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That's interesting and sounds like a significant improvement. What I am really interested in though are sustainable fuels like ammonia, hydrogen or anything els

by ilaksh 3y ago

That's interesting and sounds like a significant improvement. What I am really interested in though are sustainable fuels like ammonia, hydrogen or anything else. Making fuel from solar and wind seems key to me. Because you need long term energy storage and batteries don't cut it.

gumby 3y ago
I don't think anyone seriously believes that ammonia or H2 are in any way sustainable fuels. But you're right that we definitely need something better than batteries for certain applications, particularly transport.
- sn0wf1re 3y ago
  This[1] was posted yesterday. I think people are hopeful that ammonia production can be made cheap enough to use as a seasonal battery or for applications such as planes or ships. https://news.ycombinator.com/item?id=38053586 https://news.ycombinator.com/item?id=38053586
- Gasp0de 3y ago
  Why not? With a 100% renewable energy supply, there needs to be a lot of overprovisioning. This means that in summer, we will have excess energy, which can be converted to hydrogen or other forms. This will easily be enough to get us through the few days per year where neither sun nor wind can deliver enough power. Efficiency doesn't matter much, since the energy is excess/free. What matters is the rest of the cost, e.g. building electrolyzers, hydrogen storage and power plants that are only used a few days per year.
  - gumby 3y ago
    Consider the two words: "sustainable" and "fuel". As a locally generated process input, H2 appears to make sense, say for steel production or yes, ammonia. But H2 is hard to store; best is to do so cryogenically which uses a lot of energy and is heavy. storig higher temperature H2 is more difficult (those crafty molecules are tiny!). The economics likely work for many industrial processes, but not for transport, much less grid power generation. The "fuel" part doesn't pencil out; I believe H2 fuel story are just a subsidy to the fossil fuel companies in order to get legislation passed. Compared to other fuels Ammonia isn't especially energetic, but for a large vessel with a lot of space it can work. But it's really toxic and harder to manage safely than buker fuel or jet fuel. "Sustainable" doesn't mean just its production but its overall risk to human life. It lacks adequate energy density to drive something like a car much less a plane, even if you were willing to have something as nasty as NH3 in your fragile, weight-sensitive vehicle. Don't take my word for it: Maersk, who is famously commissioning ammonia (and methanol) vessels, has publicly stated that these are not long term solutions but rather (they hope) a way to push the green agenda forward.
- ilaksh 3y ago
  Many people think they are sustainable. What fuels do you think are sustainable?
  - gumby 3y ago
    Look at my reply to Gasp0de. > What fuels do you think are sustainable? I really don't think we know yet (for transportation). The fuels we have are highly energetic (in particular by weight) because a lot of energy went into them to generate those tight bonds. Transportation fuels need a lot of important factors: energy density at a system level (energy per weight including storage), general safety at STP, etc. There have been some efforts to make ptroleum products from captured CO2, which might be a temporary bridge (by definition it's GHG neutral and can use renewable power) but burning these fuels produces other pollution beyond GHGs (thus are't sustainable) so they still need to be eliminated. Fortunately batteries appear viable for the middle of the curve, most wheeled vehicles. But at the extrema (ships, planes, and rockets), we need something that performs closer to what we have today and I don't see anything on the horizon.
    - ilaksh 3y ago
      I never said a single word about transportation. For urban cores, batteries are obviously quite viable today. What I am concerned about is energy storage for power grids or microgrids. Do you want to claim that hydrogen and ammonia can't work for this use case either, and that there is nothing viable? Implying that the most sustainable option is to just continue using fossils fuels. What I think is that there a ways to make both hydrogen and ammonia and other options very viable not only for grid storage but also for transportation. What's holding it back is a lack of critical thinking. This is because most people's views are dictated by social circumstances and then they subconsciously find ways to rationalize them. In other words, it's hard to get people on board with solving new problems related to using different energy sources, and so executives will invent reasons it can't work. What sort of fuel do you think makes sense to pursue for long term (months) energy storage?
- pfdietz 3y ago
  Of course they are sustainable.
  - gumby 3y ago
    Look at my reply to Gasp0de
    - pfdietz 3y ago
      What you wrote there is not responsive to my comment. You have not given any reason to think they are not sustainable. You are maybe arguing they aren't economical, but that's different (and also I contend wrong for each for some uses.) I don't think you've reached your opinion on the basis of adequate reasoning.

by ilaksh 3y ago

gumby 3y ago

I don't think anyone seriously believes that ammonia or H2 are in any way sustainable fuels. But you're right that we definitely need something better than batteries for certain applications, particularly transport.

sn0wf1re 3y ago
This[1] was posted yesterday. I think people are hopeful that ammonia production can be made cheap enough to use as a seasonal battery or for applications such as planes or ships. https://news.ycombinator.com/item?id=38053586 https://news.ycombinator.com/item?id=38053586
Gasp0de 3y ago
Why not? With a 100% renewable energy supply, there needs to be a lot of overprovisioning. This means that in summer, we will have excess energy, which can be converted to hydrogen or other forms. This will easily be enough to get us through the few days per year where neither sun nor wind can deliver enough power. Efficiency doesn't matter much, since the energy is excess/free. What matters is the rest of the cost, e.g. building electrolyzers, hydrogen storage and power plants that are only used a few days per year.
- gumby 3y ago
  Consider the two words: "sustainable" and "fuel". As a locally generated process input, H2 appears to make sense, say for steel production or yes, ammonia. But H2 is hard to store; best is to do so cryogenically which uses a lot of energy and is heavy. storig higher temperature H2 is more difficult (those crafty molecules are tiny!). The economics likely work for many industrial processes, but not for transport, much less grid power generation. The "fuel" part doesn't pencil out; I believe H2 fuel story are just a subsidy to the fossil fuel companies in order to get legislation passed. Compared to other fuels Ammonia isn't especially energetic, but for a large vessel with a lot of space it can work. But it's really toxic and harder to manage safely than buker fuel or jet fuel. "Sustainable" doesn't mean just its production but its overall risk to human life. It lacks adequate energy density to drive something like a car much less a plane, even if you were willing to have something as nasty as NH3 in your fragile, weight-sensitive vehicle. Don't take my word for it: Maersk, who is famously commissioning ammonia (and methanol) vessels, has publicly stated that these are not long term solutions but rather (they hope) a way to push the green agenda forward.
ilaksh 3y ago
Many people think they are sustainable. What fuels do you think are sustainable?
- gumby 3y ago
  Look at my reply to Gasp0de. > What fuels do you think are sustainable? I really don't think we know yet (for transportation). The fuels we have are highly energetic (in particular by weight) because a lot of energy went into them to generate those tight bonds. Transportation fuels need a lot of important factors: energy density at a system level (energy per weight including storage), general safety at STP, etc. There have been some efforts to make ptroleum products from captured CO2, which might be a temporary bridge (by definition it's GHG neutral and can use renewable power) but burning these fuels produces other pollution beyond GHGs (thus are't sustainable) so they still need to be eliminated. Fortunately batteries appear viable for the middle of the curve, most wheeled vehicles. But at the extrema (ships, planes, and rockets), we need something that performs closer to what we have today and I don't see anything on the horizon.
  - ilaksh 3y ago
    I never said a single word about transportation. For urban cores, batteries are obviously quite viable today. What I am concerned about is energy storage for power grids or microgrids. Do you want to claim that hydrogen and ammonia can't work for this use case either, and that there is nothing viable? Implying that the most sustainable option is to just continue using fossils fuels. What I think is that there a ways to make both hydrogen and ammonia and other options very viable not only for grid storage but also for transportation. What's holding it back is a lack of critical thinking. This is because most people's views are dictated by social circumstances and then they subconsciously find ways to rationalize them. In other words, it's hard to get people on board with solving new problems related to using different energy sources, and so executives will invent reasons it can't work. What sort of fuel do you think makes sense to pursue for long term (months) energy storage?
pfdietz 3y ago
Of course they are sustainable.
- gumby 3y ago
  Look at my reply to Gasp0de
  - pfdietz 3y ago
    What you wrote there is not responsive to my comment. You have not given any reason to think they are not sustainable. You are maybe arguing they aren't economical, but that's different (and also I contend wrong for each for some uses.) I don't think you've reached your opinion on the basis of adequate reasoning.