Ha, that&#x27;s like the quote: &quot;Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway.&quot;

That&#x27;s easy to work out from the parent comment. They conclude that 16,000 tons of batteries are needed for propulsion, with a total capacity of 3GWh.For a typical 40kton cargo ship, that leaves 24,000 tons for more batteries, for a energy cargo capacity of 4.5GWh. The average US citizen uses ~770,000 BTUs of energy per day, or 0.23MWh. This &quot;energy cargo&quot; of this ship would provide the entire energy needs of a city of 20k people for one day. (I am being a little unfair, by assuming that everyone uses electricity for all of their energy needs in this scenario).

A japanese startup is working on a (surprisingly small) battery energy &quot;tanker&quot;:<a href="https:&#x2F;&#x2F;power-x.jp&#x2F;en&#x2F;newsroom&#x2F;Introducing-the-world%E2%80%99s-first-battery-tankerX" rel="nofollow">https:&#x2F;&#x2F;power-x.jp&#x2F;en&#x2F;newsroom&#x2F;Introducing-the-world%E2%80%9...</a>I think there are some startups working on cargo train &quot;tankers&quot; in the US too.An idea I had after seeing the tanker concept was to have the battery carrier also serve as a generator via wind power. If its a huge ship I suppose you could just stick a turbine on it and go where the wind is blowing. I think a more fun concept is generating power off of a smaller scale cat- or trimaran generating both propulsion and power by sailing conventionally.

Panamax ship is 5000 teu (twenty foot shipping container equivalent)I think you get about 4 MWh per TEU ( based on my 12V 100Ah battery)so about 20 GWh

Those are some big numbers. It makes me think of a crazy thought experiment:How many MW could a container ship carry by literally shipping energy stored in batteries?As in they fill up entirely with batteries, sail to a desert, plug into a cable to charge on cheap solar, charge up, sail to a population center, plug in to discharge. Repeat.

Though a smaller array (just covering the deck of a current ship) could provide some boost - 25% isn&#x27;t nothing, though you need clear skies to net that, I suppose we could consider a system when the ship would make a journey more slowly, stopping to charge for four days, sailing for one (though I assume drifting means you can&#x27;t really &quot;stop&quot; entirely so that&#x27;s not entirely practical).

If your average solar array gives 2.5MW per hectare then 15MW would require 6 x 100m x 100m to run, or a beam of 150m for a 400m long vessel (eg Evergreen G-class.)That’s only ~4x wider than the current big classes of ship. Maybe we will see twin hulls with a solar field slung in between?The downside of course is you can no longer romantically sail by starlight (or at least, technically, by the starlight of non-Sol stars.)

You&#x27;d need big batteries in the port to act as a buffer and enough energy to charge those in between when no ships are docked. But the ship would be there for quite some time (up to a day or even more). So a few tens&#x2F;hundreds mw of power would go a long way.You&#x27;d probably want to use a mix of local wind&#x2F;solar power and a grid connection. Of course, harbors usually already have lots of infrastructure to power heavy industry (steel, refineries, etc.) and transport (e.g. rail). This just adds to that.There are also other solutions including using container batteries and simply swapping in fresh ones. Which especially in a container harbor shouldn&#x27;t be that big of a deal.

Heavy oil is almost a waste byproduct of oil refinery, could be found anywhere and quite cheap: 500$ per tonne, 500$ per 40GJ of energy.Pretty sure electric ships are not coming anywhere near long haul shipping. However for anything close to shore - it&#x27;s a real future: tugboats, bunkers, tourist boats etc.

Somehow I&#x27;d imagine that you could have container size and shape batteries and maybe even stop more often in ports to swap them out using existing crain mechanisms

2.7GWh &#x2F; 24h ~= 100MW. That&#x27;s SMR territory per ship, or a proper nuclear power plant if a few of them charge at the same time from empty to full, assuming they aren&#x27;t all empty at the same time...

Charging big battery takes the same amount of time as charging small battery if charger&#x27;s power is proportionally larger. E.g. charging Tesla at Supercharger takes same amount of time as charging phone using fastest phone charger.

They spend like a day at port so there is a bit of time to load. The logistics of getting the power to the port gonna be harder, as it&#x27;s literally hundreds of megawatts to load it at reasonable rate

Stick the batteries in containers and you just swap them and load them whenever it is convenient.

I think another problem is how fast you will be able to charge such a huge battery and how expensive such ship battery charger will be and if you expect to have such charger at most ports (ideally for every docked ship). Will you even need a power plant at every port?

The upper weight limit for both 20ft and 40ft shipping containers is around 28,300 kg. Since SodiumLion batteries in containers will be weight limited, it makes sense to use 20ft shipping containers. One container can probably store around 3MWh of energy. For a 2700nm trip at 15 knots with 15MW of power usage, you need 2700Mwh divided by 3MWh per container gives us 900 20 ft shipping containers (TEU) for the battery.OTOH if we look at popular shorter range routes like within Asia or Europe the calculation looks a lot more favorable.

The main obstacle here is the energy density of those is much lower. We&#x27;re talking 20-30wh&#x2F;kg. So you would need about 7-8x more mass compared to a 170wh&#x2F;kg battery. For ships like this (capable of 5000km), the tanks would take up most of the ship with barely any space for useful load.Otherwise, it&#x27;s not a bad idea as you could pump the pre-charged fluids in&#x2F;out and even ship the fluid around with tankers; which opens up the possibility of fueling at sea. Spills would be bad. But probably better than oil as the toxic fluids dilute more easily. But it would still be a bad day for marine life. It might work for shorter ranges.

The one technology that I thought might work really well here is flow batteries. You need a couple of sets of tanks, but then you can do charging by pumping out the old electrolyte and pumping in charged electrolyte. But these seem to have stagnated, possibly because they&#x27;re dependent on expensive short lived membranes.I wonder if there&#x27;s significant scope for offsetting electricity consumption by adding deck renewables. Not for container ships, but maybe for tankers .. which are only needed because of fossil fuel consumption elsewhere. Hmm.

&gt; Even the charging costs for 1GWh is absurdly high compared to Heavy Fuel Oil. An orders of magnitude more expensive.Burning 250 tons of oil to get 1GWh of energy releases around 800 tons of CO2. 
Let&#x27;s assume a $100 CO2 tax. We want to prevent the worst of global warming, right? That would add ~25% to the price of oil.There is likely to be an oversupply of renewable (solar) energy less than 5 years from now.So I wouldn&#x27;t be so sure about that 100 year prediction.

You forget that fuel is really expensive as well. And per gwh, electricity can be quite affordable if you don&#x27;t do something as silly as pay grid prices for it. The mwh price is 80–90$, so 3 gwh (3000mwh) would be about 240K $. That&#x27;s a lot of money. But filling up the tank of container ship is actually more expensive. Something like 5000 tons of fuel would be what you need. At 500$ per ton, you are looking at 2.5M $ in fuel.Sourcing the electricity cheaper than that should be possible. E.g. wind and solar are closer to 20-30$&#x2F;mwh.The main issue is harbor infrastructure and battery production and scaling this. But from a cost point of view, sacrificing 20% cargo for an order of magnitude reduction in fuel cost is going to be very tempting.&gt; Transoceanic battery-powered cargo vessels are probably 100 years away - fusion will arrive first.Or 3 years according to CATL. One of you is probably a few years off. I personally think 3 years is a bit ambitious. But ten years sounds like we might see some proof of concept at least. I have a hunch that CATL is going to be very eager to deliver such a proof of concept.

What you are suggesting in the best case is completely uncompetitive with current ships both in terms of weight and cost. Even the charging costs for 1GWh is absurdly high compared to Heavy Fuel Oil. An orders of magnitude more expensive.Not to mention dedicating 15-20% of deadweight tonnage (and a higher percentage, maybe 30-40% of its gross tonnage) would make a ship instantly uneconomical, especially as the batteries must be laid along the keel for stability, meaning the ship loses the ability to carry many cargoes.What&#x27;s possible in the medium term are Heavy Fuel Oil&#x2F;Electric hybrids that use battery power in regulated Emission Control Areas instead of Low Sulfur Marine Fuel Oils or Diesel, and using HFO in blue waters and to charge batteries.Transoceanic battery-powered cargo vessels are probably 100 years away - fusion will arrive first.

If deployed with hybrid sails [1] this could be even more competitive to Bunker fuel for bulk&#x2F;container carriers and even RoRo car carriers.IMHO a hybrid approach would achieve similar to superior perfomance to the current state viz a viz cost&#x2F;perfomance and enviromental impact.Additionally as has been deployed for some longhaul trucks battery swaps can also cut down on the time to redeploy after offloading the cargo.[1] <a href="https:&#x2F;&#x2F;gcaptain.com&#x2F;berge-bulk-launches-worlds-most-powerful-sailing-cargo-ship&#x2F;" rel="nofollow">https:&#x2F;&#x2F;gcaptain.com&#x2F;berge-bulk-launches-worlds-most-powerfu...</a>

Round trip efficiency would be very poor, looks like thermal storage is around 75% efficient for the heat then the heat engine (turbine) maxes out around 45% so maybe round trip 33% efficiency if you lucky.So that gives you around twice the wh&#x2F;kg but you must keep the heat energy for the entire voyage which is constantly being lost once the onboard storage is heated up. Not sure what that look like I imagine it would be difficult to keep lithium hydride at 680C very efficiently or safely in an ocean going vessel for any length of time.

&gt; If you assume 170 wh&#x2F;kgI&#x27;ve wondered if thermal storage might be superior. Lower round trip efficiency if one uses resistive heating, but I think that would be ok.Lithium hydride, heated to melting, stores something like 4 MJ&#x2F;kg, more than 6x the specific energy of your assumption there (admittedly with loss on discharge due to the losses in the turbine.) If that is too expensive, graphite is another possibility, at even higher temperature.

If we could only complement that battery with a small nuclear reactor, then we&#x27;d be in business.
Come to think of it, shipping would be quite interesting for a SpaceX style disruption - there is a market for many many thousands of units - enough to actually get good at building them in a repeatable fashion.
Of course there are considerable engineering and political challenges, to put it mildly.

Here&#x27;s some back of the envelope math for batteries and ships:- Weight is less of a limitation than you would think. Ship size is measured in tonnage. 40K-60K is a medium sized cargo carrying ship. So lets assume a ship like that.- Battery weight calculations are going to be key. If you assume 170 wh&#x2F;kg, 6 tonnes of battery equals about 1 mwh of battery.- Energy usage of ships is speed dependent and it&#x27;s a non linear relationship. You can save a lot of energy by going a bit slower. Going about 15 knots, a ship like this might use 15mw of power.So the math becomes something like 6 x 15 = 90 tons of battery per hour. 5000km is about 2700 nautical miles (1 knot == 1 nautical mile&#x2F;hour). So, you need about 180 hours of battery. Or about 16200 tons for a total of 15mwh x 180 = 2.7gwh of energy. That&#x27;s a big battery.The real limitation here comes from the cost of the batteries, which is dropping fast with sodium ion. The reason CATL is bringing this up is because they&#x27;ve been doing similar math with some informed $&#x2F;kwh math. If they can get it down to around 20$&#x2F;kwh, a mwh would cost 20K, and a gwh would cost 20M. So the battery would cost 54M$.The key here is that this is still assuming 15knots. Energy usage might drop considerably if you drop it to 10 knots or even lower. You might only need 7200 tons of battery at those speeds.The ship can handle the weight either way, though you are sacrificing useful load of course. The real constraints here are cost and speed. You pay a fat premium for a fast ship. Of course ships this size aren&#x27;t cheap. A few tens of millions is normal. And they burn through many millions worth of fuel per year too. So, even though that amount of battery is expensive, the math might actually work out to these ships being cheap enough to operate that they&#x27;d earn back their battery.You&#x27;d have to be pretty bullish about cost and performance of batteries. But CATL clearly feels that way. They have several battery chemistries at their disposal with higher densities (and cost). Over time, batteries might get cheaper and more dense. Ship designs might be optimized for batteries (e.g. structural hulls with battery). There&#x27;s a lot of wiggle room here. But it&#x27;s not an impossible proposition.

Why would you bother with the complexity of containerized nuclear reactors when you have containerized batteries that can easily be loaded&#x2F;unloaded by standard port facilities?

What about the scenario where you just want to refuel? Shuffling containers around just to get the batteries out seems suboptimal.

Okay based on your calculation, here&#x27;s a neat way to do this.The battery capacity you have calculated needs about 500 shipping containers.A large shipping vessel carries 24000 container. So make the batteries containerized, and easy to load&#x2F;unload.You could imagine pretty fast charging like this, and at some point in the near future using the same infrastructure with containerized nuclear reactors.

Massive battery banks at the ports. Charging batteries off of batteries can yield incredibly fast charge times.

Thinking of charging is also interesting. What is the power requirement for that? If they use 40MW under operation, it means they must charge faster unless they spend at least as long time charging. So that capacity requirement can get quite high.

Battery energy density is way behind that of bunker fuel, it’s just that cargo ships (at least as far as some googling suggests), have fuel capacity far in excess of what is required for a 5000km range.

I am really surprised that the mass and volume requirement for batteries are within the same order of magnitude as for bunker fuel for this task. I thought batteries were still lagging far behind!Is bunker fuel energy density just that bad or is it something else? A 50kg tank of diesel can easily outperform a 200kg pack of batteries in an ev.

No need do charge in-situ, the ships (and ports) already transfer several times the battery volume and weight on berthing quickly . The battery systems could be designed to leverage that .Fire hazards are there for any fuel, Safety systems evolve to handle them. The environmental impact would be more localized than an oil spill.

Just make the battery banks container sized and swap them out with fresh ones while doing the main cargo. Then service and charge the old ones.

A quick googling suggests that unloading such a vessel takes at least a couple of days, more likely 3-4.Assuming two days available to charge the vessel, you&#x27;d need about 100MW continuous. Not trivial, but doable.As far as battery fires go, sure, but a) there are already a lot of electric ferries in service so designing safe maritime battery packs isn&#x27;t a new challenge and b) the alternative isn&#x27;t exactly risk free either; we&#x27;ve seen plenty of oil spills from ships.

Sodium batteries have substantially reduced thermal runaway risk compared to lithium. Worst case, the ship sinks during a fire and the batteries are flooded. Charging infra is likely similar to existing EV ferry charging infra. Ship pulls into the berth and starts soaking the battery storage up to 1C up until departure. Could probably use a heat exchange and raw water available for battery cooling to maximize charge current curve, actively cooling the battery storage during charging.<a href="https:&#x2F;&#x2F;www.phmsa.dot.gov&#x2F;sites&#x2F;phmsa.dot.gov&#x2F;files&#x2F;2023-04&#x2F;DOT-SIB-Testing-Report-Web-Version.pdf" rel="nofollow">https:&#x2F;&#x2F;www.phmsa.dot.gov&#x2F;sites&#x2F;phmsa.dot.gov&#x2F;files&#x2F;2023-04&#x2F;...</a><a href="https:&#x2F;&#x2F;old.reddit.com&#x2F;r&#x2F;electricvehicles&#x2F;comments&#x2F;1m8wlou&#x2F;electric_ferry_charger&#x2F;" rel="nofollow">https:&#x2F;&#x2F;old.reddit.com&#x2F;r&#x2F;electricvehicles&#x2F;comments&#x2F;1m8wlou&#x2F;e...</a>

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

Not really, kerosene is pretty close to heavy fuel oil on density.Planes run on kerosene because it&#x27;s universal enough, hard to run them on heavy fuel, and there is issue with high emission of the HFO over population centers which isn&#x27;t as much of a problem in middle of sea

The biggest problem with Electric is the battery weight, so it makes sense.Ships deliberately use cheaper, less energy dense petroleum products (heavy fuel oil), for pretty much the inverse reasons why airplanes use kerosene.

OK, I did some calculations based on:* a 5,000 km electric range.
* 40MW continuous power requirement for a 21.5 knot cruise speed[1] for a 14000 teu container vessel: 
* the size and weight capacity for the batteries being the same as the fuel capacity for a 14000 teu container vessel (taking the upper figure from [2])
* the battery pack having similar gravimetric (weight) and volumetric(size) energy density as this a modern Chinese NMC EV pack[3]The short version is that the battery vessel would require about 25,000 tonnes of batteries for a 5,000km range under those assumptions, which compares to the current fuel capacity of approximately 13,000 tonnes. Volumetrically, it&#x27;s even closer - about 17,000 cubic metres, compared to about 13,000 for the bunker fuel.Furthermore, it&#x27;s worth considering just how much cargo the ship carries. One teu corresponds to about 33 cubic metres of cargo space (not counting the space taken up by the walls of the container), so the ship can carry about 462,000 cubic metres of cargo. So the additional space required to carry an additional 3,500-odd cubic metres of batteries corresponds to only about 0.8% of the ship&#x27;s total cargo-carrying capacity.I was surprised at just how doable this is, to be honest. What threw me is just how much bunker fuel ships can carry; if I&#x27;m doing the sums right, a ship like this can carry enough fuel to circumnavigate the globe a couple of times over. It may well make economic sense but it&#x27;s not really necessary to have that kind of range to operate the ship safely.[1]<a href="https:&#x2F;&#x2F;www.man-es.com&#x2F;docs&#x2F;default-source&#x2F;marine&#x2F;tools&#x2F;propulsion-of-14-000-teu-new-panamax-container-vessel.pdf?sfvrsn=58b2c2_14" rel="nofollow">https:&#x2F;&#x2F;www.man-es.com&#x2F;docs&#x2F;default-source&#x2F;marine&#x2F;tools&#x2F;prop...</a>
[2]<a href="https:&#x2F;&#x2F;www.freightwaves.com&#x2F;news&#x2F;how-many-gallons-of-fuel-does-a-container-ship-carry" rel="nofollow">https:&#x2F;&#x2F;www.freightwaves.com&#x2F;news&#x2F;how-many-gallons-of-fuel-d...</a>
[3]<a href="https:&#x2F;&#x2F;www.batterydesign.net&#x2F;zeekr-140kwh-catl-qilin&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.batterydesign.net&#x2F;zeekr-140kwh-catl-qilin&#x2F;</a>

Just to put the market into perspective, the UK was looking to build an undersea cable to push power from Morocco but canceled it [1]. That cable would have provided somewhere around 8% of the power to the UK and the whole project was slated to cost 25bn pounds (~$33b USD). Imagine sahara solar shipping could provide that but also supply (cheaper) to Spain, Italy, etc. As the tech gets better and cheaper the Americas could become customers too. Suddenly Timbuktu becoming an energy hub for the world doesn&#x27;t sound as crazy as, well, it sounds.[1] <a href="https:&#x2F;&#x2F;apnews.com&#x2F;article&#x2F;uk-morocco-renewable-energy-xlinks-8ec20cbdf7632508003fae54a751895c" rel="nofollow">https:&#x2F;&#x2F;apnews.com&#x2F;article&#x2F;uk-morocco-renewable-energy-xlink...</a>

AWS Snowmobile exists , I wouldn’t call filling a truck (or a plane) with hard disks insane .

That&#x27;s both amazing and hilarious just like filling a plane with hard drives is both insanely effective and just plain insane.

I did some fast back of the napkin math on the idea of sahara solar + electrified shipping + sodium ion batteries. A lot depends on the, as yet, fully disclosed pricing of sodium ion batteries but the trend in pricing, and capacity, is clear and the price point may have already happened to make this viable. One thing is clear though, even if my napkin math was massively optimistic and it isn&#x27;t economically feasible now it will be shortly and at that point energy production around the world is potentially disrupted. Ships can pull in and feed the grid directly or offload containers and onload empty ones to make the trip back for cheap, clean, renewable power. It is looking more and more viable to ship electrons like we do for oil and that is a major game-changer.

Those small islands also don’t have any infrastructure to recharge such ships. The small ones often struggle even to serve their own needs.

East Asia has extensive coastal medium-distance trade. There are so many islands and island nations. That&#x27;s oceanic trade, but not transatlantic or trans-pacific long hauls.

Fully autonomous cargo shipping is coming with the next update.

If it were Elon Musk saying it, I’d agree, but this is CATL. They actually do the work.

I guess I want to know &quot;oceanic&quot; means in this instance. Is that just going out into the ocean a short distance? They mention the &quot;Yangtze River Three Gorges 1&quot; river cruise ship as an example. This thing has a range of like 100km. It seems we are far away from making true oceanic crossings of any long distance and I doubt that is coming by 2028.

Hybrid propulsion is already a thing in the marine world (often in navy&#x2F;military designs):* <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Combined_diesel–electric_and_gas" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Combined_diesel–electric_and_g...</a>* <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Combined_diesel–electric_and_diesel" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Combined_diesel–electric_and_d...</a>* <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Integrated_electric_propulsion" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Integrated_electric_propulsion</a>

I found your reply unnecessarily snarky. The possibility I&#x27;l pondering would be to have a facility in deep ocean, far away from any countries coastline, but near shipping lanes.

&gt; I wonder if some kind of big floating energy station could be a thingCongratulations, you have just re-invented offshore (floating) wind turbines. <a href="https:&#x2F;&#x2F;duckduckgo.com&#x2F;?t=ftsa&amp;q=floating+wind+turbines+&amp;ia=web" rel="nofollow">https:&#x2F;&#x2F;duckduckgo.com&#x2F;?t=ftsa&amp;q=floating+wind+turbines+&amp;ia=...</a>&gt; I guess you don&#x27;t have to pay anyone for the space or worry about too many regulations etc.I&#x27;m ammused you think offshore energy is lawless. It&#x27;s the same assumption that had the entire maritime community laughing at the clowns behind &#x27;Seasteding&quot; and the amusing MS Satoshi &#x27;cryptoship&#x27;.

I like your idea. We can now generate substantial amount of power from floating wind turbines. Coupled with floating batteries (ie on cargo ships) we perhaps build floating charging stations along major shipping routes. There is no need for nuclear or to only charge at ports. Would it work?

Since there is a lot of space out there in the ocean I wonder if some kind of big floating energy station could be a thing, using middle of the ocean wind, tidal or solar. I guess you don&#x27;t have to pay anyone for the space or worry about too many regulations etc.

This is overly optimistic.If you expect _oceanic_ ships in 3 year, you need to start building infrastructure today, in multiple ports.If you need to build those infrastructure today, you need to have something standardize.otoh, if all you want are just some prototypes, we have them today already..

Ships sail at the cost of static resistance in water. Larger ships are more efficient, once buoyant. There is a New Scientist story about a guy on guard duty moving a moored navy boat by leaning on it, for a long period of time.TL;DR marine is the one niche where &quot;we had to make it a lot bigger to hold the batteries&quot; isn&#x27;t actually a big deal. If you do this the right way, you still have heaps of volume for cargo, and solar cells on the hold covers.

Actually thinking about it some more why not park a couple of dozen older cargo ships along major shipping route. Equip them with wind turbines and batteries in shipping containers. Now the actual cargo ships passing by can stop for a few hours, plug in and charge. Use sodium ion batteries that can support thousands of cycles. Even use regular fuel as a backup in the charging ships. You can build and maintain anywhere and then haul them to the right location.

Clusters of floating wind turbines each with their own battery storage might be useful here. I imagine along strategic (ie major) shipping channels. Would it pencil out? I have no idea.

The US with its sunk cost and political power base in fossil fuels is losing the innovators dilemma at a large scale here.

Your math seem to work out, but I don&#x27;t like the incoherent use if energy units.60 MWh per what? Per hour? thats just 60 MW continuous POWER or 1440 MWh ENERGY per day.

Unfortunately, it&#x27;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&#x27;s not factoring in the solar panels getting covered in salt over time and losing efficiency. Plus preventing the ship from actually loading &#x2F; unloading cargo efficiently.It&#x27;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).

All resources are &quot;scarce&quot; at very low price points, below which most nations are unable or unwilling to extract them.Lithium, rare earth metals, and a bunch of others are only &quot;scarce&quot; because right now China is the only country willing to put up with the pollution levels that the cheap, dirty version of their extraction produces.Everything can be produced cleanly, safely, etc... but that comes at a price.It&#x27;s like when employers complain that &quot;nobody wants to work&quot;. That needs to be translated to &quot;nobody wants to work for the low wages I&#x27;m willing to pay&quot;.

By the time we get around to building these it would likely be sodium ion anyway

Maybe not scarce in an absolute sense but what about whether there is a spare million tons lying around to make ship batteries?

Lithium is not scarce, and not a limiting factor for scaling up batteries.There&#x27;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&#x27;t worry about lithium use!

Plenty of engineers exist in sailing who know all that and have studied this. Boeing brings nothing new if they get in. Well other than perhaps dollars, but that isn&#x27;t the problem for the most part.

Smaller boats sure, but ocean going cargo vessels? There are some serious challenges!Try to approximate the area needed to generate e.g. 50MW propulsion. It would be measured in hectares.

No, but with wind it&#x27;s possible. Either vertical windmills or sails with modern signal processing.Honestly DJI and Boeing should get into this business. A boat&#x27;s sail basically a plane&#x27;s wing, aerodynamically speaking. They share a lot of similarities with endurance gliders.

&gt; Not to mention that a container ship’s deck is typically completely covered with, well, containers.I guess in theory that could be solved either with huge removable panels around the containers (to be &quot;put aside&quot; somewhere during the loading operations), or placing containers with solar panels (and ways to deliver the energy to the ship) on the outer sides of the cargo.Actually, maybe the batteries themselves could be loaded as containers on the sides of the cargo, with solar panels on them; that might increase the risk for the cargo if some catch fire, thoughBut, I guess it wouldn&#x27;t be worthwhile.

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.

Yes, but it would move very slowly compared to current freight ships, think an order of magnitude lower average speed. (You can compromise on the freight features to get some more speed of course, but it&#x27;s still going to be slower unless you do something dramatic like fly a huge PV array as a kite or something)Besides PV, there&#x27;s a long history of wind powered ships of course.

There are examples of solar electric catamarans - but they are much smaller than a cargo vessel. It&#x27;s not nothing, but we&#x27;re some ways away.I wouldn&#x27;t underestimate what creative and dedicated engineers can accomplish.

Is it possible for ocean vessel to generate from sun panels as much as needed for moving? I would suggest vessels does not need scarce Lithium, it is too needed for some other uses.

Electrifying ferries is great, but this particular one has a run time of 20 minutes (and a charge time of 10 minutes). I get a totally different vibe from &#x27;oceanic ship&#x27; than a 20 minute ferry ride.Near me, we now have a hybrid ferry, no charging infrastructure, but it still uses much less fuel than before it was refit, so that&#x27;s cool too. It&#x27;s bigger than the one you linked and sails on a longer route: 2,499 passengers, 202 vehicles, typically serves an 8.6 mile route.<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;MV_Wenatchee" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;MV_Wenatchee</a>

Yeah, the oceanic part is the issue. Going between two close points, at least one of which has electricity, is easy.

There are multiple electric ferries already in operation:<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;MV_Ampere" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;MV_Ampere</a>They are quite impressive but they are still very far away from your average ocean going cargo vessel.

Energy density doesn&#x27;t seem to matter much in boats. Massive ships carry astronomical amounts of cargo.

The top upvoted comment on this post suggests it&#x27;s less than double.

Depends on the current fuel-to-payload ratio of the diesel ships. If it&#x27;s 3% and batteries would push it to 10%, it&#x27;s not a huge problem. But if it&#x27;s 15% and batteries would push it to 50% you&#x27;re losing a lot of capacity.

Right, but batteries are still improving quickly. They won&#x27;t stay where they currently are.

... and energy densities of batteries will _stay_ well below that of tanks of hydrocarbons, as <a href="https:&#x2F;&#x2F;web.archive.org&#x2F;web&#x2F;20130204210054&#x2F;http:&#x2F;&#x2F;h30565.www3.hp.com&#x2F;t5&#x2F;Feature-Articles&#x2F;How-Good-Can-Batteries-Get&#x2F;ba-p&#x2F;994" rel="nofollow">https:&#x2F;&#x2F;web.archive.org&#x2F;web&#x2F;20130204210054&#x2F;http:&#x2F;&#x2F;h30565.www...</a> explains.

I am very skeptical. Battery tech is still far away from the energy density of diesel fuel. How far could an electric ship go and what could it carry?

If we ever end up doing that it would mean terrible things for the state of our regulatory landscape.A completely optimized high capacity cargo rail line can move 500 rail cars per hour. That&#x27;s 1000 FEUs if we double stack containers. A lithium battery system in a FEU has around 2 MWh of storage. So that rail line has 2 GW transmission capacity if we saturate it with batteries - the same as a single high voltage transmission line. Being unable to build one of those in parallel to the rail line would be extremely sad.Note that 500 rail cars per hour is actually an impressive feat of logistics. A normal rail yard at a port would be very happy with a sustained rate of 200 rail cars per hour, and will frequently drop below that.

It would be amazing if they could leverage the container system, but instead of goods, there&#x27;d be battery containers they could just plug in to the ship. You could even charge a battery container somewhere and bring it in by (electrified) rail.

Russia is operating nuclear civil vessels (icebreakers) since 1957

French nuclear submarines run on 7% enriched fuel, so it&#x27;s certainly possible to build military submarines that don&#x27;t need HEU.

There are nuclear icebreakers.Nuclear powered non military ships do exist, it just not economically feasible .

US nuclear submarines consume highly-enriched uranium, that&#x27;s nearly as (and sometimes more) pure as the weapons-grade version. That doesn&#x27;t mean oceanic reactors aren&#x27;t possible, it just means that military subs are a bad example.

Yep, was just lookin up their recent news on this: <a href="https:&#x2F;&#x2F;www.allseas.com&#x2F;en&#x2F;who-we-are&#x2F;news-and-media&#x2F;allseas-smr-technology-offers-major-strategic-opportunities-netherlands" rel="nofollow">https:&#x2F;&#x2F;www.allseas.com&#x2F;en&#x2F;who-we-are&#x2F;news-and-media&#x2F;allseas...</a>

While perhaps not practical for oceanic shipping as is, it&#x27;s a fun exercise to demonstrate the energy density of nuclear power.

We already have electric oceanic ships. They’re called nuclear submarines.Allseas is putting the reactors on their vessels as well iirc.

&gt; In a perfect world however... endless cooling water unless they&#x27;re in some shallow harbor. Would be the perfect application.Still not, because all it takes is one thing going Seriously Fucking Wrong on another ship and boom, you got yourself a nuclear disaster. Just look at the Francis Scott Key Bridge and imagine that that ship hadn&#x27;t hit a bridge support but a nuclear powered vessel.Nuclear powered ships only make sense for ships operating in places where there is no other ship in sight for hundreds of miles (i.e. icebreakers) or for military ships that can and will shoot and sink anything with the potential of becoming a threat.

Not even the Russians could decommission their nuclear subs properly. I&#x27;m relatively sure that random semi-shading shipping companies wouldn&#x27;t either.In a perfect world however... endless cooling water unless they&#x27;re in some shallow harbor. Would be the perfect application.

The germans tried that in the 60s see <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Otto_Hahn_(ship)" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Otto_Hahn_(ship)</a>. 
It was uneconomical. 
You need specialized engineers for that, you need special permissions for ports and the important canals are off limits due to risk.

But an extremely expensive crew to run it coupled with extremely high CAPEX.Even navies are moving away from nuclear power due to how expensive it is.

For a vessel the size of a container ship, mounting an SMR (Small Modular Reactor) directly to power it would likely result in less energy loss.

<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Sevmorput" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Sevmorput</a>

certainly there exist nuclear ships with enough power but I fail to see how you would feasibly tug a train of containerships

I wonder if nuclear containerships can be developed and have enough power to pull a train of containerships.

I guess if it works for cars then boats should too

Pods are used primarily for manoverability. This allows Cruise ships to get in and out of ports with a minimum of assistance (none at all, if conditions permit). This is important because they are entering and leaving ports every day or two. It also makes sense as the hotel loads on these floating skyscrapers is similar to the propulsion loads so having combined main engines and generators gives other advantages.Ocean going container vessels on the other hand use massive direct drive two stroke diesel engines (usually they only have a single engine). They have no gearbox. The only way to go-astern is to literally start the engine in reverse. This can only be done up to a limited speed, otherwise the windmilling effect of the water passing through the prop would overpower the starting air.Suffice to say, I&#x27;d put a long bet on the overwhelming majority of containerships being powered by internal combustion engines in 30 years time. If we get our act together we might have come up with an alternative &#x2F; synthetic fuel by then but I wouldn&#x27;t hold my breath.

Regenerative braking for boats would be a complete waste.Unless you have a large sail to generate thrust to spin the propeller...

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 &#x27;pods&#x27; 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.

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.

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.

Solar on board of cargo vessels is a pipe dream, as is &#x27;wave based generation&#x27;.

Wind, large surface area for solarAlso wave based generators that could also act as dampers&#x2F;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.

Cars have regenerative breaking which is a help in urban areas.Ships tend to go not change course nearly as much on a several day journey. I guess a propellor could run in reverse for regenerative breaking, but it wouldn’t help much.

You really should try to read up to at least the second sentence of a comment before hitting reply.

Sorry this makes zero sense. The low price of shipping comes from the huge size of ships. All these 100% sailing ventures are just so someone can sell you gourmet coffee with a nice story at outrageous prices

I searched a little bit and found these numbers for t-shirts in a 20 foot container:- Shipping container from China to the US: $3000-$9000 (tariffs?)- Number of t-shirts per container: 35000How much heavier are jeans than t-shirts? 10 times? That would mean an increase of $2.50 if container shipping costs double.

I wonder how much the jeans would cost if the price of shipping (i.e. the cost per container ocean mile) were to double.

Sails [0] [1] [2] are obviously more sustainable than the gigantic industry needed around batteries this size. That&#x27;d of course massively increase the cost of shipping and suddenly producing most things locally would make more economical sense. Bye bye £2 jeans from Shein.[0] <a href="https:&#x2F;&#x2F;www.towt.eu&#x2F;en&#x2F;home&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.towt.eu&#x2F;en&#x2F;home&#x2F;</a>[1] <a href="https:&#x2F;&#x2F;www.neoline.eu&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.neoline.eu&#x2F;</a>[2] <a href="https:&#x2F;&#x2F;graindesail.com&#x2F;fr&#x2F;voilier-cargo-grain-de-sail-3&#x2F;" rel="nofollow">https:&#x2F;&#x2F;graindesail.com&#x2F;fr&#x2F;voilier-cargo-grain-de-sail-3&#x2F;</a>