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Iceland has boiling hot water at the surface and so doesn’t need to drill far to reach hot rocks do to all the volcanism there. This does not apply to the vast

Iceland has boiling hot water at the surface and so doesn’t need to drill far to reach hot rocks do to all the volcanism there. This does not apply to the vast majority of the world

mirekrusin 2y ago
Are deepsea power cables from Iceland feasable or they'd have to store it as ie. hydrogen to send over?
- Reason077 2y ago
  Feasable, and the concept has been proposed, but doesn't look likely to be built in the near future. There are still lower hanging (more profitable) fruit when it comes to building undersea HVDC cables. https://en.wikipedia.org/wiki/Icelink https://en.wikipedia.org/wiki/Icelink
  - jfengel 2y ago
    Seems like one might hold off on underseas power cables until we figure out how to keep Russian and Chinese ships from having so many accidents.
    - adgjlsfhk1 2y ago
      power cables are a lot less vulnerable than fiber since cutting a cable carrying 500kv DC will do nasty things to whatever you're trying to cut with
      - appointment 2y ago
        Estlink 2 (650MW, 450 kV) has been cut twice in a year, with months-long outages in both cases.
- thinkcontext 2y ago
  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.
- thworp 2y ago
  We do have the technology to build HVDC cables from Iceland to Britain / Norway and we can expect the loss of this grid-to-grid interconnect to be < 5%. It's a different question entirely if it is feasible. It would be the longest sub-sea power cable ever, and the projected cost of $4 billion might be much too low. In the current situation Europe would profit immensely by sending excess renewable energy to Iceland's pumped hydro and Aluminium smelters while using their geothermal baseload capacity. But in 15 years that might no longer be the case and by then the investment would not have paid off and there might be regret that the money wasn't spent on a different HVDC line like another North Africa - Europe link or Bulgaria - Caucasus (which has a lot of undeveloped hydro potential).
deleted 2y ago
[deleted]
glenstein 2y ago
Well the question was "Iceland has profitable geothermal, no?" and your answer appears to be yes. Which is important because it means the upshot is that there are viable applications, which contrasts against the argument that lack of generalized solution means we need to reject it wholesale.
- SkiFire13 2y ago
  The point likely was that even though both are "geothermal" they aren't really in the same category, so facts about one may not apply to the other.
  - glenstein 2y ago
    Here's a link to a map of geothermal hotspots comparable to Iceland. There seems to be a lot in the same category. https://www.edengeothermal.com/about/geothermal-energy/worldwide-potential/ https://www.edengeothermal.com/about/geothermal-energy/world...
- caminante 2y ago
  Not quite. The original comment (by @animats) specified shallow (viable) versus deep (unviable). > nobody seems to have a profitable deep geothermal power operation. That nuance got lost.
  - citadel_melon 2y ago
    The original comment stated that shallow geothermal can be useful for heating, but did not say anything about shallow geothermal electricity generation.
    - caminante 2y ago
      No. See the first paragraph. [0] The reference explicitly gets into "deep geothermal" (i.e., EGS) and talks about power applications that are viable because of limited drilling (i.e., shallow). > The more than 1 gigawatt of geothermal power currently produced globally — from California to Iceland to the Philippines — relies nearly exclusively on such natural outpourings of the earth’s heat. The building heat comment is just a reference to another residential/C&I application with ground loops. They're not dismissing or not acknowledging the grid-scale power applications. [0] https://news.ycombinator.com/item?id=43234465 https://news.ycombinator.com/item?id=43234465
Galatians4_16 2y ago
US has quite a few hot springs, especially in southwestern states.
- abracadaniel 2y ago
  SciShow did an interesting video on geothermal potential/drawbacks of Yellowstone. https://youtu.be/rqkJiMDAIpA https://youtu.be/rqkJiMDAIpA

Iceland has boiling hot water at the surface and so doesn’t need to drill far to reach hot rocks do to all the volcanism there. This does not apply to the vast majority of the world

mirekrusin 2y ago

Are deepsea power cables from Iceland feasable or they'd have to store it as ie. hydrogen to send over?

Reason077 2y ago
Feasable, and the concept has been proposed, but doesn't look likely to be built in the near future. There are still lower hanging (more profitable) fruit when it comes to building undersea HVDC cables. https://en.wikipedia.org/wiki/Icelink https://en.wikipedia.org/wiki/Icelink
- jfengel 2y ago
  Seems like one might hold off on underseas power cables until we figure out how to keep Russian and Chinese ships from having so many accidents.
  - adgjlsfhk1 2y ago
    power cables are a lot less vulnerable than fiber since cutting a cable carrying 500kv DC will do nasty things to whatever you're trying to cut with
    - appointment 2y ago
      Estlink 2 (650MW, 450 kV) has been cut twice in a year, with months-long outages in both cases.
thinkcontext 2y ago
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.
thworp 2y ago
We do have the technology to build HVDC cables from Iceland to Britain / Norway and we can expect the loss of this grid-to-grid interconnect to be < 5%. It's a different question entirely if it is feasible. It would be the longest sub-sea power cable ever, and the projected cost of $4 billion might be much too low. In the current situation Europe would profit immensely by sending excess renewable energy to Iceland's pumped hydro and Aluminium smelters while using their geothermal baseload capacity. But in 15 years that might no longer be the case and by then the investment would not have paid off and there might be regret that the money wasn't spent on a different HVDC line like another North Africa - Europe link or Bulgaria - Caucasus (which has a lot of undeveloped hydro potential).

deleted 2y ago

[deleted]

glenstein 2y ago

Well the question was "Iceland has profitable geothermal, no?" and your answer appears to be yes. Which is important because it means the upshot is that there are viable applications, which contrasts against the argument that lack of generalized solution means we need to reject it wholesale.

SkiFire13 2y ago
The point likely was that even though both are "geothermal" they aren't really in the same category, so facts about one may not apply to the other.
- glenstein 2y ago
  Here's a link to a map of geothermal hotspots comparable to Iceland. There seems to be a lot in the same category. https://www.edengeothermal.com/about/geothermal-energy/worldwide-potential/ https://www.edengeothermal.com/about/geothermal-energy/world...
caminante 2y ago
Not quite. The original comment (by @animats) specified shallow (viable) versus deep (unviable). > nobody seems to have a profitable deep geothermal power operation. That nuance got lost.
- citadel_melon 2y ago
  The original comment stated that shallow geothermal can be useful for heating, but did not say anything about shallow geothermal electricity generation.
  - caminante 2y ago
    No. See the first paragraph. [0] The reference explicitly gets into "deep geothermal" (i.e., EGS) and talks about power applications that are viable because of limited drilling (i.e., shallow). > The more than 1 gigawatt of geothermal power currently produced globally — from California to Iceland to the Philippines — relies nearly exclusively on such natural outpourings of the earth’s heat. The building heat comment is just a reference to another residential/C&I application with ground loops. They're not dismissing or not acknowledging the grid-scale power applications. [0] https://news.ycombinator.com/item?id=43234465 https://news.ycombinator.com/item?id=43234465

Galatians4_16 2y ago

US has quite a few hot springs, especially in southwestern states.

abracadaniel 2y ago
SciShow did an interesting video on geothermal potential/drawbacks of Yellowstone. https://youtu.be/rqkJiMDAIpA https://youtu.be/rqkJiMDAIpA