• SomeoneSomewhere@lemmy.nz
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    6 days ago

    In moderate climates it is more efficient to burn gas to produce electricity then use that to run a heat pump, than it is to burn gas directly.

    Gas power plants are about 35-60% efficient depending on whether they’re a cheap inefficient peaker or Rankine, or a pricey CCGT plant.

    Heat pumps have a COP of 2.5x to >5 depending on outdoor temperature and series.

    Good gas furnaces/boilers and the grid are both upwards of 90% efficient.

    So a 40% efficient gas plant driving a COP 3 heat pump produces 1.2x the heat that you get from burning the gas directly. That’s close to worst case and you can also run your grid on other fuels.

    • Tar_Alcaran@sh.itjust.works
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      6 days ago

      Heat pumps also have the benefit they can run on solar power.

      There are plenty of days when it’s still sunny, but not very warm, and my heat pump runs “for free” most of the day.

    • HaraldvonBlauzahn@feddit.org
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      6 days ago

      Also, you need to burn gas only when there is no wind blowing in the winter. Which does not happen that often around the North Sea. Adding modern batteries, gas might be needed 2% or 3% of the time. Which means 97% of CO2 eliminated cheaply, and fast.

      Though, adding wave power to complement wind would be nice, since the sea surface then provides free energy storage and energy transport to the shores, and waves in North Sea winter get easily 6 meters high.

      They even had to invent some crazy engineering to access wind power plants in typical winter weather - see “Ampelmann Gangway” at YouTube…

      • SomeoneSomewhere@lemmy.nz
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        5 days ago

        With wind, at least all the moving parts tend to be well above water, only exposed to salt spray (though that’s still pretty nasty).

        Tidal and especially wave have moving components exposed to water, often right on the wind-water line. That makes them corrosion and maintenance horrors.

        There have been plenty of demonstration wave & tidal plants that have produced power, but I think the operation record is about two years, most much less.

        Building and scrapping your plants every year or two is neither cost nor energy efficient.

        Solar, hydro, geothermal, and wind are much nicer to deal with.

        • HaraldvonBlauzahn@feddit.org
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          5 days ago

          Tidal and especially wave have moving components exposed to water, often right on the wind-water line. That makes them corrosion and maintenance horrors.

          True, the environment is not easy, and a lot of detail problems need to be solved.

          But ships solved the same issues.

          The charm of wave power is that the ocean surface is the storage medium. The surface stores and transports the energy to the shore.

          This is a very powerful principle.

          • SomeoneSomewhere@lemmy.nz
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            5 days ago

            Ships haven’t really ‘solved’ the same issues. They’re dry-docked at regular intervals (about every 5 years?), have minimal moving components below the waterline, and get the props cleaned by divers more frequently.

            They are also capable of travelling to dry-dock under their own power and deliver a lot more revenue than your average wave turbine would, so the costs of dry-docking them aren’t as significant.

    • saimen@feddit.org
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      6 days ago

      Electricity can relatively easy be generated almost infinitely. We will run out of gas sooner or later.

      • SomeoneSomewhere@lemmy.nz
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        5 days ago

        Absolutely. The point is that even when people say “ha ha, your [heat pump | EV] still actually runs on gas/oil/coal to make its power” - you’re still using less gas/oil/coal than you would with conventional gear, even if the power grid was 100% gas/oil/coal. Which it’s not.

    • decolo@piefed.social
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      6 days ago

      The point is to remove gas dependencies one at a time, so the impending forced transition is as painless as possible.

      • SomeoneSomewhere@lemmy.nz
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        5 days ago

        Absolutely. The point is that even when people say “ha ha, your [heat pump | EV] still actually runs on gas/oil/coal to make its power” - you’re still using less gas/oil/coal than you would with conventional gear, even if the power grid was 100% gas/oil/coal. Which it’s not.