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What are other options for ships if fossil fuels were phased out? Big batteries? https://www.resilience.org/stories/2022-07-28/making-waves-electric-ships-are-

What are other options for ships if fossil fuels were phased out? Big batteries? https://www.resilience.org/stories/2022-07-28/making-waves-electric-ships-are-sailing-ahead/ https://www.resilience.org/stories/2022-07-28/making-waves-e... Hydrogen fuel? https://en.m.wikipedia.org/wiki/Hydrogen-powered_ship https://en.m.wikipedia.org/wiki/Hydrogen-powered_ship Yeah, those options seem simpler.

jasonwatkinspdx 3y ago
Sustainable fuels. It's the solution long haul aviation is coalescing around.
- Manuel_D 3y ago
  Synthetic fuel has a lot of difficulties. One, it requires hydrogen as an input which is typically produced through steam reformation [1], a process that emits CO2. Electrolysis is less efficient and hard to scale as equipment is subject to intense corrosion. Second, CO2 is at very low concentrations in the atmosphere. Direct atmospheric carbon sequestration is expensive and slow. The biggest startup in the synthetic fuel business is behind schedule and is struggling to solve these two main challenges [2]. 1. https://en.wikipedia.org/wiki/Steam_reforming https://en.wikipedia.org/wiki/Steam_reforming 2. https://www.technologyreview.com/2022/04/25/1050899/prometheus-fuels-startup-carbon-neutral/ https://www.technologyreview.com/2022/04/25/1050899/promethe...
  - xorcist 3y ago
    Ammonia?
    - Manuel_D 3y ago
      Ammonia also requires hydrogen as an input. Ammonia is essentially a storage mechanism for hydrogen, eliminating the need for cryogenic or compressed storage. Basically, you need to find a carbon-neutral alternative to the Haber process [1] to produce ammonia as fuel. 1. https://en.wikipedia.org/wiki/Haber_process https://en.wikipedia.org/wiki/Haber_process
      - hef19898 3y ago
        Which we have already. And that wouod be a great solution to the problem of storing electricity / energy. And it could even use, partially, existing gas infrastructure. Green hydrogen absolutey is a thing, bow we just need to deploy it at scale.
        Manuel_D 3y ago
        No, almost all of our ammonia is produced via the Haber process which emits carbon dioxide. Less than a tenth of one percent of our hydrogen is produced via green hydrogen: > As of 2021, green hydrogen accounted for less than 0.04% of total hydrogen production. Its cost relative to hydrogen derived from fossil fuels is the main reason green hydrogen is in less demand. For example, hydrogen produced by electrolysis powered by solar power was about 25 times more expensive than that derived from hydrocarbons in 2018. https://en.wikipedia.org/wiki/Green_hydrogen https://en.wikipedia.org/wiki/Green_hydrogen
        hef19898 3y ago
        I said we mist roll it out at scale, didn't I? The tech is there, and it works, now we have to build it. You know, like Musk did with EVs and charging networks.
        Manuel_D 3y ago
        And as per the article, it's 25 times more expensive than existing hydrogen sources. By comparison, the economics nuclear powered ships are not that much worse than conventional propulsion: https://en.wikipedia.org/wiki/NS_Savannah#Economics_of_nuclear_propulsion https://en.wikipedia.org/wiki/NS_Savannah#Economics_of_nucle...
        hef19898 3y ago
        Of course not. The right mix is important. But honestly, I reached the point where I claim the same "just build it" approach the pro-nuclear crowd is using regardless of data and facta. Especially since I know from a project I was involved in before COVID hit, that green hydrogen produced PV is absolutely feasible and commercially viable. To do so at tue scale needed requires political action and subsidies, and the tech has still a lot of room for improvement. I say this is good news.
  - p1mrx 3y ago
    We need to massively scale up green hydrogen production under basically any scenario where climate change is avoided. Hydrogen is an input for many industrial and agricultural processes.
  - jasonwatkinspdx 3y ago
    Biofuels do not require hydrogen or atmospheric CO2 capture, well beyond growing plants. Also something I learned recently is that the idea that biofuels are a no go because they compete with food is a simplistic deflection. Looking at Brazil as an example the biofuel crops like sugarcane and groundnuts are grown in marginal land in the south that wasn't being used for agriculture. The main driver of Amazonian deforestation is cattle ranching.
    - Manuel_D 3y ago
      Biofuels produced by growing plants is limited by the available biomass. Brazil powers it's automobiles with biofuel, but not ships. And more importantly, Brazil is a huge country with massive amounts of arable land.
deleted 3y ago
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jasonwatkinspdx 3y ago

Sustainable fuels. It's the solution long haul aviation is coalescing around.

Manuel_D 3y ago
Synthetic fuel has a lot of difficulties. One, it requires hydrogen as an input which is typically produced through steam reformation [1], a process that emits CO2. Electrolysis is less efficient and hard to scale as equipment is subject to intense corrosion. Second, CO2 is at very low concentrations in the atmosphere. Direct atmospheric carbon sequestration is expensive and slow. The biggest startup in the synthetic fuel business is behind schedule and is struggling to solve these two main challenges [2]. 1. https://en.wikipedia.org/wiki/Steam_reforming https://en.wikipedia.org/wiki/Steam_reforming 2. https://www.technologyreview.com/2022/04/25/1050899/prometheus-fuels-startup-carbon-neutral/ https://www.technologyreview.com/2022/04/25/1050899/promethe...
- xorcist 3y ago
  Ammonia?
  - Manuel_D 3y ago
    Ammonia also requires hydrogen as an input. Ammonia is essentially a storage mechanism for hydrogen, eliminating the need for cryogenic or compressed storage. Basically, you need to find a carbon-neutral alternative to the Haber process [1] to produce ammonia as fuel. 1. https://en.wikipedia.org/wiki/Haber_process https://en.wikipedia.org/wiki/Haber_process
    - hef19898 3y ago
      Which we have already. And that wouod be a great solution to the problem of storing electricity / energy. And it could even use, partially, existing gas infrastructure. Green hydrogen absolutey is a thing, bow we just need to deploy it at scale.
      - Manuel_D 3y ago
        No, almost all of our ammonia is produced via the Haber process which emits carbon dioxide. Less than a tenth of one percent of our hydrogen is produced via green hydrogen: > As of 2021, green hydrogen accounted for less than 0.04% of total hydrogen production. Its cost relative to hydrogen derived from fossil fuels is the main reason green hydrogen is in less demand. For example, hydrogen produced by electrolysis powered by solar power was about 25 times more expensive than that derived from hydrocarbons in 2018. https://en.wikipedia.org/wiki/Green_hydrogen https://en.wikipedia.org/wiki/Green_hydrogen
        hef19898 3y ago
        I said we mist roll it out at scale, didn't I? The tech is there, and it works, now we have to build it. You know, like Musk did with EVs and charging networks.
        Manuel_D 3y ago
        And as per the article, it's 25 times more expensive than existing hydrogen sources. By comparison, the economics nuclear powered ships are not that much worse than conventional propulsion: https://en.wikipedia.org/wiki/NS_Savannah#Economics_of_nuclear_propulsion https://en.wikipedia.org/wiki/NS_Savannah#Economics_of_nucle...
        hef19898 3y ago
        Of course not. The right mix is important. But honestly, I reached the point where I claim the same "just build it" approach the pro-nuclear crowd is using regardless of data and facta. Especially since I know from a project I was involved in before COVID hit, that green hydrogen produced PV is absolutely feasible and commercially viable. To do so at tue scale needed requires political action and subsidies, and the tech has still a lot of room for improvement. I say this is good news.
- p1mrx 3y ago
  We need to massively scale up green hydrogen production under basically any scenario where climate change is avoided. Hydrogen is an input for many industrial and agricultural processes.
- jasonwatkinspdx 3y ago
  Biofuels do not require hydrogen or atmospheric CO2 capture, well beyond growing plants. Also something I learned recently is that the idea that biofuels are a no go because they compete with food is a simplistic deflection. Looking at Brazil as an example the biofuel crops like sugarcane and groundnuts are grown in marginal land in the south that wasn't being used for agriculture. The main driver of Amazonian deforestation is cattle ranching.
  - Manuel_D 3y ago
    Biofuels produced by growing plants is limited by the available biomass. Brazil powers it's automobiles with biofuel, but not ships. And more importantly, Brazil is a huge country with massive amounts of arable land.

deleted 3y ago

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