Here's some back of the envelope math for batteries and ships:<p>- 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.<p>- Battery weight calculations are going to be key. If you assume 170 wh/kg, 6 tonnes of battery equals about 1 mwh of battery.<p>- Energy usage of ships is speed dependent and it'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.<p>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/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's a big battery.<p>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've been doing similar math with some informed $/kwh math. If they can get it down to around 20$/kwh, a mwh would cost 20K, and a gwh would cost 20M. So the battery would cost 54M$.<p>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.<p>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'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'd earn back their battery.<p>You'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's a lot of wiggle room here. But it's not an impossible proposition.
Those are some big numbers. It makes me think of a crazy thought experiment:<p>How many MW could a container ship carry by literally shipping energy stored in batteries?<p>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.
That'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.<p>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 "energy cargo" 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 "tanker":<p><a href="https://power-x.jp/en/newsroom/Introducing-the-world%E2%80%99s-first-battery-tankerX" rel="nofollow">https://power-x.jp/en/newsroom/Introducing-the-world%E2%80%9...</a><p>I think there are some startups working on cargo train "tankers" in the US too.<p>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.
Ha, that's like the quote: "Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway."
Panamax ship is 5000 teu (twenty foot shipping container equivalent)<p>I think you get about 4 MWh per TEU ( based on my 12V 100Ah battery)<p>so about 20 GWh
At 170Wh per kg (and ignoring the weight of the containers and any safety considerations), 20GWh of lithium battery would weigh 120,000 tons. This is a lot more than a typical Panamax DWT of 60,000 tons, which also needs to include the ship's fuel, provisions, crew, etc.
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 <i>Evergreen</i> G-class.)<p>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?<p>The downside of course is you can no longer romantically sail by starlight (or at least, technically, by the starlight of non-Sol stars.)
Though a smaller array (just covering the deck of a current ship) could provide some boost - 25% isn'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't really "stop" entirely so that's not entirely practical).
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?
You'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/hundreds mw of power would go a long way.<p>You'd probably want to use a mix of local wind/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.<p>There are also other solutions including using container batteries and simply swapping in fresh ones. Which especially in a container harbor shouldn'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.<p>Pretty sure electric ships are not coming anywhere near long haul shipping. However for anything close to shore - it's a real future: tugboats, bunkers, tourist boats etc.
Somehow I'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 / 24h ~= 100MW. That'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't all empty at the same time...
That kind of load is roughly comparable to what a modern rail network consumes. We're talking heavy transport here, of course it consumes power. The London underground consumes something like 1.2twh per year. Peak loads of around 150 mw. It's very comparable.<p>Harbors are already very large consumers of power. Sure, this adds to that demand but if you think about all the cranes, heavy industry, refineries, freight trains, etc. you can get to a few hundred mw easily. Adding more would definitely need planning. But it's not so dramatic. This just sounds like a good reason to invest in power generation.
Charging big battery takes the same amount of time as charging small battery if charger's power is proportionally larger. E.g. charging Tesla at Supercharger takes same amount of time as charging phone using fastest phone charger.
I don't think you can just take tesla supercharger and scale it that easily to use in ships. You have to think how thick charging cables you have, how many of those you need to connect to your ship, how heavy they are, how long they are, how much heat the generate. Remember such battery would be many orders of magnitude bigger than in tesla. Tesla charger cable is many times order thicker than your usb charging cable. Now imagine many times order thicker ship charging cable and how heavy it is, how less elastic it is, how much heat generates, how much isolating cover needs (for heat, protection, magnetic field).
Yes, this is true. Realistically, a "charging station" for a ship this size would have a large pierside structure to transform/regulate, and a very large cable array that would probably be moved to the ship via a crane. The connectors would almost certainly require manual fitup and the operation would require several personnel.<p>(Similarly, refueling a ship is substantially more complicated than refueling an automobile.)<p>Maritime engineers and workers can get this job done.
Scaling won't be hard - worst case you could just install 1000 250 kilowatt superchargers on the dockside, plug them all in and get 250 megawatts.<p>Obviously there are better solutions, but that solution demonstrates feasibility with no further engineering work required.
There already exist purpose-built chargers for electric ships. See, for example, <a href="https://www.stemmann.com/en/products/charging_systems/ferrycharger" rel="nofollow">https://www.stemmann.com/en/products/charging_systems/ferryc...</a><p>To support a 48 hour recharge of the battery hypothesized upthread, you would only need to scale up this system by about 10x. Or attach 10 along the length of the ship. Or some combination of those options.<p>This is a non-problem.<p>Edit: Excuse me, but I misread the brochure. The existing system need be only scaled up by a factor of <i>2.5x</i> to recharge a container ship in 48 hours.
You could increase the battery pack voltage and/or charge several packs in parallel. Why not have 20 charging cables. Shouldn't be a problem for a ship. Would of course be fairly inconvient for a car.
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'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.
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're dependent on expensive short lived membranes.<p>I wonder if there'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.
The main obstacle here is the energy density of those is much lower. We're talking 20-30wh/kg. So you would need about 7-8x more mass compared to a 170wh/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.<p>Otherwise, it's not a bad idea as you could pump the pre-charged fluids in/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 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.<p>OTOH if we look at popular shorter range routes like within Asia or Europe the calculation looks a lot more favorable.
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.<p>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.<p>What's possible in the medium term are Heavy Fuel Oil/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.<p>Transoceanic battery-powered cargo vessels are probably 100 years away - fusion will arrive first.
> Even the charging costs for 1GWh is absurdly high compared to Heavy Fuel Oil. An orders of magnitude more expensive.<p>Burning 250 tons of oil to get 1GWh of energy releases around 800 tons of CO2.
Let'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.<p>There is likely to be an oversupply of renewable (solar) energy less than 5 years from now.<p>So I wouldn't be so sure about that 100 year prediction.
Even under the EU Emissions Trading System (ETS), where shipping companies already must buy allowances for CO2 emissions from large vessels calling at EU ports, costing roughly €80-€90 per tonne of CO2 emitted, batteries aren't remotely competitive with HFO/LSMFO.<p>Even if the electricity was free, the cost (both CAPEX and in mass/volume) is not close. We need an improvement in mass energy density and volumetric energy density of 200-1,000% and a complete redesign of all shipping and ports to migrate to battery transoceanic shipping.<p>SMRs, renewably cracked hydrocarbons, and fusion will all be mainstream beforehand.<p>Once again, this is one of those areas where HN commenters believe they can understand a complex industry based on Wikipedia-level stats.
> Once again, this is one of those areas where HN commenters believe they can understand a complex industry based on Wikipedia-level stats.<p>Please elaborate your math here. I just outlined the cost of batteries, the cost of fuel, the cost of electricity. Is my math wrong? Because if it isn't, it's at least feasible. You seem to assume very different numbers here. Which I would argue are probably a combination of dated and wrong.<p>> SMRs, renewably cracked hydrocarbons, and fusion will all be mainstream beforehand.<p>We'll know in a few years how wrong you or I will be. I don't find your argumentation very persuasive though. You might be eating your proverbial hat by the 2040s. I'm betting somebody will manage to stuff a few gwh of battery in a ship by then. A shipment of 7-9K EVs at 50kwh each, pretty much gets you there. That's the capacity of some of the new ships that BYD uses for transporting their EVs around the world. 2000EVs is basically about 1 gwh of power.
Yes, your maths is off by roughly an order of magnitude because the starting assumptions are wrong.<p>> The mwh price is 80–90$, so 3 gwh (3000mwh) would be about 240K $<p>You’re effectively designing around ~3GWh for an ocean leg, but a large container vessel at 40–60MW continuous draw burns roughly 1–1.5GWh per day at sea.<p>A 20–30 day crossing needs on the order of 20–40GWh of shaft power, not 3GWh. 5,000t of HFO actually corresponds to ~50–60GWh of chemical energy and ~25–30GWh delivered to the propeller at realistic engine efficiencies.<p>> The mwh price is 80–90$<p>$80–90/MWh is a generation/LCOE number, which you're comparing to $500/t HFO delivered, stored, with global bunkering logistics already in place.<p>You're not accounting for the cost of delivering tens of GWh at hundreds of MW into a hull, in a tight port stay, via infrastructure that simply doesn’t exist. Even if you grant free electricity at the fence, the capex for multi-hundred-MW substations, converters, cabling, connectors, etc completely dominates.<p>> A shipment of 7-9K EVs at 50kwh each, pretty much gets you there. That's the capacity of some of the new ships that BYD uses for transporting their EVs around the world. 2000EVs is basically about 1 gwh of power.<p>2,000 EVs * 50kWh ≈ 100MWh. 9,000 EVs * 50kWh ≈ 450MWh. That’s still one to two orders of magnitude below what a long-range deep-sea vessel actually needs on a single leg.<p>> We'll know in a few years how wrong you or I will be.<p>Anyone in or close to the maritime industry knows now. Not even the most bullish consider economic transoceanic shipping by battery-powered vessels by the 2040s remotely possible. Realistically pure-battery transoceanic cargo ships will never happen, because other superior zero-carbon options will become viable long before batteries close the energy density and infrastructure gap.<p>We'll obviously see batteries in tugs, ferries, short-sea and hybrid ECA work become the standard much sooner.
You forget that fuel is really expensive as well. And per gwh, electricity can be quite affordable if you don't do something as silly as pay grid prices for it. The mwh price is 80–90$, so 3 gwh (3000mwh) would be about 240K $. That's a lot of money. But filling up the tank of container ship is actually more expensive. Something like 5000 tons of fuel would be what you need. At 500$ per ton, you are looking at 2.5M $ in fuel.<p>Sourcing the electricity cheaper than that should be possible. E.g. wind and solar are closer to 20-30$/mwh.<p>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.<p>> Transoceanic battery-powered cargo vessels are probably 100 years away - fusion will arrive first.<p>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.
As stated elsewhere, even if the electricity to charge was free, batteries won't be economically competitive with HFO/LSMFO in this century.<p>> 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.<p>No, it's not and this shows a profound misunderstanding of the maritime sector. Not to mention, it would be at least 20% of DWT and probably 40% of gross tonnage, and all at the most valuable (lowest/most-stable) part of the hull.<p>> Or 3 years according to CATL.<p>CATL make no such claim. They claim that they will be able to show electric ocean-going vessels, which there already are. They make no claims about transoceanic shipping, other than partnering with Maersk, which as stated above, will be for hybrid propulsion to avoid expensive low-sulfur fuels in ECAs and will be charged from HFO at sea.
If deployed with hybrid sails [1] this could be even more competitive to Bunker fuel for bulk/container carriers and even RoRo car carriers.<p>IMHO a hybrid approach would achieve similar to superior perfomance to the current state viz a viz cost/perfomance and enviromental impact.<p>Additionally as has been deployed for some longhaul trucks battery swaps can also cut down on the time to redeploy after offloading the cargo.<p>[1] <a href="https://gcaptain.com/berge-bulk-launches-worlds-most-powerful-sailing-cargo-ship/" rel="nofollow">https://gcaptain.com/berge-bulk-launches-worlds-most-powerfu...</a>
> If you assume 170 wh/kg<p>I've wondered if thermal storage might be superior. Lower round trip efficiency if one uses resistive heating, but I think that would be ok.<p>Lithium hydride, heated to melting, stores something like 4 MJ/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.
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.<p>So that gives you around twice the wh/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.
> looks like thermal storage is around 75% efficient for the hea<p>That seems unreasonably low. Thermal losses can be made arbitrarily low with insulation, and this is fairly large scale, so insulation can be thick and volume per surface area can be kept low.
Would love to see any data you have, what kind of storage tank on a ship could keep 680C lithium hydride insulated without significant losses for say a 30 day voyage?
We were talking about a 180 hour battery (7.5 days), not a 30 day battery.<p>But back of the envelope: 2.7 GWh of heat in LiH at 4 MJ/kg and 820 kg/m^3 is a sphere 9m in radius. If we put a 1m layer of microporous silica insulation (conductivity ~0.03 W/mK) this gives a thermal time constant of 300 days.
Sorry I was considering a standard container ship voyage at 30 days.<p>A 9m sphere of 1m thick Aerogel will probably cost above $500k just for the material.<p>Also lithium hydride itself reacts violently with water, not sure if you want to have a 9m radius 5 million pound sphere of it on a water vessel, this is the "safely" part.
I mean, can be kept high.
If we could only complement that battery with a small nuclear reactor, then we'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.
OK, I did some calculations based on:<p>* 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]<p>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's even closer - about 17,000 cubic metres, compared to about 13,000 for the bunker fuel.<p>Furthermore, it'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's total cargo-carrying capacity.<p>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'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's not really necessary to have that kind of range to operate the ship safely.<p>[1]<a href="https://www.man-es.com/docs/default-source/marine/tools/propulsion-of-14-000-teu-new-panamax-container-vessel.pdf?sfvrsn=58b2c2_14" rel="nofollow">https://www.man-es.com/docs/default-source/marine/tools/prop...</a>
[2]<a href="https://www.freightwaves.com/news/how-many-gallons-of-fuel-does-a-container-ship-carry" rel="nofollow">https://www.freightwaves.com/news/how-many-gallons-of-fuel-d...</a>
[3]<a href="https://www.batterydesign.net/zeekr-140kwh-catl-qilin/" rel="nofollow">https://www.batterydesign.net/zeekr-140kwh-catl-qilin/</a>
Okay based on your calculation, here's a neat way to do this.<p>The battery capacity you have calculated needs about 500 shipping containers.<p>A large shipping vessel carries 24000 container. So make the batteries containerized, and easy to load/unload.<p>You could imagine pretty fast charging like this, and at some point in the near future using the same infrastructure with containerized nuclear reactors.
Why would you bother with the complexity of containerized nuclear reactors when you have containerized batteries that can easily be loaded/unloaded by standard port facilities?
You can carry more cargo if you don't need all those batteries. If that difference makes economic sense is not yet known of course, as there are no containerized nuclear reactions that I know of.
> <i>as there are no containerized nuclear reactions that I know of.</i><p>Even if you built one, as some people have proposed designs, it doesn't get you nuclear reactors you can just stack up on a ship or something. Containerized reactors could be convenient for getting a reactor to a remote site where it's needed but once there you'll have to provide substantial shielding for it; usually the way this is meant to be done in these proposals is digging a big hole and/or putting up earthen berms around it. And those earthen berms will be subjected to a lot of neutron radiation, so you need a plan to deal with the site after you run this reactor for any substantial amount of time; the whole site will be radioactive.<p>There's really no getting around this, and most of the people pitching container-sized nuclear reactors are hoping investors don't realize it. The amount of shielding that you could ever hope to place in an ISO container isn't anywhere near enough.
> as there are no containerized nuclear reactions that I know of.<p><a href="https://world-nuclear.org/information-library/nuclear-power-reactors/small-modular-reactors/small-modular-reactor-smr-design-database" rel="nofollow">https://world-nuclear.org/information-library/nuclear-power-...</a>
Many in design, a few under construction, 2 in operation, by China & Russia.
My point being still: the economics aren't clear yet.
To get paid more money for the additional +480[1] container capacity you gain over the ships life.<p>1. I'm ball-parking an onboard nuclear source would take up the equivalent displacement as 20-50 containers.
having to change batteries every 2 years instead of every trip would be one. Saving few tons would be another
What about the scenario where you just want to refuel? Shuffling containers around just to get the batteries out seems suboptimal.
Placing/moving containers for some specific loading/unloading goal has been a solved problem for a while.<p>You can imagine this needs solving pretty hardcore optimization problems.
Refuelling a cargo ship can take over a day. Quite a boring but well paid job.<p>How many kwh are you lifting at a time with a container? How many kwh are you pumping in the same period?
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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.
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!<p>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.
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.
My guess is not every port can supply bunker fuel. It prob makes sense to load up when the ship is near a refinery and then make several trips before refueling.
Ah, so what you are saying is we are not going to need to make significant compromises to the ship's cargo capacity, but we are impacting the total max range significantly? Is a fully fuelled ship capable of much more than 5k km?
But 5000km is shorter than many major routes, right?<p>Shanghai to Los Angeles is more than double that
The route length isn't important, only the longest distance between ports that you can recharge at. Cargo ships regularly slow steam (I.e. run the engine slow to improve fuel-efficiency) and stopping to recharge batteries at multiple ports to reduce the batteries needed is the exact same concept - sacrificing speed to improve fuel costs.<p>Shanghai to LA is probably the worst example (since the pacific ocean is basically the emptiest spot on the planet, as land/port frequency goes), but Hawaii still exists and they could recharge there.
How does Hawaii produce its power? I can't imagine they have tons of capacity.<p>EDIT: Seems like they mostly use imported oil, so saying "bring us a bunch of oil and we'll charge your batteries with it" seems like the ship is just burning oil with extra steps.
I bet these batteries would be standard container sized and they could be shipped as normal containers would be wherever cheap power is available from nuclear or solar or maybe water. Australia could be huge here, back in 2024 there were news of a six gigawatt solar farm in remote Northern Australia. Based on my very vague knowledge of the geography I presume there's plenty more desert to build solar there. Charge the battery-containers, ship them to China.
I don’t understand why Hawaii doesn’t have more solar. Gotta be a lot cheaper than imported oil, even with the the US solar premium.
In any case, the near-term use case isn’t across the Pacific, it’s to other Asian ports, of which there are numerous very large ones in reasonably close proximity. Think Singapore, Japan, Korea, and so on, all of which are well within 5000km of Chinese ports.
The recharging infrastructure for such a vessel would be an interesting challenge. Likewise if those batteries caught fire.
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 .<p>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.
That also means you can trivially optimize your fuel/cargo ratios. Going across the pacific? Just load 200 more battery containers. Singapore to China right after? Room for 400 FEUs more than normal.
It’s not quite “just”. A way to safely and efficiently connect and disconnect them would be needed.
A quick googling suggests that unloading such a vessel takes at least a couple of days, more likely 3-4.<p>Assuming two days available to charge the vessel, you'd need about 100MW continuous. Not trivial, but doable.<p>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't a new challenge and b) the alternative isn't exactly risk free either; we've seen plenty of oil spills from ships.
The fire thing comes up with cars all the time. Petrol cars are vastly more likely to catch fire, but are a bit easier to extinguish.<p>I can only imaging how hard it is to put out a ship fire, but is there any reason to see that the situation would be different? Bunker fuel appears to be less flammable.
>Petrol cars are vastly more likely to catch fire, but are a bit easier to extinguish.<p>Petrol cars at most marginally more likely to catch fire, if at all. They cannot catch fire by simply being submerged in a foot of water, like an EV can. They are far easier to extinguish than EVs, which are practically unextinguishable and can reignite weeks or months later. You can use a fire extinguisher on a petrol car fire if you catch it early (they are usually electrical fires). If you catch an EV fire early, your best course of action is to run away as fast as possible.<p>Ships are not known to be subject to fires because the types of fuel they use are not generally so volatile, and they are literally surrounded by water which can be pumped to the deck or wherever to drown any fire. Some use diesel, which is difficult to light even with a match. Others use heavy crude oil that looks like tar and would be similarly difficult to ignite accidentally. A battery fire on a ship would be a HUGE problem, as we have seen with ships carrying EVs.<p>I think another often-overlooked risk of EVs is the arson risk. Even if batteries are less likely to catch fire (in the first few years of use, if you baby them), a bad actor can start an unextinguishable fire by shorting out or otherwise igniting a battery pack. This is easy to do and devastating.
> Petrol cars at most marginally more likely to catch fire, if at all.<p>“An American insurer found that just 25 out of 100,000 EVs suffer fire damage.<p>By comparison, 1530 per 100,000 ICE cars experience fire, and hybrid vehicles suffer a much higher risk of 3475 per 100,000 .”<p><a href="https://www.autocar.co.uk/car-news/electric-cars/how-much-fire-risk-are-electric-vehicles" rel="nofollow">https://www.autocar.co.uk/car-news/electric-cars/how-much-fi...</a>
I don't believe those numbers, and even if I did it is a fact that EV fires are far more dangerous than petrol fires. As for hybrid vehicles, you get the best and worst of both worlds including two separate high-energy systems that can catch fire. The average age of an EV is way lower than the average age of a petrol car, and they also tend to be toys for the wealthy who do not abuse them as much as the owners of petrol vehicles abuse theirs. EVs are often ruined by minor accidents or water ingress, and can pose a major fire/explosion risk at any shop that would dare to undertake a repair. Just the other day I heard one EV owner was quoted $12k to repair an issue caused by spilling a bottle of drinking water inside the EV.<p>As I said, the fact that these fires can't be extinguished is a major arson risk, as is their toxicity. Insurers will eventually have to raise their rates to cover the extreme risk posed by EVs. <a href="https://www.himarley.com/news/ev-charging-fires-are-rare-but-insurers-cant-ignore-the-risk/" rel="nofollow">https://www.himarley.com/news/ev-charging-fires-are-rare-but...</a> Storing damaged EVs safely means you need to spread them out like a hundred feet apart or something, so that one of them igniting doesn't start a whole lot of EVs on fire with toxic and inextinguishable flames. There are no solutions to these problems after having EVs on the market for several years, because it's a very hard problem to solve.
And you get downvoted, lol…
Just hang the batteries over the water in containers. Dip them into water if they catch fire.
Electric battery fire is not exactly extinguished with water.
This is largely a misconception that's caused by the fact that EV fires are hard to extinguish with normal water sprays. That is because the bettery packs are designed to be water proof, so it is hard to get the fire patrol's water in. If you can immerse the pack in water, the fire is extinguished without much trouble. That's unlike petroleum fires, where the fuel is lighter than water and liquid, so water spray will boil and spread the fire instead of extinguishing it.
It doesn't need to be extinguished, it just needs to be removed from the ship. Even a second of airtime (and a healthy lateral velocity) might be enough that the ship is out of the explosive radius of the battery.
sure, and what you do with remaining 499 burning containers when your crane is dipping the first one ?
How many ships in port charging at a time? Honestly sounds like a good place to stay a few of those micro reactors lockmart claims to have
The Port of Los Angeles is one of the largest ports in the USA, and has about 1,800 ship arrivals annually.<p>If they were all electric, all of this size, and required a full charge on arrival, you’re talking about (very roughly) 1 GW continuous power requirement for charging the ships. That’s a lot; no bones about it, but it’s not unprecedented - aluminium smelters and data centers are similarly hungry for power.
Wouldn't it be much easier than to put micro reactors on a ship directly? Like on Russian icebreakers that can function on one load of fuel for 3 or 5 years, don't remember exactly but at least 3 years for sure.
If you have one ship to charge, maybe. Ten is in the standard nuclear power plant territory which is politically impossible to build outside of China.
You’re not going to build a nuclear reactor (other than military ones) anywhere near a major port.<p>You power this the same way you power aluminum smelters - you have a big honking grid connection and build the generation capacity in places with more room.
France plans to build 6 more reactors in existing power plants.
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.<p><a href="https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2023-04/DOT-SIB-Testing-Report-Web-Version.pdf" rel="nofollow">https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2023-04/...</a><p><a href="https://old.reddit.com/r/electricvehicles/comments/1m8wlou/electric_ferry_charger/" rel="nofollow">https://old.reddit.com/r/electricvehicles/comments/1m8wlou/e...</a>
Na-ion cells have roughly half the volumetric and gravimetric energy density of NMC, so it's double the weight and double the space. Apart from still being at least as—if not more—expensive as LFP, they also have a sloping voltage curve, vs lithium with is relatively flat, which poses problems for voltage conversion, and these engines are going to be taking kilovolts of power. So I think those problems would need to be solved first.
The biggest problem with Electric is the battery weight, so it makes sense.<p>Ships deliberately use cheaper, less energy dense petroleum products (heavy fuel oil), for pretty much the inverse reasons why airplanes use kerosene.
Not really, kerosene is pretty close to heavy fuel oil on density.<p>Planes run on kerosene because it'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't as much of a problem in middle of sea
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'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.
I guess I want to know "oceanic" means in this instance. Is that just going out into the ocean a short distance? They mention the "Yangtze River Three Gorges 1" 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.
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.
If it were Elon Musk saying it, I’d agree, but this is CATL. They actually do the work.
Hybrid propulsion is already a thing in the marine world (often in navy/military designs):<p>* <a href="https://en.wikipedia.org/wiki/Combined_diesel–electric_and_gas" rel="nofollow">https://en.wikipedia.org/wiki/Combined_diesel–electric_and_g...</a><p>* <a href="https://en.wikipedia.org/wiki/Combined_diesel–electric_and_diesel" rel="nofollow">https://en.wikipedia.org/wiki/Combined_diesel–electric_and_d...</a><p>* <a href="https://en.wikipedia.org/wiki/Integrated_electric_propulsion" rel="nofollow">https://en.wikipedia.org/wiki/Integrated_electric_propulsion</a>
We already have electric oceanic ships. They’re called nuclear submarines.<p>Allseas is putting the reactors on their vessels as well iirc.
US nuclear submarines consume highly-enriched uranium, that's nearly as (and sometimes more) pure as the weapons-grade version. That doesn't mean oceanic reactors aren't possible, it just means that military subs are a bad example.
French nuclear submarines run on 7% enriched fuel, so it's certainly possible to build military submarines that don't need HEU.
There are nuclear icebreakers.<p>Nuclear powered non military ships do exist, it just not economically feasible .
Russia is operating nuclear civil vessels (icebreakers) since 1957
Yep, was just lookin up their recent news on this: <a href="https://www.allseas.com/en/who-we-are/news-and-media/allseas-smr-technology-offers-major-strategic-opportunities-netherlands" rel="nofollow">https://www.allseas.com/en/who-we-are/news-and-media/allseas...</a>
While perhaps not practical for oceanic shipping as is, it's a fun exercise to demonstrate the energy density of nuclear power.
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't have to pay anyone for the space or worry about too many regulations etc.
> I wonder if some kind of big floating energy station could be a thing<p>Congratulations, you have just re-invented offshore (floating) wind turbines. <a href="https://duckduckgo.com/?t=ftsa&q=floating+wind+turbines+&ia=web" rel="nofollow">https://duckduckgo.com/?t=ftsa&q=floating+wind+turbines+&ia=...</a><p>> I guess you don't have to pay anyone for the space or worry about too many regulations etc.<p>I'm ammused you think offshore energy is lawless. It's the same assumption that had the entire maritime community laughing at the clowns behind 'Seasteding" and the amusing MS Satoshi 'cryptoship'.
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?
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.<p>TL;DR marine is the one niche where "we had to make it a lot bigger to hold the batteries" isn'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.
This is overly optimistic.<p>If you expect _oceanic_ ships in 3 year, you need to start building infrastructure today, in multiple ports.<p>If you need to build those infrastructure today, you need to have something standardize.<p>otoh, if all you want are just some prototypes, we have them today already..
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.
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.
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.
Unfortunately, it's not even close. Maybe 1-2% in a highly optimistic scenario.<p>- 20k square meters of hull space<p>- If fully covered with solar panels, on a sunny day, you could expect 1-2 MWh (when averaging in night time)<p>- Current diesel engines typically output 60MWh continuously while underway.<p>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.<p>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).
Did you mean MW rather than MWh?
Yea mixed up my units in a couple places. Should be:<p>- Solar: 1–2 MW of average power; ~24–48 MWh of energy per day.<p>- Diesel: about 60 MW of mechanical power while underway; ~1,440 MWh of energy per day.
60 MWh continuously means inf MW.
Your math seem to work out, but I don't like the incoherent use if energy units.<p>60 MWh per what? Per hour? thats just 60 MW continuous POWER or 1440 MWh ENERGY per day.
Lithium is not scarce, and not a limiting factor for scaling up batteries.<p>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.<p>Whether battery ocean shipping containers make technical sense is a different question, but I wouldn't worry about lithium use!
All resources are "scarce" at very low price points, below which most nations are unable or unwilling to extract them.<p>Lithium, rare earth metals, and a bunch of others are only "scarce" 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.<p>Everything can be produced cleanly, safely, etc... but that comes at a price.<p>It's like when employers complain that "nobody wants to work". That needs to be translated to "nobody wants to work for the low wages I'm willing to pay".
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?
What's more scarce is the factory capacity to build the batteries, and the scale of their supply chains. But even that is expanding by 10x every five years. We are currently building more than a TWh per year of batteries.<p>If there is demand for batteries in ships, it is going to be far smaller than for cars, which is currently 80% of battery demand (the rest is mostly grid storage). So ship batteries will at most slow the fall of battery pricing by a small amount.
No, but with wind it's possible. Either vertical windmills or sails with modern signal processing.<p>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.
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't the problem for the most part.
Smaller boats sure, but ocean going cargo vessels? There are some serious challenges!<p>Try to approximate the area needed to generate e.g. 50MW propulsion. It would be measured in hectares.
No.<p>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.<p>Not to mention that a container ship’s deck is typically completely covered with, well, containers.<p>Also, lithium isn’t scarce.
> Not to mention that a container ship’s deck is typically completely covered with, well, containers.<p>I guess in theory that could be solved either with huge removable panels around the containers (to be "put aside" 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.<p>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, though<p>But, I guess it wouldn't be worthwhile.
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's still going to be slower unless you do something dramatic like fly a huge PV array as a kite or something)<p>Besides PV, there'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's not nothing, but we're some ways away.<p>I wouldn't underestimate what creative and dedicated engineers can accomplish.
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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?
There are multiple electric ferries already in operation:<p><a href="https://en.wikipedia.org/wiki/MV_Ampere" rel="nofollow">https://en.wikipedia.org/wiki/MV_Ampere</a><p>They are quite impressive but they are still very far away from your average ocean going cargo vessel.
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 'oceanic ship' than a 20 minute ferry ride.<p>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's cool too. It'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.<p><a href="https://en.wikipedia.org/wiki/MV_Wenatchee" rel="nofollow">https://en.wikipedia.org/wiki/MV_Wenatchee</a>
Absolutely, but that's how this starts. Boats too started as ferries, it took many, many years before boats purposefully went into blue water. Ferries are a great testbed, they have lots of cycles and they are a pre-cursor to coastal and then eventually larger ocean going vessels, which I predict will go diesel-electric before they go all electric.
> eventually larger ocean going vessels, which I predict will go diesel-electric before they go all electric.<p>Diesel-electric, particularly when using Azipods, is great when you need to do a lot of maneuvering in narrow spaces like ports. But for long-haul it's hard to beat the economics of a two-stroke direct drive diesel.<p>Maybe a hybrid concept for a long-haul ship would be using a direct drive two-stroke main engine, but the auxiliary diesels replaced by batteries?
> Boats too started as ferries, it took many, many years before boats purposefully went into blue water<p>What kind of boats are you talking about?
So, people start pretty early with rafts. A raft isn't a boat it's just a collection of stuff which floats ie is buoyant - so, with care, you can board the raft and cross a stretch of water without swimming, which is convenient. Boats incrementally improve on this by having a distinct "inside" of the boat which needn't be buoyant, separated from the outside by waterproofing. A canoe or a coracle would be examples of boats you can easily invent once you've seen rafts.<p>Most easy to invent types of boat are great if there are no waves. On a river there are basically never waves (yes rapids exist, no that's not common)<p>However at sea waves are commonplace. Situations where waves are minimal are extremely rare, usually occurring seasonally, when tides are smaller than usual and weather is calm. Sea Lion (the never attempted German invasion of mainland Britain) was predicated on absolutely calm sea because it would have used towed river barges to land troops. If there's a moderate sea but you green light the operation anyway, all your infantry drown and you've just lost the war immediately.<p>To be successful at sea you want even more buoyancy, to put the top of the waterproof outer parts of the boat above the waves, and you probably also want a keel, rather than having the vessel's bottom flat and sort of resting on the water which won't work well with waves. None of this is impossible, or even especially difficult with quite ancient technology, but it's not trivial, you definitely won't go from rafts to ocean-going freight transport in one attempt.
> Electrifying ferries is great, but this particular one has a run time of 20 minutes (and a charge time of 10 minutes).<p>And this one, under construction now, will have a run time of 90 minutes and charge time of 40 minutes:<p><a href="https://spectrum.ieee.org/electric-boat-battery-ship-ferry" rel="nofollow">https://spectrum.ieee.org/electric-boat-battery-ship-ferry</a>
<a href="https://news.ycombinator.com/item?id=45844832">https://news.ycombinator.com/item?id=45844832</a><p>Sibling comment is perfectly correct that it starts small and ramps up.<p>From that article:<p>> "The ferry format, with its high-frequency turnaround, relatively short segment distances, and shore-based rapid charging, is one of the most promising early use cases for electrification in the maritime sector. Maritime electrification has gained momentum over the past few years"<p>Early. Momentum.<p>Moving some noticeable percentage of ships away from fossil fuels is still a win.
Yeah, the oceanic part is the issue. Going between two close points, at least one of which has electricity, is easy.
Energy density doesn't seem to matter much in boats. Massive ships carry astronomical amounts of cargo.
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.
... and energy densities of batteries will _stay_ well below that of tanks of hydrocarbons, as <a href="https://web.archive.org/web/20130204210054/http://h30565.www3.hp.com/t5/Feature-Articles/How-Good-Can-Batteries-Get/ba-p/994" rel="nofollow">https://web.archive.org/web/20130204210054/http://h30565.www...</a> explains.
The US with its sunk cost and political power base in fossil fuels is losing the innovators dilemma at a large scale here.
It would be amazing if they could leverage the container system, but instead of goods, there'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.
If we ever end up doing that it would mean terrible things for the state of our regulatory landscape.<p>A completely optimized high capacity cargo rail line can move 500 rail cars per hour. That'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.<p>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.
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.
Not even the Russians could decommission their nuclear subs properly. I'm relatively sure that random semi-shading shipping companies wouldn't either.<p>In a perfect world however... endless cooling water unless they're in some shallow harbor. Would be the perfect application.
> In a perfect world however... endless cooling water unless they're in some shallow harbor. Would be the perfect application.<p>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't hit a bridge support but a nuclear powered vessel.<p>Nuclear powered ships <i>only</i> 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 <i>and will</i> shoot and sink anything with the potential of becoming a threat.
The germans tried that in the 60s see <a href="https://en.wikipedia.org/wiki/Otto_Hahn_(ship)" rel="nofollow">https://en.wikipedia.org/wiki/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.<p>Even navies are moving away from nuclear power due to how expensive it is.
I wonder if nuclear containerships can be developed and have enough power to pull a train of containerships.
<a href="https://en.wikipedia.org/wiki/Sevmorput" rel="nofollow">https://en.wikipedia.org/wiki/Sevmorput</a>
certainly there exist nuclear ships with enough power but I fail to see how you would feasibly tug a train of containerships
Cars have regenerative breaking which is a help in urban areas.<p>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.
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.<p>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.
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.<p>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.<p>Suffice to say, I'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 / synthetic fuel by then but I wouldn't hold my breath.
<i>Regenerative braking for boats would be a complete waste.</i><p>Unless you have a large sail to generate thrust to spin the propeller...
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.
Wind, large surface area for solar<p>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).<p>Ideally a combination of sails coupled with batteries and wave generators sounds like it would be very energy efficient.
I guess if it works for cars then boats should too
Sails [0] [1] [2] are obviously more sustainable than the gigantic industry needed around batteries this size. That'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.<p>[0] <a href="https://www.towt.eu/en/home/" rel="nofollow">https://www.towt.eu/en/home/</a><p>[1] <a href="https://www.neoline.eu/" rel="nofollow">https://www.neoline.eu/</a><p>[2] <a href="https://graindesail.com/fr/voilier-cargo-grain-de-sail-3/" rel="nofollow">https://graindesail.com/fr/voilier-cargo-grain-de-sail-3/</a>
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 wonder how much the jeans would cost if the price of shipping (i.e. the cost per container ocean mile) were to double.