[Manuel_D]

Ships running off natural gas are nothing new. LNG carriers have been propelled by natural gas for decades. The real challenge is producing carbon-neutral natural gas, which your link says nothing about.

Synthetic natural gas has all the same problems as green hydrogen, with the added challenge of sequestering carbon from the atmosphere. It's only been cheaply produced using byproduct CO2 from industrial processes. Which isn't actually carbon-neutral, it's just using CO2 that would have been released into the atmosphere anyway.

[hef19898]

There you go:

https://www.valves-community.com/en/cryogenic-air-gases/synt...

But honestly, why am I doing your internet searches for you? And why don't you know any of this already?

[Manuel_D]

That plant is not sequestering atmospheric carbon dioxide. It's using waste carbon dioxide from a nearby biomass plant. This is far less challenging than removing CO2 from the atmosphere.

But unfortunately this method does not scale. The amount of fuel produced would be limited by the amount of carbon sequestered by plants. You'd be cutting down forests faster than they replenish if you tried to fuel cargo ships with this method.

> And why don't you know any of this already?

I do, and unlike you I understand how existing power to gas prototypes are using biomass or industrial byproduct CO2 rather than direct atmospheric sequesteration. This is sidestepping the most challenging part of producing synthetic hydrocarbons on a large scale.

Prometheus Fuels are the main player in attempting to solve direct atmospheric sequesteration of carbon dioxide. But they've still not delivered on that objective.

[hef19898]

And the last small scale nuclear reactor project, NuScale, was completely cancelled. So the amount of power produced by this reactor type seems rather limited, trending to zero even. And guess what, we need snall reactors to power ships, reactors we don't have (no, those half dozen Russian ones don't count).

See how this game can be olqyed in both directions? Difference being, all the real money, and industry, is going for green fuels and not nuclear power when it comes to ships. I tend to believe those people.

[Manuel_D]

NuScale wasn't building maritime propulsion.

Again, how many ships have been powered by green fuels? How many have been powered nuclear reactors? One of those is infinitely larger than the other. One of these technologies has over half a century of real world usage.

Comparing white papers about synthetic fuels with the cost history of actual nuclear powered ships that were built and operated for a decade or longer is comparing apples to oranges.

[ZeroGravitas]

Green fuel ships exist now. They're still in the early stages but plenty of big names in the business are putting their weight behind then.

Plenty of "normal" ships are already hybrid electric like trains, so swapping out the diesel generator isn't particularly a science project and doesn't affect the already electric propellors.

You mostly need a financial incentive to burn clean methanol, ammonia or whatever. That's the hard part.

[Manuel_D]

List some examples of cargo ships powered by green fuels that are presently in operation. Not small prototype ships, but green fuel powered ships comparable in capacity to the NS Savannah and other nuclear powered civilian ships: https://en.m.wikipedia.org/wiki/Nuclear_marine_propulsion#Ci...

[hef19898]

You just don't get it, do you? There is no readily available reactor tech suitable for commercial maritime use at the moment, none.

We do have technology so to produce green fuel for ships, and the whole shipping industry, from carriers to builders, is pursuing that in their goal of carbon neutral in 2050.

Of course there is still the possibility of those people being oart of a grand anti-nuclear conspiracy. Or they analyzed the tech and costs and came to an informed solution, one that is now global policy. You pick.

[Manuel_D]

> There is no readily available reactor tech suitable for commercial maritime use at the moment, none.

You realize there's a nuclear powered cargo ship in operation right now: https://en.m.wikipedia.org/wiki/Sevmorput

This technology not only exists, it's being used presently. And that's on top of the other three nuclear cargo ships that were previously built. We still have those proven designs.

> We do have technology so to produce green fuel for ships, and the whole shipping industry,

We do not. Existing synthetic gas plants are not capturing CO2 from the atmosphere. They are either using biomass or industrial byproduct CO2. The former of which does not scale, the latter is not truly carbon free it's just using carbon that would have been released into the atmosphere anyway. Neither is a pathway to producing green fuels at scale. Startups are pursuing atmospheric carbon sequestration, but it's proven elusive so far.