Heat Pumps ~ Get Your Facts Straight!

[@ooheaven1459]

I am convinced Roger could do a video explaining the process of paint drying and still make it essential viewing. Keep them coming!

[@Jules_Pew]

I'd watch that.

[@SkillBuilder]

Thanks, I am going to try that just for fun

[@Google_Does_Evil_Now]

​@@SkillBuilderdo it, ha ha.

[@paulfern78]

Roger is the man. Is there anything he doesn't know? I don't think so!

[@Lee.Willcox]

I'm in !

[@Exposure2life]

I like a good telling off from Roger even though I haven't done anything wrong.

[@TheZippyMark]

Unusual kink, but whatever works for you 👍

[@Daisyworld743]

Talk and chalk.

[@syrus3k]

Mini split is the way to go I reckon. They're so so much cheaper and easier to install. I live in the UK but I used to live in Australia where I had several. They're great.

[@syrus3k]

Also it did get cold over there.

[@Google_Does_Evil_Now]

​@@syrus3kplease state the city, temperature variation, weather types, etc.

[@edc1569]

No, a properly installed hydronic system lasts 60 years, mini splits, you're pulling out the whole system when one part fails every 10+ years, the high level units are awful at heating the lower levels of a room without creating all sorts of drafts. Easier to install? You have to run refrigerant lines to every indoor unit, you also have to deal with condensate from every indoor unit, often this needs pumps, drains more penetrations of the buildings insulation.

[@clarkfinlay78]

Completely agree especially if the house has solar which will cover the cooling. The only problem I see with the multi-splits is the lack of hot water generation on the majority of them and the heating being hot air so potentially low humidity in the home.

[@syrus3k]

@@clarkfinlay78 good point no hot water, I guess you could either use gas for that or just use the kettle and an electric shower? Hmmm. If it was me I would leave the gas boiler to do that. I still think they're a good idea in general, can supplement a normal central heating setup nicely

[@boyasaka]

I’ve just paid 1700 quid for a brand new Worcester Bosch boiler to be supplied and fitted And my last one lasted 20 years , so I’ll happily pay the £130 a month I pay for gas and electric, Instead of forking out 15 grand on a heat pump , that won’t heat my house as warm as my combi

[@stuartsteel1]

You can't beat the good old gas boiler. Effective and reliable.

[@esecallum]

15000 ? get lost

[@mariemccann5895]

What is a quid?

[@esecallum]

Spend 15 grand to save 300 a years ..stuppid

[@boyasaka]

@@mariemccann5895 a pound 1 quid is 1 pound

[@seantaylor9758]

I always enjoy the rants about how wonderful air/ground source pumps are. Just putting another log on the stove always feels good.

[@michaeld5888]

Not good for air quality around you. You are just dumping a lot of particles it in to other peoples lungs out of sight out of mind and your own. Gas in the home and power stations is a lot cleaner and safer and the UK produces a tiny amount of the world's CO2. We are just taking other people's problems on board as per usual. Even with current usage the wood burners produce more particulates than traffic and if everyone had one the mind boggles what state the air we breathe would be in.

[@johnburns4017]

The ground temperature can be pretty constant depending on the depth and location. Ground near the sea has different temperatures than ground way inland as the temperature of the sea greatly affects the adjacent land. As heat is extracted the ground around the heat pump's borehole pipes will get cooler. The sun wil re-heat the ground but mainly by the convection of the surrounding warmer ground. If you extract too much heat the ground can become _tundra._ This tundra will be reheated by the surrounding ground during summer. Some buildings in the USA use this tundra to cool the building in summer, reheating the ground. Some systems use two boreholes, say one at the front and one at the rear of the house. By alternating you can allow the ground to reheat one borehole while extracting heat from the other. Far more efficient than air sourced.

[@gsum1000]

That's correct. In the UK the ground temperature is a constant 7 to 8 C at a depth of about 10 feet and deeper. Water supply pipes are usually at a very shallow depth, hence SkillBuilder's confusion. Some ground heating at depth is geothermal in the UK, particularly where we have deep limestone with warm springs. His point regarding horizontal ground to water HP seems moot as they demonstably work.

[@johnburns4017]

@@gsum1000 Horizontal slinkies in trenches about 3 foot deep work better in ground with good exposure to the sun not on the shaded north side. At the time you need high temperatures the air is very cold outside, hence a problem with air sourced heat pumps. Although an average over the year is realistically the economic measure. Air temperatures will raise and lower quickly and greatly unlike the more stable ground.

[@smallfeet4581]

​@@gsum1000the ground is solid and temp minus , no sun , will heat pump still generate enough heat ? , my walls are 12-13 degrees with no heating on today

[@alanjm1234]

Convection in the ground? So you think the soil circulates?

[@johnburns4017]

@@alanjm1234 Sharpen up.

[@jfro5867]

I live in the countryside in a small hamlet. We are all on oil. No gas here. 1964 build, bungalow. A year or two after we moved in we had it cavity insulated and loft insulated (around 2008), windows and doors all double glazed, it halved our annual heating bill and I spend about £1000 a year on oil. Now. Thermostat set at 18 deg. In the summer the boiler is hardly on because it just does hot water, in winter it comes in & out maintaining the CH temperature. It works extremely well and I am more than happy with it. In new build homes I can see why heat pumps may be economically viable but in older homes never designed for them I’m not so sure, even if you can afford the cost. There’s a lot of greenwashing going on. Caveat emptor.

[@nigelbullock4411]

As a retired Surveyor I can recall a ground source heat pump installation in an Academy we built in the Telford area. Basically it didn't work 2000m of trench and pipework for nothing. It was thought the pipework was faulty but that was never proved. All classrooms were issued with temporary heating for the winter months. Great!

[@peterjones6322]

So what is your point ?

[@andrewadam9544]

just watched a review on a heat pump thats been working for one year, the guy seemed happy ? its cost him an extra £263 compared to his gas boiler use the previous year but reduced his emmissions by 2.3 ton co2 ! wonderful, im happy he's happy ! i put in a log burner stove, i saved over a thousand pound last year on gas usage and i used roughly two good sized trees that cost next to nothing as i cut and processed myself, it requires zero electric to run, i have two fans on it that run from the heat generated with no electric use ! the stove heats the whole house red hot if required :) it's an approved eco stove and almost as efficient as most new boilers and more efficient than most that are over 6 or so year old...........he cant quickly increase the heat if he comes home freezing cold ! i can. if he stood in my living room in winter watching the flames, feeling the direct heat ! he'd decomission his heat pump out and install a log stove :) and by the way an average human releases about 3lb co2 a day increasing if exercising so him and his partner jumping about inside their heat pump home doing star jumps trying to get warmer cancels out his saving that he thinks he has made :)

[@surreycountyfiddle]

Studies show that by collecting the hot gasses from Roger's Rants, huge savings could be made countrywide!

[@ilricettario]

Thanks

[@SkillBuilder]

Thank you sir

[@lnostdal]

I went with air-to-air. Way better value for money on purchase - and efficiency is much, much better too! Where I live I benefit from the cooling and de-humidification during summer too. To heat or cool several rooms I've just banged some holes in the walls and put in vents; no fancy pipes, radiators etc needed -- just simple ventilation fans. Later I'll add an heat/energy exchanger - for fresh air. oh, and in the summer - my emissions are 0 because i have solar

[@paulgardner8312]

Definatly the way to go! I have been saying this for years having seen that type of device on the continent years ago.

[@timsyoutube6051]

The argument against this is because heat pumps can run at %400 efficiency you'd be better off running the solar energy through that to heat both your home and your hot water rather than just your home. However the simplicity factor of your install negates that in my humble opinion. For most smaller homes your system is probably the ideal set up that is being completely ignored by the powers that be for some reason.

[@markbarton]

I have it on good authority for the last 5 years someone has installed / run a ground source heat pump with the source being a solar hot water panel,. Apparently runs like a dream.

[@effervescence5664]

So now it's mostly public knowledge I can finally tell you that Durants Village is the place with many issues with the heat pumps, from pre-updated building regs insulation to the Mitsubishi heat pumps being put into out houses (think the old terraced house toilets with louvered doors) freezing up due to poor air circulation and a build up on condensation. Meaning they're on defrost for quite awhile in winter and not cheap to run, costing around 2.5x what you'd expect from a normal home. Worst bit is it's sheltered accommodation for older/vulnerable people so it's basically like taking advantage of them.

[@Loopyengineeringco]

Outdoor coils freezing up is normal. The fins have larger spacing than Aircon units for this reason, and sometimes are coated with moisture repelling coating. Defrost takes 10 mins out of the hour. If it doesn't complete, it's a system design fault, not enough volume - simple as that. The coils are 15 or so degrees below ambient temp hence the freezing.

[@edc1569]

Yeah I'm surprised they even work at all.

[@effervescence5664]

@@Loopyengineeringco Sadly you fell into the same logic loop Mitsubishi techs did before visiting the site. Once you put a ASHP into a box the size of a porta-loo with only the door vented and a smaller high level vent it starts short cycling and freezing up. They're supposed to be outside in open air. Otherwise they're spending anything up to 50% of the winter months as an ice block as they're just not getting the correct air flow over the coils. It is a system design fault, the site has many. It's also not the only site in the southern counties to be like it.

[@Loopyengineeringco]

@@effervescence5664 that's a sad state of affairs. If it's Mitsubishi: there are clear guidelines in the install manual about the space requirement and layout (it can't be much more obvious 🤣). From your description, it sounds like the warranty will be void because of the poor installation. Has anyone taken it up with MCS? (Presumably the installer is on the scheme?)

[@effervescence5664]

@@Loopyengineeringco From what I know the installer wasn't on the scheme it's all down to the main contractor and what they specified for "aesthetic reasons". It's hilarious if not for the fact it's a site of vulnerable people paying electric bills!

[@paulprice5466]

Having had the house fitted out with multi-split AC units I can confirm that for heating at the moment its less than 15p per hour for the entire house. In the summer I have enough PV to entirely offset the consumption of keeping cool. The whole setup cost £3500 which is still cheaper than what I would have to put in to make an air-to-water heat pump work. Not to mention I have near instant heat and cooling I dont have to pre-plan and wait for a day or 2 to get the water temperature up. Doesnt cover hot water, thats still done with gas for now.

[@hk78901]

You don't need to wait 2 days to get the water temperature up with an air to water pump, what are you talking about

[@tatradak9781]

How and where are you getting the energy from...

[@johnburns4017]

Just to have a gas meter is over £100 per ann, before you buy the gas. £100 buys a lot of electricity.

[@uksupporter8867]

Rubbish as a unit of electricity is more than that per KWH so so you claim the whole of your house to heat is a third or 300w per hour to run , absolute rubbish

[@passais]

Thanks. I was amongst the people calling a ground based system geothermal so I learned something today.

[@owen8538]

Heat pump s are awesome even in older homes work amazing in uk

[@SkillBuilder]

Which one do you have?

[@robandchristheateam5053]

Brilliant Mr Bisby. You carry a big consumer message for common sense. POW!!!

[@flipper2392]

When I had my combi boiler installed three years ago the fitter told me heat pumps are virtually useless in homes like mine built in 60s. A neighbour has one but has stripped all walls of plaster and relined with insulation board, not sure I could be arsed with that, I doubt I'd live long enough to recoup the cost.

[@iareid8255]

Flipper, that's looking at it the wrong way. Improving the insulation makes a difference for gas\oil heating as well, it cuts running cost. Insulating so that a heat pump can be fitted is more expensive and less effective due to the lower temperatures from a heat pump.

[@JoE-sl8vp]

The ruling class are incompetant. China creates 33% of co2 we create 1%. We are not the criminals here. This will destroy us.

[@peterjones6322]

Yes let children and grandchildren to bothered about global warming.

[@JoE-sl8vp]

@@peterjones6322 Exagerrated !

[@michaeld5888]

Surely we can all transfer to the second home while they strip out the house. Net zero is surely all about people who can spend £30,000 to knock £300 a year off their heating bill and constantly tell everyone about the latter.

[@bunnywarren]

I know someone who has a mini-split based system for their house airsource heat pump. It uses the mini-split style behaviour to move a refrigerant from the outside unit indoors where the pump is located. This is then used to heat water within their system that is distributed to the radiator/underfloor heating. It has the advantage of needing a much smaller hole through the wall to the outdoor unit, which also needs far less power since it just needs a fan to move the air. The smaller pipes are also easier to insulate than water pipes, which are quite large.

[@redshift3]

yes, split system vs monobloc

[@flashback9966]

If you are luckily enough to have a river at the bottom of your garden, this is the best source of energy for a heat pump.

[@Vile_Entity_3545]

Until it freezes totally one year.

[@mikerodent3164]

@@Vile_Entity_3545 Interesting... funnily enough people on the other side of the road where I live are in that situation: Ravensbourne River in South London: their gardens literally go down to this river without any fence, embankment, or anything. But regarding your comment, I just googled "last time a river froze in england" and nothing came up. The Thames used to freeze very very occasionally. I'd be interested to know the answer. It's probably not something to scupper flashback9966's idea...

[@lksf9820]

@@Vile_Entity_3545 Rivers don't freeze in the UK.

[@MrWokyman]

Can we all chip in for some new pens for Roger?

[@14caz68]

😂

[@SkillBuilder]

I got some for my Birthday, thanks

[@TurinTuramber]

He has loads of them but is too tight to throw away the old ones. 😃

[@mikerodent3164]

@@TurinTuramber I'm not sure it's that: I think he knows that scratchy old pens make us concentrate harder ... on the appalling state of the pens at least.

[@scoobyflew]

My best friend is high up in the HVAC industry and 15 years go they put ground source head pumps into 5 terrace new build houses. All was fine in the summer, but in winter the middle house's "numbers" were way off, they surveyed the ground and found the garden in the middle house had turned to perma-frost! The ground never thawed during the winter and the pump could not extract any heat! Trial was cancelled!

[@redshift3]

inadequate design. It would have worked better if they had used a communal ground loop

[@mariemccann5895]

Superbly accurate description of the issues!

[@TheRealFOSFOR]

Just wanna tell people that cooling the house in the summer is pretty "cheap" compared to warming the house in the winter. Warming a house from 0C° to +20C° takes a lot more energy that cooling from +25C° to +20C°. oh and the heat from the sun is typically about 90% of the total heat in the ground (in England).

[@tatradak9781]

What seems odd is why isn't cold water pumped around the radiators and fans fitted radiators to increase the cool air flow...

[@fus149hammer5]

​@@tatradak9781because cold air doesn't rise.

[@tatradak9781]

it does with a fan@@fus149hammer5

[@redshift3]

@@tatradak9781 because we live in a humid climate and water will condense on the cold pipes and radiators, causing problems

[@tatradak9781]

Its for the summer time..there is no condenstaion then... @@redshift3

[@baronsilverbaron757]

I've got a Daikin Atherma heat pump and it works brilliantly. I've got my heating cranked up to 23 C

[@SkillBuilder]

What Scop are you getting at that temperature?

[@baronsilverbaron757]

?@@SkillBuilder What's a Scop?

[@danguee1]

7 minutes of my life I'll never get back!

[@SkillBuilder]

You won't get any of it back, whoever sold you that line was lying to you.

[@bordersw1239]

Had my gas boiler have it’s first major service today at 6yrs old. Total cost was £150, usual service £70. Cost me £2500 installed 6 yrs ago. My 20yr old 4 bed house is pretty efficient £685 heating and hot water last year. I wonder what the cost to change to ASHP would be as my house uses 10mm plastic pipe so would all need replacing with current heat pumps.

[@pauldavies7251]

You won't be getting any change from £20k & even more if you need extra insulation fitted, Its one great big con job

[@edc1569]

I wouldn't worry about it, you've got at least 5 more years life from that boiler before its worth looking into where the tech is.

[@somedude-lc5dy]

you sound like you have a decent system, so I think you're fine. a good rule of thumb is to never change technology unless you're already at the end-of-life of a unit.

[@bordersw1239]

@@somedude-lc5dy . LOL, something my father would have said, along with let the new adopters suffer the pain, until they iron out the faults.

[@MrMax4music]

@pauldavies7251 Haha 20k! Ground source perhaps. He'll get quotes well below 20k for air source plus he'll get a 7.5k grant towards it. He might be able to run 10mm pipe still but it really depends on having a good survey to determine these factors.

[@zacherynuk842]

I installed an air to air AC / Heat pump in my office a few years back, butane coollant so no licence required - but I did have to buy a cool flanging tool. I have been toying with the idea of installing a similar unit at the top of my stairs, with the fans outside on the kitchen extension. I am doubtful of it effectivity within my home, however. My office is a SIP build so super insulated and it all works very well....I can reduce the internal temprature during recent summers from a stiffling 50 odd C to 20 and in the in the winter warm it up cheaper than my oil radiator. House has no gas and no wet plumbing / radiators. hence my thinking - HP could just about be cheaper than wood and almost certainly cheaper than electric radiators.

[@gregmcbrien2106]

The ground temperature increases as you go deeper, not colder. As for freezing the ground, that's if the system heat transfer and reservoir is not designed right. An air to air heat pump will freeze the evaporator if the capacity is not designed right. The COP of mini splits is less than 2 in sub zero F climates, ground source, 4. Twice as efficient

[@neilfox4721]

Roger, am I missing something here, you can pay £3k for a new efficient gas boiler that fits on the kitchen wall, is warranted for 10 years and costs about £80 a year to service. The alternative is having a heat pump journey with surveys and remedial work that requires a large spare room or garage to store all this equipment and an outside unit. You then wait and hopefully it all works. Not to mention the installation and servicing costs. All this so instead of burning gas at home efficiently you burn it at a power station to convert the energy into electricity that costs four times more per unit than gas.

[@justinterested5819]

1) You miss that Gas (and the supply lines) costs money as well 2) A Heat Pump isnt that big. 3) You only burn it efficiently when you have it properly installed. If your installation is wrong (little insulation/low radiator sizes/high temperatures), you dont heat efficient at all, just like with heat pumps 4) Only a part of the electrical power comes from Gas Power Plants. A large portion of the electricity already comes from sources that are not fossil 4B) If the government dosent care for emissions anymore, it can always replace the electricity generation with local coal, what is cheaper than imported Gas (and also is easier to import from friendly nations than Natural Gas). Nuclear Power can also be used if available with no big losses 5) You also get 4 times the amount of heat energy out compared to gas, so they are equal in that sense. Also, you can save additional money by using special tariffs that compensate you for being flexible.

[@zogzoogler]

perhaps missing that not everyone in the UK is on mains gas, so you either have LPG, oil, or logs coal and a back boiler. So to update an old oil system may include a bunded tank (£1500), boiler £3-5k, then rads etc may be 40+ year old. Grants for people on pension credits in North Yorkshire for example work on hierarchy of 1. off gas network? 2. Energy rating of property 3. attributes of property. So if your oil system is 20 years old would you go for oil or heatpump?

[@steventonkin9689]

Thanks Roger a very common sense clear explanation 👏

[@marko7425]

Two thirds of houses in Norway use heat pumps and that's in temperatures of -25 degC. Good clear video, thanks Roger.

[@johnburns4017]

Electricity costs in Norway are cheaper than the UK.

[@michaeld5888]

Setting up these systems in a country with a tiny population and electricity produced mainly by hydropower is of little relevance to the UK. The insane UK plans have no contingency that can be seen for dunkelflaute which is hardly a problem in Norway so your heat pumps will keep running. Keep supplying us with gas though as without it we will be doomed with our closing down our own production facilities to buy in from abroad.

[@davidj2448]

Im sure heat pumps work for some buildings in the uk. But you still cant beat a nice powerful gas boiler 🔥

[@yngndrw.]

Of course you can, an oil boiler. :)

[@james.telfer]

Iceland: hold my beer while I tap a volcano... 😁

[@Pain_in_Diaz]

Yeah you can. Gas boilers are...at best 85% - 95% efficient. Heat pumps are on average 300% - 400% efficient.

[@davidj2448]

@@Pain_in_Diaz rubbish

[@Pain_in_Diaz]

@@davidj2448 it isn't though

[@PSNvjimmy]

Oh Roger, you know what you’re doing to get views. Well done :)

[@denissul8532]

That is why no situation can't made worse by government

[@stevek3036]

Excellent tutorial - I learnt a lot about ground source considerations and how the extraction of 'heat' will take time for it to be replenished - something you won't hear from the companies selling this type of heating?

[@LeighPage-v9p]

These are great for the UK, wish I had had one when I lived there. Yes, I know this is about the UK, but in many US states you simply couldn't get away with a heating only system, fantastic insulation or not you would still need cooling.

[@Doug....]

Well explained Roger. Thanks 👍👍

[@nicksimmons7234]

Daily Mail readers love Roger.

[@Doug....]

Nick ? @@nicksimmons7234

[@johncranwell3783]

Well put…. The best six for the nation I’ve seen for the masses so far

[@DuncanEdwards.]

I still love our two mini split systems

[@markingle8487]

Same here; after being very pleased with our first mini split, we had another 'hyper inverter' unit installed. Yes, no grants but it was VAT free and in the scheme of things the cost wasn't huge.

[@englishcitystone1663]

Brilliant delivery, good information, thanks Roger.

[@OzarkGenerations]

You've solved global warming! Good job.

[@uksupporter8867]

Gas is the best way to go boilers are cheaper to buy by thousands

[@mjoelnir1899]

A first time I come across in one of those videos, where some body gets the difference between ground sourced and geothermal right. I want to add, that you go geothermal, in areas where geothermal does not reach the surface, when you go deep. I talk about going at least 400 m for hot water, but most often down to 1,000 to 3,000 m. The surface geothermal was already used by the Vikings. As such boreholes are expensive, it is done most of the time for district heating. Here in Iceland most of the boreholes, with reasonable power are about 2,000m, about 5 kW in a good working borehole.. In the first step you extract electrical energy using the steam and the water cools down to 90¨C. That water is than used for district heating..You use the same equipment drilling far hot water as drilling for oil. You will find geothermal energy in a lot of countries and areas at a reasonable depth. Always when you go deep enough. Were you have wet rock you can extract the heat by pumping up the hot water or you are getting steam. With non water bearing rock or dry rock, you have to introduce water through one hole, crack the rock and pump hot water or steam up through another hole. Most of Iceland, 95% of the houses including industrial sites are heated by geothermal. All in all over 60% of all energy used in Iceland comes from geothermal.

[@Tom-Lahaye]

Despite not getting a grant for split air conditioners it was still much cheaper for me to go this way to get away from natural gas. The argument that it doubles energy use doesn't completely hold ground, at least for us living in climates like the UK and western Europe have. In general the amount of energy needed for cooling in the summer is much less than for heating during the cold seasons, provided that the house is reasonably insulated and doesn't have huge windows or a conservatory on the south side of your house or have good sun blinds on these. My house is well insulated now, we had a warm summer here in the Netherlands this year, but I needed cooling for less than a week in total, and having the aircon on just a few hours per day was sufficient to keep temperatures inside below 25°C.

[@JamesandRibble]

I have a ground source heat pump. The water temp in the hot water system is set constant all year.

[@ATomRileyA]

Great explanation. I think the biggest problem will be the rising cost of electricity used to run the heat pumps, say in 10 years do you think the electricity cost is going to go up or down, with all the extra load of EV's and such i think the price will rise more unless some miracle happens with power generation or battery storage. Be nice if you had a heat pump to work alongside a normal gas boiler so you can have the best of both worlds. I would have thought it was possible although i think the heat pumps run at a much lower temp. Will be interesting to see how it all works out over the next 10 or so years.

[@johnh9449]

Fair comments Rodger. The good thing about ground source is that you can store energy from season to season - as opposed to air source with battery which can only store from one day to the next. The ground thermal mass is a much bigger store. But, with tariffs now available it's possible to store your excess solar panel energy in summer in the form of export cash in your electricity account and use that as cheap rate import in winter for use during the day with your air source heat pump. That can be more profitable. The combination of solar PV, battery and heat pump can save you 75% compared to a gas boiler and the tariffs avoid the installation expense of ground source.

[@edc1569]

Can you really store heat in the ground? Isn't it one massive thermal sink?

[@MichaelFlatman]

How do you put the heat into the ground without cooling your house, do you then heat your house with electric heat? must be an expensive operation

[@johnh9449]

@@edc1569 So I've heard that you can warm up the ground in summer with your excess energy and suck it back out in winter, this can be done with your heat pump operating in reverse as air conditioning in summer with free energy coming from solar panels - the ground being so much bigger a thermal mass and so much slower to change temperature. Compared to a battery, say 15kWh 24h store, the ground must be 365 times that or 5,400kWh equivalent.

[@johnh9449]

@@MichaelFlatman It's the excess heat from free solar energy that you can store, raising the ground temperature slightly, then extract that in winter when needed and with the heat pump being very efficient in the order of 300% to 500% efficient it works out to be very cost effective.

[@crabby7668]

@@johnh9449 what's to stop your neighbour extracting that heat if they are similarly equipped? You have no way to stop the heat energy flowing to their collection pipes if they are using the heat faster than you. I would suggest that much of the benefits of this type of equipment are sold on the basis that only you have the system. If every property, particularly in cities, had ground source heat pumps then the heat source is going to be depleted fairly quickly. The reason the ground stays a reasonably constant temperature is because it is not a very good heat conductor. Thus the quicker you extract heat, the more it will struggle to replace that heat either from below or from solar radiation above. So the more systems that you have close to each other, the less effective they will be, particularly in extreme circumstances. The same will occur with air source when everyone has got one. They extract heat from the environment which makes it colder. You are relying on the environment to replenish that heat from beyond the immediate location. The more pumps there are in a particular location the larger the area that will be needed to replenish the local heat, thus you are effectively cooling the local environment. Whether there are detrimental effects from that remains to be seen. Although you can imagine if outside temperatures normally hover over 0c in winter, widespread heat pump installation might push the local temperature below 0c more often.

[@kosobek]

I like my mini split cooling my home office in the summer. 😎Reckon best to install it before gov does something stupid and bans them.

[@ColinH1973]

What about brown source? It's available on HP.

[@chris-non-voter]

I have two ASHPs in my 2 bed flat. I only use one at a time. It keeps my whole flat lovely and warm. It comes on at 7am and goesnoffbat 11pm. I'm electricity only, my electricity cost is £73 for all my electricity per month during the winter. I love it. Compared to my underfloor heating the ASHP saves me about £200 per month.

[@johnhunter4181]

You should vote. Me too! 5 bed detached, 2 a/c units - total energy bill £120 in December.

[@solentbum]

The most important FACT, Insulate!! Whatever your heating system.

[@TheSockWomble]

Had an old oil burning combi boiler on its last legs we are out in the sticks detached bungalow concrete block with render with cavity insulation. Had quotes for Airsource heat pumps and costs were about 12-13 k but for the grant you need a valid EPC survey with NO recommendation for insulation up to latest building regs ! We have planing permission for a loft conversion so waste of money putting loads more insulation in the loft just to get a grant ! Dodged a bullet I think so had an outside Worcester Bosch system boiler with a 300 litre cylinder installed all for about 6k at least we can now stay warm this winter and not worry about sky high electricity bills!

[@MrMax4music]

Not worth spending 100 quid on 3 or 4 rolls of loft insulation to get a £7500 grant? Errr

[@ian4iPad2]

Pity about the lack of support for reverse cycle HPs. Probably welcome the AC when the climate really warms up, which it inevitably will. AC could still run on “green” energy - is there a problem?

[@james.telfer]

Well, pumping hot air into an already high air temp just makes it hotter outside? And since no machine is 100% efficient, you're adding more waste heat from its operation. Better to have well insulated houses (warm in winter and don't heat up in high summer). Even my 30's semi stayed much cooler last summer just by closing the curtains in the day and venting in the cool of the morning. +10C delta to outside temps on those days.

[@iareid8255]

Heat pumps don't run on green energy, much as the government want you to think that. They run on more or less due to that being the source of generation that reacts to extra grid load. Renewables and nuclear cannot.

[@3rdeye399]

I feel that one issues with heat pumps that is never mentioned or taken into account is local Temperatures and how they vary across the UK. It is quite obvious that your average outside temperature will effect your efficiency and over a year your costs will be much different to many others. So the question for me is by living in a colder Scotland or any where else can I lose money by converting to Heat Pumps, and if it has to work harder and longer will it need replaced sooner in the future???????

[@mfr58]

Yes, large towns and cities are heat islands, so the HP performance is likely to be better than in rural and northern areas.

[@itsLewis09]

Two thirds of Norwegen homes have heat pumps, I'm sure if it works in Norway there's no issues with the slight cold we get in the UK, even in Scotland....

[@3rdeye399]

@@itsLewis09 yes it may work...I am talking about relative efficiencies and costs over time and can everyone afford them. If the temperature outside is 0 deg C and you want to produce 20 deg internally you have to use Electricity... then you also have to look at the cost of Power but that over time depends on Climate and Carbon restrictions... as we speak there are laws being draughted to restrict your consumptions on all homes, not only that, they are enforcing Home Efficiency ratings to be at certain levels....this will cost tens of thousands and will be incremented over time. Also you are restricting yourself to one source of power and are reliant on an infrastructure that is not fit for purpose...it is failing now with EV's......

[@johnnyhollis9977]

I have a friend who lived in an Edwardian terraced house as do many people. She asked her very experienced heating engineer about heat pumps and he told her it would never ever work in that type of environment. I wonder what the government plan to do about the hundreds of thousands of properties that are in that same position?

[@711yada]

I live Texas and have an air source heat pump. Last winter we had quite low temps for central Texas, -12c, the heat pumps became ice and the "emergency" electric heater kicked on inside the unit. It was pathetic. I kept the bedroom warm with a portable propane heater, but the rest of the house was at 4.5c. This year we have firewood and a fireplace insert w/blower... In addition to the pathetic dual heat pump unit. Maybe I'll knit a couple of square sweaters for them and cozy them up...

[@edc1569]

The problem is in Texas professional engineers couldn't even work out how to keep gas power plants on in freezing conditions, which resulted in those appalling black outs, so expecting a HVAC installer to be more competent in Texas is probably stretching it. Plenty of people in nordic countries heat their homes with heat pumps without any drama.

[@711yada]

@@edc1569 I cannot believe that northern climate use air source heat pumps. As for the power plants. That was and is highly suspect. Gas doesn't freeze, at least not where I'm from, Montana and Colorado.

[@somedude-lc5dy]

you bought a unit that didn't handle cold temps. that's either your fault or the builder's fault. don't blame the technology. lots of units can easily handle -15c easily.

[@711yada]

@@somedude-lc5dy How does an iced up heat pump extract heat from-15?? Explain, I'd like to understand.

[@hk78901]

​@@711yadabecause heat (i.e. energy) is not the same as temperature

[@WindyJAMiller]

Solar gain in the ground comes from the rain as well. Ie warmer rain gives the ground heat.

[@jonjo6886]

I love heat pumps. Gas generated electricity is about negative 2.5 CoP and we use electricity to operate heat pumps at positive 2.5 CoP.

[@jonjo6886]

A couple of days ago, here in UK 70% of our electricity was from gas (58%) and imports (12%). There's no solar to speak of in the winter and no wind on misty days.

[@jonjo6886]

The best answer is, if you have a high heat loss property, insulate/draughtproof and use timed heating for the spaces you actually use. Ask Martin Lewis!

[@antoniodesousa9723]

timely, I had door to door sales kids asking to setup a free consultation for a heat pump here in Canada. Something about a gov rebate. My parents had one in the late 80s, pretty large cylindrical fan unit in the backyard annoying our summer parties. Winter temps get down to -10 celsius and summer up to 30. I have no evidence but i would think insulation, better windows and doors are better investments.

[@Gixer750pilot]

Love a Rogers Rant 😊

[@emmacohen3926]

Absolutely brilliant explanation 👏👏👏🔥🇬🇧🇬🇧

[@Cien_Swiatla]

I like the drawings equipment you have behind you, and the true you show in this video

[@liammullan2197]

Nice one Roger. I've dipped in and out of your videos over the years, I always thought you were dead against heat pumps but I'm glad to see you are embracing them and spreading knowledge.

[@SkillBuilder]

I am not exactly embracing them. I think they have a place. If you are using electricity and have no mains gas they are well worth considering. My whole premise, which I explained right from the start, is the madness of the Boiler Uprgrade Scheme which uses tax payers money to bribe people away from gas. It has caused misery for thousands of people and we get emails every week telling us about the disasters that unfolded when people decided to follow the government advice. If you have a working gas boiler there is no point scrapping it for a heat pump and if your house is not well insulated (you may have solid walls) then a gas boiler is much better. It allows you to put heat into the building quickly at a higher temperature. Using a low temperature heat pump in cold weather is not going to keep pace with the buildings heat losses. I also know they will make no difference to climate change, it is just too insignificant.

[@martinwarner1178]

@@SkillBuilder And climate change is happening, but the gov.com has hijacked this natural occurrence to blame/charge us all......just saying....because...err..covid.

[@FiscalWoofer]

Hi Roger, great video…wonder could you do one on cost of heat pump vs standard gas/oil both in super insulated house. It seems it’s more about insulation than the fuel source?

[@somedude-lc5dy]

depends a lot on your local cost of gas and local cost of electricity. it also depends on zoning. I use mini-splits and I save a lot of energy by simply keeping units turned down or off in rooms I'm not using. boilers and central forced air usually heat every room the same regardless of whether you're using it.

[@maryhaddock9145]

Thinking of a water source heat pump. Can you use a ground source system fof that?

[@richarddixon6354]

Great video, thanks. Living in a 6 year old house, stuffed full of insulation, I can no longer take another summer trying to sleep in a bedroom temp of 33c with the window open. This can happen with only an outside temp of 25/26c so I am looking at an air to air system to heat and cool regardless of what the government think. Why don’t they offer the grant providing you get solar panels at the same time which would power the cooling in the summer. Doesn’t make sense.

[@mfr58]

You would need a big PV array to power the cooling system, most urban houses wouldn't have the space or orientation.

[@billgreen576]

Then get a portable air conditioner for about £300.

[@flashback9966]

Currently 1.2 million heat pumps in Germany. Some of these must work!

[@SkillBuilder]

Maybe they all do but this is not about them not working it is about confusion over terminology

[@miken3963]

Mine sure does. It just has to be designed and installed properly by people who know what they are doing. I've got a ground source heat pump in a properly insulated house that takes about 4 kWh per day to heat the entire house in winter. During hot summer days it takes about 1 kWh per day to cool the entire house. And no, it doesn't freeze the ground in winter. Cause the ground loop was properly sized with the house's heat load in mind.

[@paul756uk2]

Underfloor heating is more common in Germany. Heat pumps are more suited to this method of heating as the temperature required is lower than for radiators which is more common in the UK.

[@pauldavies7251]

​@@miken3963total fitting cost including materials & running cost?

[@newyorker641]

I'm from DE. I've seen some air/water heat pump retrofits in older homes, putting them in costs a fortune. They run on a separarate meter with a ripple relay - old meter panel with no space for a 2nd meter? Get a new one - 2500 to 3000€ just for that. The highest offer for a house from 1991 with two heating circuits (radiators + uf) was 48,000€. On average I would assume roughly 20,000€. In my place electricity at night for heating "Heizstrom" is 34 ct/kWh and at daytime 37 ct/kWh, gas is at 10 ct/kWh. The sometimes very utopian Fraunhofer institute has made a research (have they looked at all?) about ASHP and claim they reach a SCOP of 3,1 which would still be more expensive than gas. What I recommend: split ACs and a DHW-hp and leave the gas boiler, those split units reach easily a COP of more than 4 in spring and autumn and the DHW unit 3.5 in a typical German basement/cellar. Combined with some solar panels this cuts the heating bill by at least 50% and is trouble free and easy to install, radiators are not touched and in february with down to -18°C (Bavaria) nothing struggles. Our madness-government with green fanatics destroyed the property value of older homes with their "Heizgesetz" (heating law) sometimes by more than 50%. ASHP are ideal for new homes with 30 cm insulation around them and uf heating run at 25°C. ASHP are useless in millions of German apartment blocks with "single pipe" heating systems (radiatots connected in series with a bypass) due to operating temps. of 60 to 80°C. As a result the AfD (like the UKIP) is on the rise, in East Germany (they hate commie greens - no wonder after 40 years suffering in the GDR) some polls reach 35%. Try forming a state government there - we need sensible politics, nuclear power and solutions that work for people with average incomes. Robert Habeck (it is his idea), please go home.

[@dinendale666]

There are 2 x kinds of ASAP that use water , mono block which you are talking about and there are split systems that do heat water .

[@stephengolds9679]

Well explained Roger

[@arekarek1991]

Proper insulation done like in other countries ! Only external wall insulation , floors ( water floor heating is most efficient), changing windows for some good quality made (maybe from import Gealan -Veka? ), normal good quality doors.

[@spankeyfish]

GSHP is probably best combined with solar thermal so you use the borehole for interseasonal heat storage.

[@wazza33racer]

Every technology has it limitations. Thanks for that excellent explanation of ground source heating...........most people fail to explain that the ground can be saturated from heat extraction, they assume there is always enough heat in the ground to always provide enough energy.

[@redshift3]

only a problem if badly designed / installed

[@barronfartpants6849]

It's old technology, it's just a vapour compression system its been done for years in one way or another . It's just new in people's houses , retail units have had co2 pack systems with heat exchangers for years so they can run their refrigeration and heating of one pack . The trouble with the vapour compression system is it breaks down all the time . The old gas boiler is way more reliable in all honesty but it's a money maker

[@SD-eu7ht]

I beg to differ Heat pumps with a vertical well produce heat by extracting thermal energy from the ground and transferring it to a building's heating system. The ground, even at relatively shallow depths, maintains a relatively constant temperature throughout the year, making it a reliable source of heat. Here's how it works: Heat Transfer Fluid: A fluid, such as water or a refrigerant, is circulated through a closed loop of pipes buried in the vertical well. Heat Absorption: The fluid absorbs heat from the surrounding ground, which is typically warmer than the air during winter. Heat Pump Cycle: The heat-absorbing fluid then enters the heat pump, where it undergoes a thermodynamic cycle that concentrates the heat. Heat Release: The concentrated heat is transferred from the heat pump to a heat exchanger, which warms the air or water that circulates through the building's heating system. Cycle Completion: The cooled fluid is then recirculated through the vertical well to absorb more heat, and the cycle repeats. Vertical wells are particularly efficient for heat pumps because they provide a large surface area for heat transfer with the ground. This allows the heat pump to extract more heat with less energy input compared to horizontal loops, which have a smaller surface area. In summary, heat pumps with a vertical well utilize the constant temperature of the ground to extract heat and transfer it to a building's heating system, providing a sustainable and efficient way to generate warmth. So in a closed circuit with a well 45mt deep the average temperature is 12 degrees Celsius. The chances of freezing the surrounding area making the heat pump useless are the same as being hit by a meteor while driving a scooter down a slope in Nepal

[@MyMy-tv7fd]

the quiet killer comment from that Welsh guy telling you about his awful experience was 'it increased our electricity bill by two-and-a-half times'

[@odetterollinson-davies4543]

Yep there’s always comments like that however the truth is somewhat different

[@MyMy-tv7fd]

what, it was three-and-a-half? He was pulling his punches? @@odetterollinson-davies4543

[@SkillBuilder]

What heat pump do you have? You seem to know so much more than somebody who owns one.

[@aster7693]

One thing the pro heat pump zealots say to high electricity bills is “you should have installed solar panels and batteries”….well that’s a mute point as the only comparison to that with conventional boilers would be to have your own oil well/gas reserve to tap into to supplement the grid supply!

[@johnhaydon4055]

How much did the gas bill go down by?? and two and a half times what??

[@engineer17151]

For air source heat pumps to work effectively in UK (given their present COP) the property concerned needs to be insulated to the highest degree ... simply because the high discharge side of the refrigeration circuit which heats the water circuit heat exchanger will predominently offer only around 50-55 degrees C. And in most older UK homes is not suffice to give comfort levels of 19-21 degrees C internal temperature, because of fabric heat loss ... especially in prolonged winter periods of around 2 degrees to -5 degrees C. That is why often they recommend changing all the radiators to try and compensate for the fabric heat loss that is present. A lot of people find they are using copious amounts of energy (kw/hrs) but not getting the comfort levels required. In UK at the moment in those circumstances they are hardly viable. And yes, I worked in building services and am refrigeration trained.

[@stephenskinner3851]

And half the year UK experiences cold to coldish weather, including periods below freezing, and the other half warm to warmish, including periods of heatwaves. I have experienced at least 1 heatwave a year, every year of my life and that means not being able to sleep properly - every year. Therefore, insulating against heat loss solves only half the challenges.

[@littlewing2856]

Hi Roger! Please help. We are renovating a big neglected damp house in the far north Highlands of Scotland which is 100+ year old solid wall house. It has 4 bedrooms upstairs and an old shop downstairs. We have no decent insulation at present - just the air gap behind the drywall. We have no gas provision and no heating system except plug in electric heaters. I am contemplating accepting the free insulation and heat pump, but i've been told that it doesn't work for solid wall houses; only very well insulated houses. Do you think that if we accepted the internal insulation to 2/3 of the home there is a chance that the heat pump would be worthwhile accepting? On the one hand I think they might be a con; on the other hand we're desperate for an affordable way to get our house warm. (My electricity bill for the last 2 years is over £5000) . Thank you 🙏

[@griffithsheating]

I recon Rogers wife ran off with a heatpump installer

[@mikerodent3164]

😂... Or maybe she ran off... but **she** was a heatpump installer.

[@johnmcmullan9741]

Heat pumps are mature technology in some countries, including the coldest in northern Europe. Do the physics. They work very well.

[@davebutler3905]

Well done. That makes a lot of sense!

[@wigss3606]

Hello from Ireland, my niece has an air to water heat pump, why is her electric so high?

[@TurinTuramber]

Emersion heater doing all the work?

[@wigss3606]

thanks, ill check with her, that could be it, @@TurinTuramber

[@wigss3606]

yes her emersion is on all the time, and she has a timer for the rads to come on, she was told it was cheaper to have it on all the time because when she needs it it takes more electric to heat it back up again, can she heat the rads if she turns off the emersion?@@TurinTuramber

[@edc1569]

rates have gone up mate.

[@nigelpendall4809]

A lot of people make the mistake of thinking that a heat pump is just like an old style gas boiler. They try to use it in the same way and come unstuck. They are NOT the same and to get the best out of them they have to be used differently. A key factor is flow temperature. Gas boilers will happily produce water at 70c but heat pumps struggle past 45c. Keep the flow temperature low and a heat pump can be great and cheaper to run than gas. People think radiators have to be HOT. wrong, they just have to be warm enough. My heat pump is currently running and producing water at 29c. The house is at 19c. Run long and slow. I run my system 24/7.

[@GlennPowell-ls3lg]

In very simple turns if you ever feel pipes on the back of your fridge or freezer they are warm due to the heat exchanger principle.However I cant get my head around heating a whole house with heat extracted that way without using alot of sparks to drive a big exchanger and I certainly cant see how it can heat water up more than a few degrees.

[@garethjudd5840]

A realworld homeowner review who owns a heat pump would be interesting in regards yearly performance and costs etc.

[@SkillBuilder]

you mean like this guy kzbin.info/www/bejne/kJLVaIWKhtSXpNk

[@Lewis_Standing]

Or alternatively excellent performance of heat pumps in uninsulated houses! Roger says it can't be done. Is he wrong? kzbin.info/aero/PLDiAM6PgxBWSHvNXvvofPzxJ7pQ5ZJvd2&si=SZ4w3trZiDN-_n_9

[@somedude-lc5dy]

it depends very heavily on the price of gas, and price of electricity.

[@terryh8421]

Mini splits for me!

[@seanduffy2214]

We have a couple of air to air systems. They are insanely efficient in both heating and cooling. I've got a plug that tracks the power consumption and our peak month is 24kwh usage. And thats when we have it on for 10 hours overnight everynight. Also you can control them room by room unlike central heating. Im seriously considering getting a couple more for the rest of the house. A couple more points. The main reason you don't get a grant is not the cooling element but they don't do hot water like air to water heat pumps. And so many people get confused by the rating of them. A 6kw heat pump doesn't consume 6kw of electric, thats the max heat output. Ours seem to run at 200w even when on full blast.

[@keithoneill6273]

I agree. I'm in the UK and have had a single outlet Midea air-to-air HP for 3 years now. It's been a great success. I disagree with Dave about the cooling aspect. With our UK climate, I've only used mine for cooling a couple of times, so I'd argue that doesn't negate the benefits. Also it was very cheap by comparison with air-to-water, even with no grant.

[@chrisreed3929]

I would love to hear the government explain how in this world an air source heat pump will manage to effectively warm my 170 year old solid wall house using the current radiators. Yes they will talk about external wall insulation, floor insulation and retrofit low profile underfloor heating. Only problem, I haven't got £30k+, and that is a fairly accurate costing.

[@jellevp]

In Belgium it's allowed to cool with a heat pump in the summer if you have solar panels installed. But it's only since last year...

[@examplerkey]

How can you extract heat from colder air outside?

[@drummerdem50]

Great insight Rodger , so differeent from the US

[@iansymington8493]

Thanks Roger another great video. So I worked out the following: Based of fuels and 8 euro cost of fuel as base line to output kwh. 6mm Pellets with approx 5 kwh per 1kg 15 kg bag 8.00 euro x 15kg = 75 kwh output Coal with approx 8 kwh per 1 kg stove used (40kg bag 24 euro) 8.00 euro x 13kg = 104 kwh output Kerosene approx 10kwh per 1 L. 1L = 1.35 euro. 8 euro 6 L fuel = 60Kwh output. Can 3x this by mixing in burnt oil (free) after filter mix etc 180Kwh (Chinese heater) Mitsubishi heat pump Air to water 3.2 COP to 4.8 COP (2016) 1 kwh at 0.31c. 8 euro = 25 kw COP3 = 75kwh output. As we can work out the calorific value for fuels... or at least approx due to efficiencies of stove, pellet burner and fuel heater... How do I confirm the COP output of the Heat Pump? Had a look on line to see if could buy a plug in play device. Electric used, measure of water heat out and in including flow speed? I would think thats whats needed. If I had a COP 1, how would I know as without the COP value confirmed its really the most expensive here to run maybe... Its the not knowing. Another video coming....

[@RosyOutlook2]

Inefficient in cold weather

[@pinarellolimoncello]

Whip'em into shape Roger, that is what I like to see. Very clear and concise video, well done. Quote them proverbs...'He that loveth his son, spare'th him NOT THE ROD!', have to say it in a voice like Brian Blessed though.

[@SkillBuilder]

Brian Blessed, now he was loud.

[@jasonantigua6825]

Thanks Richard,I’m absolutely none the wiser after all that!!!

[@tomaskmonicek5521]

We had a Daikin mini split air conditioner installed in our 1930s 3-bedroom house. 5 indoor units connected to a 9kW outdoor unit. The house is about average in terms of insulation for UK standards (cavity wall, loft, double glazing). The house had storage heaters when we bought it, so it was either a full central heating install or this. The system cost us £9k for top of the range model, central heating would have been £8k. We used about 80kWh of electricity a month (approx. £21) in July to cool and 300kWh of electricity this November to heat (approx. £81). We can monitor our energy usage down to 2-hour intervals for each room in the app. We still use a small,on-demand gas water heater for hot water. The system works great, each room can be controlled individually on our phones, rooms heat up in a matter of 10 minutes, and having cooling in the summer is next to none in terms of comfort. Having the extra wall space is a bonus too. The only drawback is that the indoor units do make a bit of noise as they are fan-assisted, but they quickly blend into the background. It's a shame the government doesn't support air-to-air systems with grants, as our CO2 impact is still measurably lower than a gas boiler, and most definitely much lower than a poorly installed air-to-water system. It would be good to see more info on air-to-air out there as it seems, right now, the overpriced monobloc heat pumps are all people know about.

[@frederickbowdler8169]

Tip for heat pumps paint backing wall matt black this absorbs solar heat and in turn heats the air which is then extracted by the pump.😊😊😊🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉

[@TurinTuramber]

I would install a log burner before I installed an ASHP.

[@mikerodent3164]

Log burners are illegal in the whole of Greater London and, I think, in most cities in the UK. It's not just because they generate CO2, but also vast quantities of particulates. Millions of our ancestors will probably have died much younger than they might have because burning wood or coal was their only option at the time.

[@TurinTuramber]

@@mikerodent3164 1) I don't live in any of those rat nests. 2) They only realise the CO2 that was captured during growth of the tree. Just the carbon cycle in action. Different to burning dug up fossil fuels in your boiler. 3) Houses are full of dust and stale air. If I wanted to live forever I would avoid refined sugars. Diabetes, hypertension and suicide kill people now. 4) Don't pity our ancestors, take a look at how people live now. They would pity our existence.

[@ian4iPad2]

Had a log burner in an old cottage during the 90s. Did the job. Leaving all the inside doors open, it warmed the whole house. Very cheap to install at the time, cheap to run especially if you had a ready supply of wood. Mentally calming too, probably watched the flickering flames as much as the telly; lovely smell too with particular types of wood. It was a rural location though, probably not good for those in dense areas of population.

[@megapangolin1093]

Frozen ground kills earthworms and other beneficial organisms. Very "save the planet". Great video Roger, very simple and straightforward to understand.

[@philiphumphrey1548]

In the UK there is no spare low carbon electricity. It's usually less than 50% of existing demand for electricity. It won't be 100% for the foreseeable future. Therefore any new heat pump will be running on gas burnt in a power station. It takes about 3 kilowatt hours worth of gas to generate 1 kilowatt hour of electricity. So for every kilowatt hour your heat pump uses it has to retrieve 3 kilowatt hours worth of heat just to generate the same CO2 as a gas boiler. It will also take that ratio to roughly break even on energy cost, since electricity is at least 3 times more expensive than gas. Add in the extra cost of the heat pump and installation and remembering that it, like a gas boiler has a life and will have to be periodically replaced, and you can quickly see it's more expensive.

[@BenIsInSweden]

Where's your data on taking 3kWh of gas to generate 1kWh of electricity.? Anywhere I've looked said that gas power plants in the UK are just shy of 50% efficiency, so just over 2kWh of gas. With Keadby 2 being over 60% efficient, so requires ~1.7kWh of gas. Even if you account for grid losses, it's still not getting close to 3kWh of gas required. Also in a gas boiler, you don't get 1kWh of usable heat from 1kWh of gas. It's around 0.8-0.9kWh of heat per kWh of gas.

[@BenIsInSweden]

It may be the difference in terminology, but over here, ground source = horizontal loop, geothermal (or "rock source") = vertical loop. The UK seems to use Ground Source to describe both horizontal and vertical loops. Either way, freezing of the borehole generally isn't an issue - in fact, it can be a benefit, as the phase change releases extra energy. If it gets cold enough to the point where it is insufficient for the heating demand, then it simply - like a lot of heat pumps in the UK - hasn't been sized properly. The loops also don't just rely on the sun to get re-heated. Passive cooling over here means that in Summer the loop is still running (but not the compressor), and it will steal some heat energy from the house to add back to the loop. Active cooling - when you have a cooling circuit, will run the compressor and act like AC - cooling the home, but heating the loop. Recently things have come on the market for PV-T to use the loop as a thermal store - so you can use the summer months to put heat into the loop, storing it for heating in winter. Basically, troublesome freezing should be a thing of the past going forward. Also whilst monoblocs are the most common design in the UK, split air-to-water systems are also being installed - typically the Daikin high-temperature ones. The monoblock has 2 advantages - 1) can use R290 refrigerant (better efficiency, and lower GWP), and 2) doesn't need the installer to be F-Gas.