There has been a lot of new developments regarding heat pumps lately - namely an 11.8 billion pound subsidy for them. Even this community page now has a dedicated category for them, I have one myself, but are they really future of how we heat our homes?
I recently watched a video from Roger at the Skill builders youtube channel - he raised a lot of valid points. I thought it may be worth bringing them up.
I should add that i’m very happy with my heat pump, but a lot of industry professionals are raising concern for good reason.
Installers who just are installing them for the government incentive are not doing so properly
There is an increasing number of people who are given lots of the positive marketing about heat pumps, told about all the positive things, just for the installer to get the job (and the money). They will then poorly install the heat pump, not considering all the factors you have to when installing a one.
One of the biggest examples of this is installers using existing radiators designed for use with gas or oil boilers with a heat pump. The poor client is then freezing in the winter with extremely high bills. Some houses are unsuitable due to lack of insulation and other issues, and some heat pumps are midsized leading to the backup system kicking in. Have a look at the NIBE boiler problems shown here leading to HUGE bills stacking to £2000 : youtu.be/aFO6dKJLI4E
Generally an ideal heat pump installation with require:
-Complete replacement of radiators with bigger radiators, fan assisted radiators, or ideally underfloor heating
-Insulation to be added or in some cases upgraded
-double glazing at a minimum
-draft seals on every door
-a comprehensive load calculation to work out what size of heat pump is required
-A intelligent thermostat able to regulate the flow temperature based on outdoor and room temperature combined with your insulation level , and the difference between target temperature and current temperature which is usually included
-A larger radiator supply pipe and circulator pump (to keep flow rate high) or tighter wand underfloor heating (to maximise heat dissipation)
That’s just some things that i remember considering.
You might be wondering to yourself what is the worse that would happen:
-Huge electricity bills
-The ground actually freezing due to a missized installation (ground source)
-constant defrost cycles (air source)
-Not enough heat to keep at target temperature
-Not enough hot water for general use
-Legionella disease in hot water to being heated at a lower temperature
-You don’t get the payback from the government due to poor efficiency or excess energy usage
-Flow temperatures being fixed to a certain temperature leading to poor COP (efficiency) I had this issue due to an installer
-Heat Pump to large to fit in the house
-High failure rates due to complicated nature and multiple components
-poor documentation to educate client on how to efficiently use the heat pump
Tl:dr: GET A PROPER SYSTEM DESIGNER OUT TO SPEC YOUR INSTALLATION
Next up: noise.
I was very picky about noise. I have a Mitsubishi ecodan heat pump (industry leader in quietness) thats mounted on vibration isolating feet (huge soft rubber things) and its usually very near silent, but even this, best case scenario heat pump can get to a point where you can hear the Hum throughout the house in a cold winters day (-5C or lower). Now imagine the cheaper heat pumps, directly mounted on a wall as many are due to space. That will be very load and noticeable. You might be ok with it, but i bet you’re neighbors wont, especially if your in a semi detached property. :
Should the we all be paying for someone else home heating?
One of the points roger made i thought is an interesting debate: The government said they couldn’t afford a pay rise for the NHS workers because it would cost them 1 billion a year. No wonder they cant afford it, they just dropped 11.8 billion on heat pumps. Do you think the money was well spent on heat pumps, or would it have been better doing something else?
There’s other ways of being green, without spending this much money
If we do want to use heat pumps, there’s much more effective places to put them in - commercial buildings for example. Commercial buildings won’t mind the large units inside and outside, and the noise isn’t going to be a concern, not many live near offices. Its more effective to have the units at these commercial properties. putting heat pumps in these places will be cheaper per KG/co2 compared to the residential home. Is Bulb using heat pumps in there commercial space?
Could heat pumps increase carbon footprints?
Many including me have pointed out that heat pumps can cool out homes. This is great, with the increasingly hot heatwave’s due to changing climate conditions, however, that would mean insead of a boiler running a few months of the year, the heat pump will be running almost all of the year. Most of us on the forum are with bulb or another green provider of electricity, but that doesn’t change that 38.5 per cent of out electricity is generated from fossil fuel still. WIth increased demand from heat pumps running for 24/365, will the existing renewable infrastructure be able to keep up?
What’s another alternative then?
Hydrogen boilers have been making for rapid development as of late. Unlike heat pumps, they can just replace the existing gas boilers. There are issues with them too. All the recently installed gas smart meters would need to be replaced with hydrogen compatible meters, and the hydrogen would run at a higher pressure, so the existing gas mains would need to be heavily leak checked. Hydrogen production also currently uses a lot of electricity, this does mean you have both hydrogen and oxygen however, both clean burning fuels.
What do i think?
I think that:
New builds have heat pumps installed
Current oil, LPG or storage heater property’s are well insulated and have heat pumps installed
Properties with mains natural gas converted to hydrogen with new boilers.