For real. Everytime I get in the shower I end up having to point the showerhead away and cower from the cold water and I could have just turned it on first?

        • DosDude
          link
          fedilink
          141 day ago

          It’s just dumb engineering to heat up a pipe the entire day for the 0.8% of the day you need it to be hot.

          • @Honytawk@feddit.nl
            link
            fedilink
            26 hours ago

            Heat pumps generally use a lot less power. Don’t need to heat up much if it is already slightly hot.

          • FackCurs
            link
            fedilink
            112 hours ago

            It’s typically used for large complexes like campuses where the hot water is made en masse in one building and the loop goes around all the other buildings. Helps keep cost down (at construction) because you only need one giant water heater. Helps not have to wait 10 minutes to bring the hot water to your building. Energy still gets wasted but given the number of users, not that bad.

          • snooggums
            link
            fedilink
            English
            231 day ago

            Insulation + retaining heat means it isn’t nearly as energy inefficient as you think.

            They keep the water tanks heated all day, and not heating the pipes means they have to do more work as they are drained of more water to fill the length of pipe to the shower which will then lose that heat over the course the day, only to need the water heater to heat it back up again.

          • @aubeynarf@lemmynsfw.com
            link
            fedilink
            4
            edit-2
            24 hours ago

            You don’t have to heat it up all day. Did you just post the first “anti” thought you had without giving one minute of consideration to how modern controls work?

            • DosDude
              link
              fedilink
              124 hours ago

              Have you read the previous comments? Because that’s exactly what’s implied.

      • @papalonian@lemmy.world
        link
        fedilink
        341 day ago

        Someone else already pointed out that these are usually pretty well insulated systems that don’t radiate much energy, but also consider how many dozens of gallons of water aren’t being wasted by waiting for it to be warm.

        • @BossDj@lemm.ee
          link
          fedilink
          9
          edit-2
          24 hours ago

          Nearly all of these systems are put on timers. So they stop cycling while you’re at work or over night. They’ll often make it a part of the smart home ecosystem as well, so you can override from a smart home device or phone

      • dohpaz42
        link
        fedilink
        English
        181 day ago

        If you have a hot water tank, that hot water is just sitting there getting cold just waiting to be heated up again. A circulating pump puts that hot water to use by circulating it through the pipes, which has a nice side effect in cold climates of preventing the pipes from freezing and bursting. I doubt it wastes much energy as you think.

        • @aubeynarf@lemmynsfw.com
          link
          fedilink
          424 hours ago

          Hot water tanks do not just “get cold”; they are fantastically well insulated. And a great way to lower peak energy usage by accumulating heating power, making it possible to use a heat pump to heat the water.

          • @BastingChemina@slrpnk.net
            link
            fedilink
            321 hours ago

            Hot water tanks are usually not that well insulated. If you want to save electricity an easy thing to wrap a good later insulation around it.