4 ms·

"The amount of electricity needed to power these technologies would be greater than the entire world’s electricity demand today" This is where the argument fal

"The amount of electricity needed to power these technologies would be greater than the entire world’s electricity demand today" This is where the argument falls off. For what its worth I think they are right in the sense that relying solely on carbon capture is bad economics, but having it in the mix makes a tonne of sense. I do expect carbon capture to become more efficient over time just as much as I expect energy to become more abundant, and part of that energy budget should go towards capturing the carbon output into the environment from legacy technologies.

toomuchtodo 3y ago
Enough sunlight falls on Earth every 2 minutes to power humanity for a year [1]. If we need more power, we construct additional renewables. We will need to generate enough aggregate power in order to sequester all of the excess carbon emitted into the atmosphere since the beginning of the industrial age. When the price of power goes to zero or negative, that is the ideal time for batteries to charge that provide power to carbon capture facilities. Of course, we should still be leaning into generation and consumption that does not emit carbon. Otherwise we continue to rack up carbon debt we will have to pay back with future clean energy. [1] https://www.ku.ac.ae/two-minutes-of-sun-enough-to-power-a-year-s-usage-of-humanity-gulf-news https://www.ku.ac.ae/two-minutes-of-sun-enough-to-power-a-ye...
- pests 3y ago
  Covering just 20% of the Sahara with solar panels causes a 1.5 C increase in global temperatures. Solar panels are dark, and dark absorbs heat. Solar panels are what, not even 30% efficient yet? So for every watt generated of useful energy, is two watts of extra heat. Not a problem small scale, definitely something to think about long term. Similar feedback loop to ice sheets melting exposing darker land and ocean beneath. Also explored in the sci-fi book "Project Hail Mary"
  - deleted 3y ago
    [deleted]
  - kragen 3y ago
    [citation needed] also though if we're talking about such mega-engineering projects you can float them on the ocean, which has a lower albedo than solar panels. or use some of the energy to make a lot of white plastic netting and drape it over a low-albedo region
    - pests 3y ago
      https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020GL090789 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/202... Don't quote me on the exact numbers, I wrote my original post from memory of an article summarizing the above paper but I never read the actual paper and do not know the accuracy of the claims.
      - kragen 3y ago
        thanks, this is great! it looks like the effects are complex enough that you could probably have the opposite effect just by choosing a different desert; it's not just a simple additive thermal forcing model as i was assuming
  - Workaccount2 3y ago
    I like how you frame "covering 20% of the Sahara" as a "just". Like it would be some trivial feat easily accomplished. For reference, 20% of the Sahara is around the size of Mexico.
    - pests 3y ago
      That comes straight from an article[0] I do admit I do not know if it accurately quotes its source but it was not just a made up example. It is also relevent to the story of Project Hail Mary by Andy Weir (2021) where they needed 2 trillion square meters of solar panels for an emergency. The study quoted in the article below was in 2018, book released in 2021, the article itself in 2021, might be some covergent evolution to the story. [0] https://theconversation.com/solar-panels-in-sahara-could-boost-renewable-energy-but-damage-the-global-climate-heres-why-153992 https://theconversation.com/solar-panels-in-sahara-could-boo...

toomuchtodo 3y ago

Enough sunlight falls on Earth every 2 minutes to power humanity for a year [1]. If we need more power, we construct additional renewables. We will need to generate enough aggregate power in order to sequester all of the excess carbon emitted into the atmosphere since the beginning of the industrial age. When the price of power goes to zero or negative, that is the ideal time for batteries to charge that provide power to carbon capture facilities. Of course, we should still be leaning into generation and consumption that does not emit carbon. Otherwise we continue to rack up carbon debt we will have to pay back with future clean energy. [1] https://www.ku.ac.ae/two-minutes-of-sun-enough-to-power-a-year-s-usage-of-humanity-gulf-news https://www.ku.ac.ae/two-minutes-of-sun-enough-to-power-a-ye...

pests 3y ago
Covering just 20% of the Sahara with solar panels causes a 1.5 C increase in global temperatures. Solar panels are dark, and dark absorbs heat. Solar panels are what, not even 30% efficient yet? So for every watt generated of useful energy, is two watts of extra heat. Not a problem small scale, definitely something to think about long term. Similar feedback loop to ice sheets melting exposing darker land and ocean beneath. Also explored in the sci-fi book "Project Hail Mary"
- deleted 3y ago
  [deleted]
- kragen 3y ago
  [citation needed] also though if we're talking about such mega-engineering projects you can float them on the ocean, which has a lower albedo than solar panels. or use some of the energy to make a lot of white plastic netting and drape it over a low-albedo region
  - pests 3y ago
    https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020GL090789 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/202... Don't quote me on the exact numbers, I wrote my original post from memory of an article summarizing the above paper but I never read the actual paper and do not know the accuracy of the claims.
    - kragen 3y ago
      thanks, this is great! it looks like the effects are complex enough that you could probably have the opposite effect just by choosing a different desert; it's not just a simple additive thermal forcing model as i was assuming
- Workaccount2 3y ago
  I like how you frame "covering 20% of the Sahara" as a "just". Like it would be some trivial feat easily accomplished. For reference, 20% of the Sahara is around the size of Mexico.
  - pests 3y ago
    That comes straight from an article[0] I do admit I do not know if it accurately quotes its source but it was not just a made up example. It is also relevent to the story of Project Hail Mary by Andy Weir (2021) where they needed 2 trillion square meters of solar panels for an emergency. The study quoted in the article below was in 2018, book released in 2021, the article itself in 2021, might be some covergent evolution to the story. [0] https://theconversation.com/solar-panels-in-sahara-could-boost-renewable-energy-but-damage-the-global-climate-heres-why-153992 https://theconversation.com/solar-panels-in-sahara-could-boo...