£9bn due to not having built more cheap onshore wind, £5bn due to poorly insulated homes, £5bn due to low solar deployment, £3bn because new homes were built less efficient.

  • Docus@lemmy.world
    link
    fedilink
    English
    arrow-up
    4
    arrow-down
    1
    ·
    5 months ago

    Heat pumps are great when the house is designed for it. Average uk house with shitty insulation and radiators that are unable to heat the room unless the water is really hot - it’s not going to work well.

    • alibloke
      link
      fedilink
      English
      arrow-up
      5
      ·
      5 months ago

      Not true. Heat pumps just need to be sized correctly

      • Docus@lemmy.world
        link
        fedilink
        English
        arrow-up
        3
        ·
        edit-2
        5 months ago

        Link me to a heat pump that produces water for central heating at 70C or more. Typically, flow temperature is closer 40C, which won’t heat the average house unless you increase (possibly double) the size and/or number of radiators. Which is expensive and not always feasible. You can run heat pumps at higher flow temperatures, but that reduces their efficiency. Don’t get me wrong, i think they are great. But successfully retrofitting to old UK housing stock needs expertise that is in short supply.

        • alibloke
          link
          fedilink
          English
          arrow-up
          2
          ·
          5 months ago

          Houses that can’t be further insulated simply need a bigger pump and larger radiators to make it work. No need for 70 degree flow temps at all, though 50 is easily achievable. With the government grant Octopus are currently charging not much more than a gas install.

          • Docus@lemmy.world
            link
            fedilink
            English
            arrow-up
            1
            ·
            5 months ago

            I’m not saying it can’t be done. But a larger heat pump and replacing all radiators drives up the cost, there is not always space for a bigger radiator, (and water tank), and while higher flow temperatures are possible, it tend to reduce efficiency. Sometimes it’s just not worth the investment, not helped by the big gap between gas and electricity prices in the UK

            • alibloke
              link
              fedilink
              English
              arrow-up
              1
              ·
              5 months ago

              Your initial comment was that the average UK house isn’t suitable for heat pumps. This is incorrect, in the vast majority of UK homes (including the poorly insulated) they can be heated sufficiently by a heat pump.

              Don’t spread misinformation. Some installers have fixed prices regardless of the number and size of radiators. There’s even solutions out there where a hot water tank can be fitted into a standard kitchen cupboard.

              You keep mentioning high temperature units which are less efficient, they are only needed in very niche installs or used by poorly trained installers.

    • Wanderer@lemm.ee
      link
      fedilink
      English
      arrow-up
      4
      ·
      5 months ago

      I don’t see how and air to air heat pump wouldn’t work.

      Insulation needs to be solved yes. But if you heating your house with gas verse electricity if the output is the same then the result is the same.

      • Docus@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        arrow-down
        2
        ·
        5 months ago

        Something to do with physics. It’s not just about the heat output from a gas boiler vs heat pump. It’s the output from the radiator to the room that matters. For the same output, a gas boiler heats the water to a higher temperature than a heat pump. Which means a radiator gives out more heat to the room. As an extreme example, if it is freezing outside and the heat pump produces a lot of water at 15c, it may have a high thermal output but still wont keep your room warm. If it produces water at 30c, the radiator will transfer some heat to the room, but unless the radiator is very big or the room is well insulated, probably not enough.