• ArbitraryValue@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    0
    ·
    edit-2
    5 days ago

    What can “never” mean here?

    For coal, however, if you invest 1kWh you typically get below 0.4 kWh in return.

    So people run coal plants to destroy energy? Like, you have too much electricity and so you build a coal plant to get rid of it?

    I’m not sure that whatever metric this source uses matches what most people think when they hear “energy amortization”.

    • JohnDClay@sh.itjust.works
      link
      fedilink
      arrow-up
      0
      ·
      5 days ago

      Since the emissions in the lifecycle of a wind turbine are from the energy used, the time period lasted would also be when it breaks even on CO2 emissions.

      As for destroying energy, that’s just the efficiency, the other 60% is wasted as heat.

    • driving_crooner@lemmy.eco.br
      link
      fedilink
      arrow-up
      0
      ·
      5 days ago

      So people run coal plants to destroy energy?

      The energy was in a state that was not useful, and to generate useful energy with it you need to keep the input of that energy source flowing.

    • jdnewmil@lemmy.ca
      link
      fedilink
      arrow-up
      0
      ·
      5 days ago

      If you convert the chemical energy in a unit of coal to heat (burn it) you can calculate how much energy exists in that coal, measured in appropriate units (e.g. kWh). That is evidently what this author is trying to dumb down as “invested energy”. The amount of energy extracted as electricity is typically 40% of that… the rest ends up as heat which is much less useful than electricity.

      I agree that this is not particularly useful in discussing the merits of different energy sources because good design tends to do as well as is practical and the supply of fuel and negative impacts of that process can’t vary dramatically.