"This giant bubble on the island of Sardinia holds 2,000 tonnes of carbon dioxide. But the gas wasn’t captured from factory emissions, nor was it pulled from the air. It came from a gas supplier… “The facility compresses and expands CO2 daily in its closed system, turning a turbine that generates 200 megawatt-hours of electricity, or 20 MW over 10 hours.”

    • it_depends_man@lemmy.world
      link
      fedilink
      English
      arrow-up
      25
      ·
      12 days ago

      Could be very high, even the waste heat from the compression could be used to achieve more compression and turbines get to above 90%, that all depends on the scales they’re building this at. 70% overall doesn’t seem unrealistic as an educated guess.

    • kalkulat@lemmy.worldOP
      link
      fedilink
      English
      arrow-up
      2
      ·
      10 days ago

      Damned good question, and I played stump-the-search-engine for 15 minutes and it’s like they’re AVOIDING that question