CATL Expects Oceanic Electric Ships in 3 Years

The recharging infrastructure for such a vessel would be an interesting challenge. Likewise if those batteries caught fire.

That's both amazing and hilarious just like filling a plane with hard drives is both insanely effective and just plain insane.

East Asia has extensive coastal medium-distance trade. There are so many islands and island nations. That's oceanic trade, but not transatlantic or trans-pacific long hauls.

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There are multiple electric ferries already in operation:

https://en.wikipedia.org/wiki/MV_Ampere

They are quite impressive but they are still very far away from your average ocean going cargo vessel.

... and energy densities of batteries will _stay_ well below that of tanks of hydrocarbons, as https://web.archive.org/web/20130204210054/http://h30565.www... explains.

Depends on the current fuel-to-payload ratio of the diesel ships. If it's 3% and batteries would push it to 10%, it's not a huge problem. But if it's 15% and batteries would push it to 50% you're losing a lot of capacity.

Ships are subject to so much drag that this is rarely a problem, only in emergency situations and there is not much that you can do to stop a vessel that weighs 100,000 tons or more except to run your engines in reverse and start praying to your deity. Regenerative braking for boats would be a complete waste.

There are some vessels that have single use emergency brakes, but the latest trend is to have motor 'pods' that are electrical and that can be used both for normal propulsion as well as to perform emergency stops that are quite impressive given the size of the vessels they are on. Typically an oceangoing vessel requires at least 3, but commonly 5 to 10 ship lengths to come to a full stop from moving forward under power. This is not necessarily because of limitations of the propulsion unit, but simply because stopping that much tonnage too fast would do as much damage as a collision would. With classical engines there is far more rotating mass so it would take much longer than with electrical propulsion to react before the beginning of the braking phase.

Not changing course is good though. Regenerative braking is only good because it increases the efficiency when you absolutely must slow down, but it would always be more efficient to slow down less.

Isn’t regenerative braking reclaiming otherwise wasted energy from necessary deceleration? Running the propeller in reverse would result in having to apply equal or greater energy to regain the current speed, so it’s a net loss of energy if I’m understanding the suggestion properly.

Wind, large surface area for solar

Also wave based generators that could also act as dampers/suspension and they wouldn’t steal energy from forward motion like wind would (depending on if you’re generating wind energy or using wind to buttress the batteries).

Ideally a combination of sails coupled with batteries and wave generators sounds like it would be very energy efficient.

Unfortunately, it's not even close. Maybe 1-2% in a highly optimistic scenario.

- 20k square meters of hull space

- If fully covered with solar panels, on a sunny day, you could expect 1-2 MWh (when averaging in night time)

- Current diesel engines typically output 60MWh continuously while underway.

And that's not factoring in the solar panels getting covered in salt over time and losing efficiency. Plus preventing the ship from actually loading / unloading cargo efficiently.

It's not just a matter of panel efficiency either. If we had magic panels that could absorb 100% of the suns power over the 20k sqm deck, it would only equate to about four times as much (8% of the overall power need).

Lithium is not scarce, and not a limiting factor for scaling up batteries.

There's more than enough lithium out there, more discovered every month, and the perception that we are limited by lithium is mostly out there because certain media sources are trying to help out there fossil fuel friends by delaying the energy interchange by a few years.

Whether battery ocean shipping containers make technical sense is a different question, but I wouldn't worry about lithium use!

There are examples of solar electric catamarans - but they are much smaller than a cargo vessel. It's not nothing, but we're some ways away.

I wouldn't underestimate what creative and dedicated engineers can accomplish.

No.

I’m too lazy to do it myself but 5 minutes of searching and calculating will show you that the area of solar panels required to move a ship is far, far, larger than the area of that ship.

Not to mention that a container ship’s deck is typically completely covered with, well, containers.

Also, lithium isn’t scarce.

No, but with wind it's possible. Either vertical windmills or sails with modern signal processing.

Honestly DJI and Boeing should get into this business. A boat's sail basically a plane's wing, aerodynamically speaking. They share a lot of similarities with endurance gliders.

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