this post was submitted on 10 Aug 2023
347 points (93.5% liked)

Technology

58303 readers
11 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 25 points 1 year ago* (last edited 1 year ago) (3 children)

Hydrogen sounds like a great idea for decarbonization until you get around to asking, "wait, where do we get the hydrogen from?" and realize that it's incredibly energy intensive and the most popular process releases a lot of CO2 directly.

https://en.wikipedia.org/wiki/Hydrogen_production

[–] [email protected] 14 points 1 year ago

Hydrogen is an energy storage, like a battery, so of course it requires a lot of energy to produce, that's the energy that you get back when consuming it (minus inefficiency losses of course).

The advantage of hydrogen over fossil fuels is that it can be produced from renewable energy, while fossil fuels cannot.

[–] [email protected] 11 points 1 year ago

There's a comment on another post with this article doing the math on this, and it seems like the net emissions (when you account for efficiencies) actually favour steam-reforming + fuel cells.

[–] [email protected] 9 points 1 year ago* (last edited 1 year ago)

Last time I checked, CO2 released at that altitude has 3x the effect on radiative forcing, so it's good that we're not dumping it up there. I know water is also a greenhouse gas, but I expect the residence time to be substantially lower than for CO2. So it would be a net positive as long as we're emitting on the ground the same amount of CO2 as emitted up there (we're probably emitting more, but probably not 3x more and it would be easier to capture at the exhaust than from up there)

PS: more on radiative forcing factors here https://sustainable.stanford.edu/sites/g/files/sbiybj26701/files/media/file/s3-radiative-forcing-rfi-memo_public.pdf