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HPsquared
Those will need some major fire protection. I wonder what the engineering features look like.
pinkgolem
LFP is no worse then wood and a lot better then an gasoline fire
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jeffrallen
The problem with fighting electric battery fires is finding enough water to cool them. Where oh where could a ferry find vast quantities of water? :)
mystified5016
Outside the boat. You need power to get water into the boat, which poses a problem when your power generator is on fire
wakawaka28
Battery fires are generally toxic and unextinguishable. That is the real problem. The pollution of water and air is too often overlooked when it comes to these fires, and the health risks associated with that very toxic crap are not well-understood.
thebruce87m
Anybody talking about “battery fires” without specifying the chemistry is just showing their ignorance.

There are multiple different chemistries. Go look up the guy drilling into LFP batteries on YouTube.

Edit: https://m.youtube.com/watch?v=D8xNjz73p80

HPsquared
Fair, maybe the protection is more of the "preventive" sort. But they haven't published specifics of which chemistry it is, to my knowledge.
ChrisMarshallNY
I remember taking that same run on a hydrofoil, back in the 1960s or '70s.
Rygian
Preempting the "why not hydrogen" comments:

Always a good time to refer to "The Hydrogen Ladder" (version 5.0 nowadays):

https://www.linkedin.com/pulse/hydrogen-ladder-version-50-mi...

In this case, the alternative of using hydrogen for the "Local Ferries" use case would be in class F (almost uncompetitive) and the recommended alternative is indeed electric powertrains.

gwbas1c
I came across an article about a hydrogen ferry a month or so ago. I think the ferry was somewhere in northwestern Europe, perhaps on the Nordic peninsula.

One major problem is that, due to physics, hydrogen containers leak... a lot. The hydrogen losses from transporting and storing the hydrogen for the ferry were phenomenal. I guess it's impossible to truly seal hydrogen via a valve because it's molecule is so tiny that it can wiggle through the best valves we can make.

walrus01
Leakage and hydrogen tank pressures, filling systems are why I think consumers should never own hydrogen fuel cell cars. Ever seen how many people manage to fill their gas car with diesel or vice versa? How careless people can be filling gasoline into approved 5 gallon cans? The number of people driving off from gas stations with the nozzle and hose still stuck in their cars?

And now people want to give the average driver access to hydrogen refueling apparatus? Shocking.

gwbas1c
> The number of people driving off from gas stations with the nozzle and hose still stuck in their cars?

I've never seen that happen.

But, I can't seem to fill a gas can without a drip getting on the side.

walrus01
It happens often enough that gas pump hoses are made with a special breakaway mechanism...
fragmede
Even if you've never personally seen such a situation, a trip down your chosen video platform (YouTube/Facebook/Instagram/TikTok) should convince you it happens way too often.
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7e
SF has made it work in a six month trial in 2024: https://www.power-technology.com/news/san-francisco-welcomes...

It all depends on the cost of the hydrogen, and green hydrogen costs will drop as spilled wind and solar proliferate.

Rygian
due to round-trip efficiency, the running cost of green hydrogen will always be twice as expensive as just using the electricity directly for the end purpose. And where batteries are feasible, they are cheaper amortized than the equivalent hydrogen infrastructure.
baq
There's an electric ferry service between Iceland and Vestmannaeyjar - it's very nice. Quiet and doesn't smell of ship diesel.

The charging port and plug are quite something, too.

jeffrallen
If it stays docked on one side at night hooked to the grid and offering grid stabilization services and charges on the other, could it be a net energy importer?

Asking for a friend... :)

zwieback
That's very cool. In Oregon we have an electric ferry across the Willamette but it has overhead power lines, like a train.
seanalltogether
I wonder how well a flywheel would work in this type of application. Journeys are short, presumably the flywheel can charge up faster then a normal battery. Maybe it's just too dangerous to put on a boat with passengers.
madphilosopher
A flywheel has a lot of angular momentum. Of course, that's the point. On buses, the axis of the flywheel is oriented in the vertical axis so that the bus can turn corners or change horizontal directions without causing gyroscopic precession. But on a ship that pitches and rolls, the external force on the flywheel will cause a torque that changes the direction of the angular momentum of the flywheel. A roll would do something like pitch the ship forward or backward (depending on the direction that the flywheel spins), which would really mess up the ship's motion, I imagine. The preceding is just my thought experiment on what would happen to such a ship. Let's build one!
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