this post was submitted on 13 Mar 2025
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Why run ammonia when you can just run liquid hydrogen? Why run liquid hydrogen when you can just run a nuclear reactor?
Hydrogen is definetly harder to store than ammonia and it takes a lot of energy to compress or liquify it.
And I certainly don't want commercial nuclear ships, because companies will just create "independent" companies that will "mysteriously" go bankrupt once a ship reaches end of life and needs to be decontaminated.
So the taxpayer would have to pay for the decomissioning costs.
It takes a lot of energy to convert hydrogen to ammonia and whatever challenges there are to handling and storing hydrogen, ammonia has its own. At least a hydrogen release isn't a toxic, polluting event.
Yes. Let's just get ahead of the game and nationalize shipping.
Ammonia has higher energy content than LH2. Easier storage, and easier boil off management/concerns.
Those are fair considerations. However, I think in the context of a massive cargo ship, a penalty on energy density might be worth it to avoid the risks associated with ammonia releases. Of course, a nuclear reactor powered ship would run on the highest energy density fuel and is arguably safer to operate than a ship that runs on ammonia.
LH2 can work well for commercial shipping. Use at pace of boil off. Ammonia toxicity is a bit overblown. The tiniest leak will smell strongly, and it leaks as a gas. The smell threshold is far below toxicity level. Go outside is a natural solution.
Ammonia and LH2 have tradeoffs. Compressed H2 in "trimaran pontoons" is an excellent solution that would permit sail assist as well. Nuclear is too expensive.
Nuclear marine propulsion is mainly used in naval warships, and it looks like there are some serious issues for their use in another context:
See also: Why nuclear-powered commercial ships are a bad idea | Bulletin of the Atomic Scientists
The serious issues in the articles you linked are essentially red tape and public perception, which have to be surmountable if we're taking global warming seriously.
I'm getting really fucking tired of seeing the fossil fuel industries' ~~cock~~propaganda in that person's mouth.
That's where most of the anti-nuclear sentiment comes from: because they don't like competition from a technology that is better than them in every way including cost of life per gigawatt hour...
Nuclear energy is only advocated by fossil fuel shills. It is perfect non-competitive solution to drill baby drill, because status quo for 15 years of development, followed by overpriced competition to fossil fuels after commissioning.
Nuclear powered ships cost an astronomical amount of money. At least $4B more than a diesel version. If you need to stay at sea for 6 months in strategic position, there is no other solution. But that is only purpose to spend that much.
Civilian control means nuclear proliferation/black market risks.
Hydrogen leaks like crazy
It does not leak like crazy. I know because I have experience engineering and operating high pressure electrolysis, storage, and fueling systems for hydrogen. Even when it does leak, what's nice about hydrogen is that it's not toxic to humans or pollutive to the environment, unlike ammonia or fossil fuels. Hydrogen leaks are easily mitigated with proven detection and ventilation techniques.
I thought hydrogen could leak through containers? On account of being so small?
Hydrogen will leak through a latex balloon, but it is not going to leak through the steel wall of a pressure vessel. The leak risk occurs at the various fitting connections in a hydrogen system, which is overcome by using the proper fittings.
instead of pouring it into your beer mug (or natural gas container) hoping it stays contained, you design a container that won't leak.
@CrimeDad @thedeadwalking4242 It leaks like crazy and it is a GHG 11x worse than CO2.
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment/_data/file/1067144/atmospheric-implications-of-increased-hydrogen-use.pdf
The GHG "problem" of H2 is that it competes with methane for breakdown of methane in atmosphere. If we use/leak less methane, then problem solved.
That is an interesting article, but the authors are clear that they don't know what to expect for hydrogen leakage in a developed hydrogen economy. Sure, hydrogen might be a greenhouse gas, but you can't really compare it to carbon dioxide because that's a waste product that we actively dispose of to the atmosphere. You can't really compare it to methane either because it's naturally abundant and the LEL is much higher. Relatively leaky valves and fittings are unfortunately acceptable in natural gas service. In other words, hydrogen leakage is barely tolerable, so we have no choice but to employ technology and techniques to prevent it.