Very interesting.
Thanks for posting.

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Kawasaki is already working on an entire ecosystem of hydrogen-related products and technologies across its span of products. These include enormous hydrogen-fueled combustion engines for ships, which the company intends to demonstrate by 2025, and even hydrogen-powered jet aircraft that are penciled in for launch sometime around 2035.

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While it’s not completely eco-friendly—the presence of nitrogen in the air means there are also NOx emissions from a hydrogen-fueled combustion engine—most of the exhaust would be nothing more than water vapor.

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Japan has long had interesting projects to extract things from seawater.

Pre-WW-II Japan had a plant to extract Magnesium from seawater to make lighter, stronger aluminum alloys.

Today has a program to extract Uranium from seawater, and is heading toward less than $200 per kilogram.

Is there an as yet unknown sea organism that emits hydrogen gas?

The “ozone hole” pushers claimed that only humans made chloro-bromo-hydrocarbon chemicals (Freons)
then sea life gas emissions were found (no one had looked before)

When I was researching rare earth carbides, I came upon the fact that some shell building sea life collected and concentrated rare earths from the sea water and used it in their shells, but it was not apparent that these shells were measurably stronger.