Large container ships burn through 16 tons of bunker oil per hour, and each journey can last up to 3 weeks - any idea what size of battery such a ship would need? I have no clue how to calculate that), but I'm guessing it would be completely impractical, even if we made huge strides in battery energy density.
I remember reading that they would have more limited range and lower top speeds, but that this might not be as much of a problem as it seems because the current routes are built around large container + long haul but that's not necessarily required (for all shipping at least).
[1] eg. https://maritime-executive.com/editorials/could-battery-powe...
Here's[2] a company offering a 1MWh battery in a standard 20ft container. EverGiven[3] carries ~20,000 standard containers. So, five EverGivens?
[1] https://www.traditionaloven.com/tutorials/energy/convert-ton...
[2] https://www.geebattery.com/battery/1mw-lithium-battery-energ... (The first one I found, without looking for the smallest).
- The energy density of LiIon batteries (or molten salt, or liquidy nitrogen etc) is roughly 100x smaller than that of gasoline/diesel/bunker fuel in weight terms and 40x smaller in volume terms
- The efficiency of electric motors is roughly 2x that of large diesel engines
So the amount of batteries needed for the same performance is 50x larger in weight and 20x larger in volume than the oil it carries (which for a big container ship is 6,000-10,000 tons I think). Which would be impractical.
I'm hoping that some of the battery technology currently under development (such as flow batteries, or aluminium-sulphur batteries) can trade space and weight for increased total capacity. A good battery for grid storage would probably work well for a container ship.
There are hundreds of nuclear powered ships already - submarines, Icebreakers, carriers, etc.
Aren't they all operated by militaries though? So if a conspiracy of crew members tries to steal some enriched fuel or fission products, it is legal to just shoot them or throw them in jail for decade for trying.
On board the ship itself, all the nuclear material is inside a running reactor, any would-be criminal would be dead before you could shoot them
Russian nuclear icebreakers are civilian ships, and people working at normal nuclear power stations are civilians too.
It is actually only relevant what happens in the part of the chain that handles nuclear fuel - thats the shipyard plus processing of spent fuel. But again, we do that for powerplants already.