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Heat pumps

Discussion in 'Home and Garden' started by Uther, 19 Oct 2021.

  1. Yaayuh!


    Joined: 5 Nov 2010

    Posts: 21,863

    It's really not as simple as that. To insulate our house we would have to get the rooves rebuilt, whilst it is possible, it will cost a tremendous amount inc planning. Those in listed buildings it will be even harder or even impossible.
  2. bobuk


    Joined: 25 Jan 2009

    Posts: 486

    over 15k quote, don't think I will bother for a while, wait and see if prices come down.


    Joined: 3 May 2012

    Posts: 4,099

    I was thinking about this or even a mechanical battery I'm not sure how feasible?

    They need to do it more I think, there is a place called power mountain in Wales near Snowdon but im sure there are more, there is basically a lake at the top of the mountain, which is effectively a giant mechanical battery.

    Water is pumped up when energy needs to be stored and when released it flows was back down again generating energy back.

    Not sure if this could be done on a smaller scale may be using weights? Batteries have limited lifespans and use precocious metal.
  4. Journey


    Joined: 18 Oct 2002

    Posts: 10,356

    Location: West Midlands

    Heat pump is the last part of the upgrade for us, now that we have solar, home battery storage and an BEV already. Total removal of gas is the goal, and be as sustainable as possible, will likely need to add another battery if V2H or V2G doesn't happen as soon as I'd like.

    Cost is secondary right now, as we decided that we wanted to remove the fossil fuels we consume where we can.
  5. PlacidCasual


    Joined: 13 May 2003

    Posts: 7,469

    Batteries don't address the issue of cost.

    Electric heating, hot water, cooking and transport could conceivably increase electricity demand by 100% Making that energy cheap enough that people can afford to do those things is not going to be an easy task. Insulation is a major issue for the UK because of our old house stock. Smashing down 20+ million homes to put up modern pokey homes is not a solution. We need a cheap energy policy and if that involves large scale nuclear roll out then all the better.
  6. lookitsjonno


    Joined: 10 Sep 2003

    Posts: 4,487

    Location: Midlands

    From what I can tell it was mostly means tested so lots of the population were excluded, or required to pay towards it
  7. alec

    Wise Guy

    Joined: 11 Dec 2016

    Posts: 1,407

    Location: Oxford

    Read two BBC articles on the topic in past couple weeks. Both were pushing a stat to convince that "gas boilers are bad, mkay, go heat pumps"

    One said gas boiler emissions in UK equal all of lorry emissions (and then in fine print below elaborated that it was only for NOx)
    Other said 21% of UK carbon emission comes from heating homes. Didn't say was it only from gas fired boilers used for heating homes.

    Very suspicious tactic to scare people into this.

    To me it is obvious that it is more efficient to
    burn gas - heat water
    at home rather than go into long chain of
    burn gas at station - run turbine - generate electricity - transmit over power lines - run heat pump with electricity - heat water
    And if it isn't heat pump, immersion heater is even more inefficient
  8. lookitsjonno


    Joined: 10 Sep 2003

    Posts: 4,487

    Location: Midlands

    Financially so, but in terms of emissions perhaps not? Electricity generated on grid is significantly more greener than burning gas at home...
  9. 200sols


    Joined: 14 Jan 2018

    Posts: 9,142

    Location: Hampshire

  10. b0rn2sk8


    Joined: 9 Mar 2003

    Posts: 9,259

    You are completely missing that heat pumps have a coefficient of performance of around 350% (based on the quote I had averaged across the year, peek performance was well over 400%). So for every kWh of electric you put in, you get on average 3.5kw of heat.

    With boilers are best you get is 90% if they are correctly set up which most are not.

    So no boilers are not more efficient at all, cheaper yes but far worse on emissions which is the point. Even if you powered all the heat pumps with gas fired power stations, emissions would be cut by two thirds. That obviously comes at a cost.
  11. lookitsjonno


    Joined: 10 Sep 2003

    Posts: 4,487

    Location: Midlands

    I've seen a few articles like this, but they don't say what type of gas boiler they the numbers are based on. It reads to me like they are labelling all boilers as "bad". I think it'd be an easier sell getting those with 20+ year old boilers to upgrade to something modern and A-rated for significantly less than £5000. What would be the numbers then?
  12. b0rn2sk8


    Joined: 9 Mar 2003

    Posts: 9,259

    It’s irrelevant, a heat pump powered by gas fired power stations puts out 2/3 the emissions of the best A+ rated boilers and has the potential to put out zero emissions when powered by renewables. That’s the end game.

    All forcing everyone to get a A rated boiler does is kick the can down the road a few years at best. It’s also 2035 so the cut off is over a decade away.
  13. Abraxaz1

    Wise Guy

    Joined: 7 Jun 2009

    Posts: 2,470

    Location: Carmarthenshire

    Heat pumps are next to useless in old houses. Unless you have underfloor heating then you will be worse off than with what is already installed.

    Heat pumps only go up to a maximum of 45 ish degrees, due to the pressure factors in place, to get warmer the whole thing would need to be made out of stainless steel.

    That combined with the fact they have multiple issues in cold weather. The air source units actually turn them selves off if the ambient temperature drops too low as the decompression expansion vessel cannot be warmed up enough.

    The ground source ones either require bore holes in low surface soil areas or large trenches, so you need a big garden. If the temperature gets too cold in the building and you turn it up too much you can end up freezing the ground around the heat exchanger.

    Plus you'll need a emersion heater for hot water, as I doubt people will want to do washing up or showers in Luke warm water...

    Things are going to get very expensive for people when they start to decommission the gas network.
  14. pinkpound

    Wise Guy

    Joined: 31 May 2005

    Posts: 2,278

    I'm just grabbing my popcorn ready for this to hit the poop fan in years too come.

    10-15 years from now "Sold a heat pump system and it was **** blah blah lawyers will help you with your claim for compo "
  15. kinetic747


    Joined: 2 Apr 2006

    Posts: 2,894

    Yes, you had to be in receipt of benefits to get the grant I think. EDF were doing cavity wall insulation free a few years ago but when I applied I couldn't get it as the old stuff had to be removed first. I'm going to revisit this at some stage as it still needs doing.
  16. Fubsy


    Joined: 12 Dec 2003

    Posts: 9,825

    Location: Berkshire

    I hated the idea of moving into a place off the gas grid, but looking at all the alternatives to the oil burner/boiler/tank combo we had, the cheapest and most effective was still oil. Heat pump would have been very expensive and crap during the depths of winter (same with ground source), and fully electric was cheap but horrendous running costs unless we spent many times more on battery storage for the pitiful amount of solar generation in the winter.

    We need more nuclear, and we need it yesterday.

    How are the Germans doing it?
  17. The_One


    Joined: 27 Dec 2003

    Posts: 12,962

    Current gas engineer my employer currently do fit air source heat pumps

    Most homes that get quoted cant have them theres a big issue in siting the unit outside due to clearances you have to have around the unit form other properties and structures/buildings etc. A lot of semi detached properties will struggle and terraced houses you can forget about it

    Also have to oversize all the rads which most customers when they get told say nah no thanks cant lose any more space in my rooms

    Hydrogen is the only way to make it work in the home, theres currently a trial taking place up scotland but its for boilers that run on a gas/hydrogen mix (80% gas 20% hydrogen)

    Big issues with fully hydrogen homes due to how volatile and explosive hydrogen is
  18. Jokester


    Joined: 7 Aug 2003

    Posts: 42,456

    Location: Aberdeenshire

    I’m pretty sure we’ll end up using the existing gas network for bio-gas/renewable generated synthetic gas/hydrogen blend. Makes almost all the end user issues go away.
  19. Macky


    Joined: 5 Apr 2009

    Posts: 5,850

    Location: England

    Was thinking similar about the positioning of the units. We have a semi with a conservatory with bi-folds at the back and a bay window at the front. And there's no chance it would fit down the side alley! So nowhere to put a unit!
  20. 413x


    Joined: 13 Jan 2010

    Posts: 23,500

    Location: Llaneirwg

    It's the added cost. New rads all round?
    Retro fitting. Need solar to actually be cheaper.

    It's great it's greener but probably a long way off for me. Even though boiler is 20 years old it works well.

    Doubling rad size would be very annoying the house isn't that big so it would be a noticeable loss of space. Do you actually have to double rad area?

    The space for the outdoor part of the pump would be fine