metres away.
It stated: ‘Without the MCS there is no BUS grant and, therefore, a likely significant reduction in uptake of [heat pumps] across England and Wales.’
Heat pumps can produce a low constant hum of between 40 to 60 decibels and typically run for long periods of the winter.
The report analyzed factsheets from various heat pump manufacturers who covered around 70 per cent of the market to see how noisy they could be and how far they would have to be placed from neighbouring properties to comply with guidelines.
Amazingly, it found that some models designed to provide a higher heat output for bigger homes could have to be placed as far as 10 metres away.
In the report, Peter Rogers, of Sustainable Acoustics, said that homeowners living in terraces, flats and tenement buildings may struggle to install a heat pump under MCS guidelines.
These properties equate to 47 per cent of Britain’s housing supply.
He also warned that some installations in semi-detached homes, which equate for 31 per cent of homes, could also breach guidelines.
The Telegraph reports that due to to this the report surmises that Welsh local authorities are bracing themselves for a ‘sharp increase’ in noise complaints in urban areas due to the pumps.
Last month, the Government confirmed heat pump grants would rise as high as £7,500
Should a homeowner wish to meet the noise regulations and still recieve grant funding the report suggests they may need to build a sound barrier which can cost as much as £5000.
Alternatively, they could choose a split system where half of the heat pump is installed within the house – however this is more expensive.
Speaking to MailOnline, Mike Foster of the Energy Utilities Alliance said the findings should prompt the government to commit to further trials on the cumulative effects of heat pump noise pollution.
He said: ‘There are concerns quite rightly about the noise emitted from the outdoor units of heat pumps and as more of these appliances are rolled out obviously the likelihood of them impacting upon neighbours grows.
‘The government are consulting about whether they should reduce the restrictions and regulations around the noise and for me that’s a backward step.
‘One of the key issues we should be looking at is the noise from a concentration of heat pumps in a neighbourhood. So if you had five or six houses in a terraced block with heat pumps for instance, all running at the same time, we don’t know how loud that noise would be.
‘This is why we should at the very least have a trial. If there was a village scale trial of heat pumps, so that every house in the neighborhood was told it had to have a heat pump we could see what happened.
‘If products are getting quieter, that is a good thing.
‘But the only way in which products continue to get quieter is if you tighten up the regulations. not relax them completely. If you relax the rules completely. then there’s no need to make these products quieter.
‘The government seem to be taking the opposite view. They seem to wish and hope that the products become quieter without necessarily providing the regulations to make them do so.’
MailOnline has approached the Heat Pump Association and the three authors of the report for comment.
Peter Rogers of Sustainable Acoustics said: ‘ This claim by the Telegraph is in inaccurate, and misleading for the public given the urgency with which decarbonisation needs to occur and with urgency.
‘The work is aiming to do this with regard for the evidence.
‘It is right to say that noise emissions are an important factor when selecting the right Air Source Heat Pump for the right location and the public can find guidance on this from the Institute of Acoustics website, to help the public make a choice that will neither disturb them or their neighbours.’
Jack Harvie-Clark from Apex acoustics said: ‘While noise is a valid concern with heat pumps that needs to be addressed, technology improvements and proper installation can mitigate noise issues in most homes.
‘The Microgeneration Certification Scheme (MCS) rules are designed to prevent disturbance. With proper siting and installation, most properties could comply with the rules, if they could identify the appropriate heat pump.
‘Our paper presented in October 2023 at the Institute of Acoustics conference demonstrates how many heat pumps are too noisy for some properties. We don’t believe that this is significantly constraining the roll-out yet, as there are so many properties for which noise is not a constraint at all.
‘UK data shows noise complaints about heat pumps are very low. The survey reported in our IOA paper suggests about 100 complaints for 300,000 installations. Proper installation is key to preventing noise issues.
‘The MCS standards provide reasonable noise limits that aim to prevent nuisance noise, rather than obstruct heat pump installations.
A Department for Energy Security and Net Zero spokesperson told MailOnline:’These claims fail to recognise that heat pumps have got significantly quieter over the past decade, with ultra-low noise emission models now available.
‘Heat pumps can be installed in the overwhelming majority of homes without the need for planning permission or additional acoustic insulation.
‘We remain committed to our ambition of 600,000 heat pumps a year installed by 2028, backed by a 50 per cent increase in the Boiler Upgrade Grant – the most generous of its kind in Europe.’