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Iceland exports carbon free electricity in the form of aluminum.

Reason077 2y ago
It's not carbon free. Iceland's geothermal fields have carbon emissions because gasses trapped beneath the surface are released along with the steam when they're extracted. It's still low-carbon compared to a natural gas power plant, of course, but not compared to wind/hydro/nuclear. And aluminium production is certainly not carbon free: the smelting process reduces aluminium oxide to aluminium metal using carbon electrodes, producing around 14 tonnes of CO2 per tonne of aluminium.
- SoftTalker 2y ago
  Depends on the source of that carbon
- Panzer04 2y ago
  The point is that smelting the aluminium takes tons of electricity, so doing it in Iceland where that's produced via geothermal is effectively exporting that electricity.
  - hinkley 2y ago
    And it’s a relatively light material. So if you’ve got some place where the carbon footprint of collecting and transporting bauxite is relatively low, you can use excess power to smelt more aluminum. The problem with opportunistic loads like wind and solar is whether you can afford to strand expensive factories full of equipment for hours or days at a time while the power availability is compromised. At least with geo this is a smaller problem.
  - jabl 2y ago
    It's actually the reducing of the alumina (aluminum oxide) to metallic aluminum that takes huge amounts of electricity. And as mentioned, that is done with carbon electrodes which are consumed in the process, leading to relatively high CO2 emissions. Though yes, if that electricity would be produced by burning fossil fuels the emissions would be even higher. So it's not like there aren't big benefits to doing aluminum refining in Iceland, or other places with low-emission electricity. There is some R&D work going on though to do this reduction step without CO2 emissions using other electrode materials, see e.g ELYSIS.
    - Reason077 2y ago
      > "It's actually the reducing of the alumina (aluminum oxide) to metallic aluminum that takes huge amounts of electricity." AKA: "Smelting"
- thinkcontext 2y ago
  Good point about releasing co2 from the reservoir, thanks for the correction. I did not maintain that the aluminum was carbon free.

It's not carbon free. Iceland's geothermal fields have carbon emissions because gasses trapped beneath the surface are released along with the steam when they're extracted. It's still low-carbon compared to a natural gas power plant, of course, but not compared to wind/hydro/nuclear. And aluminium production is certainly not carbon free: the smelting process reduces aluminium oxide to aluminium metal using carbon electrodes, producing around 14 tonnes of CO2 per tonne of aluminium.

SoftTalker 2y ago
Depends on the source of that carbon
Panzer04 2y ago
The point is that smelting the aluminium takes tons of electricity, so doing it in Iceland where that's produced via geothermal is effectively exporting that electricity.
- hinkley 2y ago
  And it’s a relatively light material. So if you’ve got some place where the carbon footprint of collecting and transporting bauxite is relatively low, you can use excess power to smelt more aluminum. The problem with opportunistic loads like wind and solar is whether you can afford to strand expensive factories full of equipment for hours or days at a time while the power availability is compromised. At least with geo this is a smaller problem.
- jabl 2y ago
  It's actually the reducing of the alumina (aluminum oxide) to metallic aluminum that takes huge amounts of electricity. And as mentioned, that is done with carbon electrodes which are consumed in the process, leading to relatively high CO2 emissions. Though yes, if that electricity would be produced by burning fossil fuels the emissions would be even higher. So it's not like there aren't big benefits to doing aluminum refining in Iceland, or other places with low-emission electricity. There is some R&D work going on though to do this reduction step without CO2 emissions using other electrode materials, see e.g ELYSIS.
  - Reason077 2y ago
    > "It's actually the reducing of the alumina (aluminum oxide) to metallic aluminum that takes huge amounts of electricity." AKA: "Smelting"
thinkcontext 2y ago
Good point about releasing co2 from the reservoir, thanks for the correction. I did not maintain that the aluminum was carbon free.