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In 2005 there was similar hype around efficiently storing hydrogen, but using ammonia. Can't find any sources on why that didn't go anywhere though. https://ww

In 2005 there was similar hype around efficiently storing hydrogen, but using ammonia. Can't find any sources on why that didn't go anywhere though. https://www.sciencedaily.com/releases/2005/09/050907102549.htm https://www.sciencedaily.com/releases/2005/09/050907102549.h...

hannob 6y ago
Ammonia is currently considered as one of the more promising options for future shipping fuels. There are a number of projects planning to create green ammonia at scale, e.g. this: https://asianrehub.com/ https://asianrehub.com/ Ammonia is already made from hydrogen today, making that green is pretty straightforward, you just need enough clean electricity. Just get the hydrogen from electrolysis, the ammonia synthesis process itself is well established technology.
- corty 6y ago
  Ammonia is one of the less pleasant chemicals one could use. I'd rather have Hydrogen-exuding paste than Ammonia in an accident. The Hydrogen might explode. But the Ammonia definitely will hurt you.
  - kaliszad 6y ago
    Ammonia is quite ok. You can smell it :-) You can put it into water, where it is quite stable. We know how to handle it at industrial scale because of fertilizers.
    - diggernet 6y ago
      Yes, you can smell it, when drastically diluted in water (which, as you say, is stable) such as for a household cleaner. But in a concentrated form such as that required for use as fuel, if you smell it, it will kill you. Quickly.
      - corty 6y ago
        Also, water-free Ammonia is gaseous at room temperature, you have to transport it in pressurized containers. Should one of those rupture, all the Ammonia will boil off, creating a nice cloud of fun for all involved. Neutralizing it works by spraying acetic or hydrochloric acid, which is not quite as bad, but still quite ugly.
- Nasrudith 6y ago
  Why not just use a closed loop hydrocarbon from electricity system as a shipping fuel if you have excess power and a need for transit? The main theoretical point of hydrogen is very high specific energy per mass but it is essentially purest acidic gas and a pain. Bonding it to something else mitigates it so why 3 H per N instead of 4 H per C? Both are toxic gases at this point leaving ammonia's main advantage in the context being its own oderant.
  - hannob 6y ago
    The problem with every hydrocarbon-based fuel is that you need the carbon. You get that from CO2. But then you need to get the CO2. Where do you get it from? From a fossil-based plant? Well, ideally you'd want to get rid of those, not exactly smart to create incentives to keep them running. The alternative is either biomass (problematic) or direct air capture (expensive and inefficient). (Some insightful discussion on green methanol: https://www.youtube.com/watch?v=jXACyUxxBts https://www.youtube.com/watch?v=jXACyUxxBts ) With non-carbon based fuels like hydrogen or ammonia you skip that problem (air is 78% nitrogen, much easier to extract).
    - NickM 6y ago
      or direct air capture (expensive and inefficient) The big question in my mind is whether direct air capture is inherently expensive and inefficient...or if this is just a chicken/egg problem where we haven't invested time and money in making it cheaper because it's expensive, and it's expensive because we haven't invested time and money in making it cheaper. I don't know enough about physics and chemistry to answer the question on what the theoretical lower bound on cost might be.
      - jbay808 6y ago
        It's inherently expensive, because you have to undo the entropy loss of letting the CO2 diffuse into the atmosphere. It basically means running an expensive molecule sorting operation, whose cost has a floor set by the laws of thermodynamics, in advance of whatever else you wanted to do with the CO2.

hannob 6y ago

Ammonia is currently considered as one of the more promising options for future shipping fuels. There are a number of projects planning to create green ammonia at scale, e.g. this: https://asianrehub.com/ https://asianrehub.com/ Ammonia is already made from hydrogen today, making that green is pretty straightforward, you just need enough clean electricity. Just get the hydrogen from electrolysis, the ammonia synthesis process itself is well established technology.

corty 6y ago
Ammonia is one of the less pleasant chemicals one could use. I'd rather have Hydrogen-exuding paste than Ammonia in an accident. The Hydrogen might explode. But the Ammonia definitely will hurt you.
- kaliszad 6y ago
  Ammonia is quite ok. You can smell it :-) You can put it into water, where it is quite stable. We know how to handle it at industrial scale because of fertilizers.
  - diggernet 6y ago
    Yes, you can smell it, when drastically diluted in water (which, as you say, is stable) such as for a household cleaner. But in a concentrated form such as that required for use as fuel, if you smell it, it will kill you. Quickly.
    - corty 6y ago
      Also, water-free Ammonia is gaseous at room temperature, you have to transport it in pressurized containers. Should one of those rupture, all the Ammonia will boil off, creating a nice cloud of fun for all involved. Neutralizing it works by spraying acetic or hydrochloric acid, which is not quite as bad, but still quite ugly.
Nasrudith 6y ago
Why not just use a closed loop hydrocarbon from electricity system as a shipping fuel if you have excess power and a need for transit? The main theoretical point of hydrogen is very high specific energy per mass but it is essentially purest acidic gas and a pain. Bonding it to something else mitigates it so why 3 H per N instead of 4 H per C? Both are toxic gases at this point leaving ammonia's main advantage in the context being its own oderant.
- hannob 6y ago
  The problem with every hydrocarbon-based fuel is that you need the carbon. You get that from CO2. But then you need to get the CO2. Where do you get it from? From a fossil-based plant? Well, ideally you'd want to get rid of those, not exactly smart to create incentives to keep them running. The alternative is either biomass (problematic) or direct air capture (expensive and inefficient). (Some insightful discussion on green methanol: https://www.youtube.com/watch?v=jXACyUxxBts https://www.youtube.com/watch?v=jXACyUxxBts ) With non-carbon based fuels like hydrogen or ammonia you skip that problem (air is 78% nitrogen, much easier to extract).
  - NickM 6y ago
    or direct air capture (expensive and inefficient) The big question in my mind is whether direct air capture is inherently expensive and inefficient...or if this is just a chicken/egg problem where we haven't invested time and money in making it cheaper because it's expensive, and it's expensive because we haven't invested time and money in making it cheaper. I don't know enough about physics and chemistry to answer the question on what the theoretical lower bound on cost might be.
    - jbay808 6y ago
      It's inherently expensive, because you have to undo the entropy loss of letting the CO2 diffuse into the atmosphere. It basically means running an expensive molecule sorting operation, whose cost has a floor set by the laws of thermodynamics, in advance of whatever else you wanted to do with the CO2.