Batteries will not have the requisite energy density for anything remotely long-journey--notably Panamax+ container ships which, sadly, are also the biggest carbon & sulfur (yes low-sulfer regs/fuel exists, but not everywhere) polluters.
These large ships will likely be de-carbonized either with ammonia turbines or fuel cells. Mann has already been running a PoC ammonia turbine ship for about 4 years--the last 2 undergoing proper blue-water "sea-trials" journeys.
But I have my doubts. There's still no economically viable way to produce "green" ammonia at scale. It's hazardous to handle and less energy dense than liquid hydrocarbons.
Which is why we won't be burning ammonia and shouldn't even try.
We already have an entire, scaled up industry of producing artificial fuel in a non-petrochemical route: It's where the ethanol in your gas tank comes from.
Farming will be easier to electrify than shipping, or it might not even need to be, and then we will have ample supply (at least here in the US) of energy dense fuels produced through non-petrochemical needs
Growing corn to turn into ethanol to burn isn't like, a carbon negative process right now, but it's also viable today to provide energy dense fuels in a sustainable way to feed our needs like long term storage, compactness, emergencies, and things like planes which won't work with batteries very well.
We already supply enough artificial hydrocarbon fuel through that process to make up 10% of all gasoline burned. As american cars electrify, the corn farmers are going to lose their shit about this subsidy being reduced, so we should just turn it around and have them commit to a larger artificial fuel industry. Our corn growing is already basically a fully socialized industry, let's just lean into it more. Put less corn syrup into random foods like burger buns and put more of it into vats to get energy dense fuel.
It's (technically, barely) an energy positive process, is extremely scalable, is fairly old "tech" such that it won't be owned by one company or country, and the hardest part will be replacing the petrochemical fertilizer.
The real solution though is nuclear powered shipping. There's dozens of nuclear powered ships already and they've been running safely for decades. It's just regulatory roadblocks, but if governments wanted to do it they could.
Military ships are "safe", because they can generally defend themselves. Commercial container ships would be the target of hijacking, to steal the reactor / fuel, or use them as 9/11 ship equivalents.
I wonder why ammonia became the solution that went ahead to prototype and now appears the top candidate for near future low carbon alternative?
You still have to deal with a lot of specialized infrastructure and engine design.
I would have thought something like processing coal or synthesizing ethanol to a more suitable drop in replacement fuel would be easier. Maybe less scalable or outright requires more energy input.
Any carbon-based fuel ultimately depends on a lot of capture infrastructure to be carbon-neutral. In the short term, it's hard to see a path to viability. Ammonia is easy to synthesize, ingredients are literally water and air, liquefies at achievable pressure, and can be directly consumed in a fuel cell or combustion engine. It's corrosive, but only to certain materials (late transition metals and aluminum), and toxic, but only in high concentrations (the body naturally contains a few ppm of ammonia at all times). It's biodegradable, so you don't worry as much about spills. It's flammable, but not extremely so like hydrogen.
Ammonia is not going to happen. Sorry. There's no way we're going to allow floating chemical weapons maintained by shipping companies that not just cut corners but angle-grind them.
Methane works perfectly well for shipping. It's cheap, abundant, and we already have all the infrastructure for it.
And to fully decarbonize it, we'll just shift to biogas or power-to-gas.
Batteries for ships seems really silly but at the same time its the perfect regime for a ridiculous quantity potentially hazardous items. Nuclear obviously works well here too. You have an unlimited amount of water with which to fight any fires or cool off equipment and you could theoretically engineer a way to dump the entire assembly into the ocean in an emergency.
Hydrodynamics are brutal, but the square-cube law works in your favor. The ocean doesn't care about what's inside your ship. Just the surface of it. The mass is mostly irrelevant. This is why cargo vessels are so large. The bigger the boat the bigger the energy density benefit.
The only real problem is the cost. To compete with a supermax you would need something like two billion dollars worth of batteries to survive a transpacific voyage.
for sailing yachts that makes sense. They would use wind for most movement. While in harbor though they want the finer control that being under power allows - they don't need high speed/high power then though. They also don't spend a lot of time in this situation.
They're more like sail assisted than really "sailing" as such. Worth doing in some cases but saves maybe 10% of fuel under optimal wind conditions. The most suitable vessels will tend to be bulkers, car carriers, and tankers. Container ships are actually the hardest to add sails because they interfere with the stacks and the port cranes.
The Neoliner Origin is a joke. It's a marketing stunt to greenwash the importation of low-volume luxury goods like cosmetics for rich customers who want to tell their friends about how they're saving the planet. The design can't scale up to transport bulk cargo in a cost effective way.
It makes so much sense. The one's I've seen can be engaged in recovery mode while running your sails, so you can spin the prop and generate electricity. They only get a few hours run time fully charged, but that's plenty for port maneuvers or trip to pick up your crab pots.
More modern battery chemistries are less hazardous as well. LFP for example is both cheaper and more stable, just at the cost of energy density. Which might be fine if you have a giant ship that can handle a large volume and mass of batteries to save on fuel costs.
> You have an unlimited amount of water with which to fight any fires
Fire on a ship is extremely dangerous. Think about what your training and your first instincts both tell you to do if there's a serious fire. Where I am the training starts with four words: "Get out. Stay out". But you can't just leave a ship, in the ocean you will drown. Even lifeboats, if they're available and can be used, are much more dangerous than we'd like.
Nuclear power isn't going to happen for merchant vessels (outside some very limited cases like Russia's state owned icebreakers). Unlike superpower navies, shipping lines can't afford to train and pay nuclear engineers plus the necessary armed security personnel. Many countries refuse to allow commercial nuclear vessels to enter their ports due to fears over terrorist attacks, or environmental catastrophe from an accidental sinking.
Unlike superpower navies, shipping lines can't afford to train and pay nuclear engineers plus the necessary armed security personnel.
Yeah, people are probably better off not knowing how insanely cheap shipping lines are. Shipping is one of those parts of the economy and trade that is simultaneously advanced and very old fashioned (in the rickety sense) at the same time.
It's quite fun to do the math on what it would take to power the largest container ships by batteries. It's not physically impossible but it would displace a good chunk of the usable cargo load.
A single container can contain up to 8mwh of capacity. Just 125 of those gets you to 1gwh. Depending on how quick the ship goes, you might need 1-2 gwh per day. You can conserve energy by going slower. But out of 14K containers, reserving maybe a third for battery could power a ship for quite some time. Enough to e.g. cross the Pacific. There are obvious issues with weight and balance. The volume is doable but the weight creates a lot of issues.
Another challenge is indeed the cost of these batteries. That's about an order of magnitude of where it needs to be to make it financially realistic. But batteries coming down further in cost could make this more feasible. And it's not like these huge container ships are cheap. A couple of tens or even hundreds of millions of dollars worth of battery is reasonable. Billions would be unreasonable.
There are traditionally powered ships carrying many thousands of EVs with batteries already. So, putting a few gwh of battery on a ship is already happening; we're just not using them to move the ship. And batteries made in China are typically shipped to the US and elsewhere for integrating into cars, grid storage, etc. as well. If you can ship it, you might as well use it. And of course battery powered ships are already very popular for lighter short haul like ferries, tug boats, small transport barges on rivers, etc. There are plenty of them operational without major issues. Safety issues seem to be so far not a blocker.
The incentive here is not burning a millions of dollars worth of fuel per journey. Container ships use a lot of fuel. That adds up fairly rapidly to offsetting the cost of the battery. I think the question is not if batteries will be used on ships but how much batteries typical ships will have.
> A single container can contain up to 8mwh of capacity.
That's about 10 months of power for my home and car (gas heating). A 40' container on my drive or buried in the garden would power the house through the winter. It's crazy when you think how solvable season-shifting domestic power use is once you exclude the $1.5m price tag.
Assuming 100$/kWh and those 2G$ (giga/billion), a full charge would be 20 GWh.
Realistically: probably exposed wire like on regular high voltage pylons.
Hooked to a not-too-far (the wires will be on the larger end, but you likely don't want the other end to be anywhere it could get in the way of cargo operations, and given the voltages involved, you can probably get half way across the city before it really begins to matter) grid battery bank that normally takes care of day-to-day scale grid balancing/energy arbitrage.
Then you just run a (group of) wires to the ship and apply basically the same principles as those DC fast charge stations for cars, except that you feed the high power DC link of the charging cable from the shore-side battery through much more efficient and importantly cheaper DC/DC regulators instead of involving transformers and AC.
You obviously have remote-controlled switches and circuit breakers to keep those cables grounded while the workers hook them up.
You'd probably have several DC links that have their own DC/DC regulators and can be split between ships.
Mostly also because there's a limit to how high-current any individual cable/connector is made in practice and because you want to use the current rating on your DC/DC converters and the thick-but-off-the-shelf cables between the battery park and the pier.
I assumed they would use sea water for cooling but that doesn't seem to be the case? Maybe the battery coolant is cooled using some sort of sea water heat exchanger?
You really don't want to cool anything with sea water directly. It's corrosive due to the salt and contains all kinds of fun things from flotsam to critters, some of which might make a home in your cooling loop. in this case, additionally, sea water is conductive and that's not acceptable in a battery.
However, feeding the coolant through some sort of heat exchange with the sea water is very likely something they do.
Yes, that's the absolute norm (you often also want to cool the exhaust pipe itself and there you often see coolant water pumped straight into the exhaust). That's the obvious thing to do: You do have a huge reservoir of readily available coolant, tapping it is the sensible thing to do :) That's why I fully expect them to run their coolant through some heat exchange with sea water.
Fossil fuel engines are significantly less efficient than electric ones... so need a lot more cooling. I'm sure getting rid of the need for that would be a nice win that might be practical with electric engines.
Batteries and electric motors are fussy about temperature, you still need thermal management. Probably not as large a system, but you might need a heater or sub ambient capability.
Also saltwater is conductive so if you submerged your batteries in it, you'd have an immediate short circuit. It's definitely through a heat exchanger.
There’s got to be some setup out there were we are able to harness wind energy (and solar to a smaller extent) to significantly increase the ranges here. Not a hundred years ago, we had cargo ships sail solely on wind power so enough energy is there for the taking.
There are a few that are sailing, they are pretty modest size. There are plans for more and larger vessels but I don't think anyone expects widescale deployment anytime soon.
Question is can they get enough power to be useful. Marine diesel engines are very fuel efficient, fuel oil is very energy dense, and they need to run for a long time. Electric cars work in part because people expect to refuel few couple hours anyway. Enough batteries to cross the ocean is going to be vastly worse.
The only useful picture in the article is a "solar powered board", which doesn't give a good scale but appears to be barely enough solar power for the rich owner to enjoy their luxuries and will barely move all day while forced to anchor all day. I'm sure it can go really fast on battery power, but not for long. Sails would be a better primary movement source with battery for in harbor navigation or when the wind stops backup only.
A lot of ships don't go across oceans and can benefit from batteries. Think ferries, feeder ships, river transport. Those all dock in relatively predictable intervals.
As a crazy thought: On predictable routes in shallow enough water, implement an underwater power source similar in function (if not physically similar) to overhead electric bus/trolley power lines? The boats would move along their routes with a cable running down to to a connector that slides along the power source.
I'm imagining channels in a busy waterway or a regular ferry route. Of course it needs economy of scale, but at that point everyone saves on batteries, etc. Unless there are submarines, I don't know what would pass under the boat and cut the connection.
Maybe watercraft usage or routes aren't predictable enough? Maybe the sliding connector is too expensive underwater, especially in sea water.
sea water is too corrosive and too conductive. You could make a single overhead cable and use sea water as your return work. However it wouldn't be practical since ships multiple stories tall need to pass under the wire (and draw a lot of power), while also tiny fishing boards that couldn't even get a pole that high.
The same problem with height would also be an issue for the underwater thing. Quick googling suggests a very large container ship might have a draft of 16-17m when fully loaded. Probably you want the catenary at 20m depth then. How does a small get their pantograph (or whatever you'd call it) down to that depth, and then move forwards without the pantograph sticking 20m down creating a huge amount of drag. Not to mention how do you make the connection between the pantograph and the catenary in the (conductive) sea water?
> Probably you want the catenary at 20m depth then. How does a small get their pantograph (or whatever you'd call it) down to that depth,
Does the connection from the 'pantograph' to the boat need to be rigid? Use a cable? Maybe it's not for the smaller boats which can't handle a 20m (probably more like 40m for the angle and slack) cable, but also need less power and thus pollute less.
> and then move forwards without the pantograph sticking 20m down creating a huge amount of drag
Presumably, the catenary's route would be cleared of obstructions - maybe even on a frame elevated over the floor, maybe at relatively constant depth - or do I misunderstand? Would a 40m cable cause that much drag? Obviously the pantograph would have to be low friction and highly reliable.
I had always imagined a system of autonomous submarines that function as tugboats along popular routes and then container ships would just function as barges that are hauled by these autonomous submarines. These submarines recharge their batteries automatically by docking to underwater charging stations.
The maintenance of these power points would be astronomical, even if the basic theory could work, which I'm not 100% sure of. You'd have a single high-voltage cable, a pickup pantograph that wraps around the cable acting like a transformer that wheels along the cable, and AC current in the cable with the water itself being the ground reference. I can't imagine any other way it could work.
Interesting. Generally, waterborne freight is far cheaper than rail. Also, at least sometimes you might need to transfer between modes - ship to rail then rail to ship. But with the underwater catenary solution now we're talking about new infrastructure (not to mention R&D, etc.).
As a sort of transitive analysis: Standard waterborne energy costs are included in the superior pricing of waterborne freight compared to rail. If the underwater catenary solution is competitive to standard waterborne energy costs, it beats rail easily. If the underwater catenary is not competitive, it has no value anyway.
It could still have value if we price in, as we should, the externality of GHG output. THe underwater catenary could reduce GHG output in busy waterways by powering boats that don't have batteries.
> Question is can they get enough power to be useful. Marine diesel engines are very fuel efficient, fuel oil is very energy dense, and they need to run for a long time.
Washington State Ferries refit one of their largest ferries (190-car capacity) as a hybrid recently. They replaced two diesel engines with batteries, leaving the other two engines in place. This provides for significant fuel savings. When shore charging is implemented, fuel use will be reduced even more.
I imagine there are also uses where batteries fully replace engines. I've got a tiny boat for casual fishing, you tend not to use the engine that much, and electric propulsion is likely quieter and can probably modulate to slower speeds which could replace a separate electric trolling motor.
Batteries will not have the requisite energy density for anything remotely long-journey--notably Panamax+ container ships which, sadly, are also the biggest carbon & sulfur (yes low-sulfer regs/fuel exists, but not everywhere) polluters.
These large ships will likely be de-carbonized either with ammonia turbines or fuel cells. Mann has already been running a PoC ammonia turbine ship for about 4 years--the last 2 undergoing proper blue-water "sea-trials" journeys.
If ammonia fuel happens at all for merchant vessels then for efficiency reasons it will be run through reciprocating engines, not turbines.
https://www.wartsila.com/marine/products/engines-and-generat...
But I have my doubts. There's still no economically viable way to produce "green" ammonia at scale. It's hazardous to handle and less energy dense than liquid hydrocarbons.
Which is why we won't be burning ammonia and shouldn't even try.
We already have an entire, scaled up industry of producing artificial fuel in a non-petrochemical route: It's where the ethanol in your gas tank comes from.
Farming will be easier to electrify than shipping, or it might not even need to be, and then we will have ample supply (at least here in the US) of energy dense fuels produced through non-petrochemical needs
Growing corn to turn into ethanol to burn isn't like, a carbon negative process right now, but it's also viable today to provide energy dense fuels in a sustainable way to feed our needs like long term storage, compactness, emergencies, and things like planes which won't work with batteries very well.
We already supply enough artificial hydrocarbon fuel through that process to make up 10% of all gasoline burned. As american cars electrify, the corn farmers are going to lose their shit about this subsidy being reduced, so we should just turn it around and have them commit to a larger artificial fuel industry. Our corn growing is already basically a fully socialized industry, let's just lean into it more. Put less corn syrup into random foods like burger buns and put more of it into vats to get energy dense fuel.
It's (technically, barely) an energy positive process, is extremely scalable, is fairly old "tech" such that it won't be owned by one company or country, and the hardest part will be replacing the petrochemical fertilizer.
Oh, ethanol is a more energy dense fuel too.
The real solution though is nuclear powered shipping. There's dozens of nuclear powered ships already and they've been running safely for decades. It's just regulatory roadblocks, but if governments wanted to do it they could.
Military ships are "safe", because they can generally defend themselves. Commercial container ships would be the target of hijacking, to steal the reactor / fuel, or use them as 9/11 ship equivalents.
Regulation is not always bad.
I wonder why ammonia became the solution that went ahead to prototype and now appears the top candidate for near future low carbon alternative?
You still have to deal with a lot of specialized infrastructure and engine design.
I would have thought something like processing coal or synthesizing ethanol to a more suitable drop in replacement fuel would be easier. Maybe less scalable or outright requires more energy input.
Any carbon-based fuel ultimately depends on a lot of capture infrastructure to be carbon-neutral. In the short term, it's hard to see a path to viability. Ammonia is easy to synthesize, ingredients are literally water and air, liquefies at achievable pressure, and can be directly consumed in a fuel cell or combustion engine. It's corrosive, but only to certain materials (late transition metals and aluminum), and toxic, but only in high concentrations (the body naturally contains a few ppm of ammonia at all times). It's biodegradable, so you don't worry as much about spills. It's flammable, but not extremely so like hydrogen.
Ammonia is not going to happen. Sorry. There's no way we're going to allow floating chemical weapons maintained by shipping companies that not just cut corners but angle-grind them.
Methane works perfectly well for shipping. It's cheap, abundant, and we already have all the infrastructure for it.
And to fully decarbonize it, we'll just shift to biogas or power-to-gas.
turning off sulfur exhaust caused fewer clouds, helping to lower earth's albedo and accelerate global heating. no wins without losses either way
Batteries for ships seems really silly but at the same time its the perfect regime for a ridiculous quantity potentially hazardous items. Nuclear obviously works well here too. You have an unlimited amount of water with which to fight any fires or cool off equipment and you could theoretically engineer a way to dump the entire assembly into the ocean in an emergency.
Hydrodynamics are brutal, but the square-cube law works in your favor. The ocean doesn't care about what's inside your ship. Just the surface of it. The mass is mostly irrelevant. This is why cargo vessels are so large. The bigger the boat the bigger the energy density benefit.
The only real problem is the cost. To compete with a supermax you would need something like two billion dollars worth of batteries to survive a transpacific voyage.
I hear you and while this is out of scope for the article a lot of sailing yachts are being converted to electric motors.
for sailing yachts that makes sense. They would use wind for most movement. While in harbor though they want the finer control that being under power allows - they don't need high speed/high power then though. They also don't spend a lot of time in this situation.
Electric tugs are now a thing to do similar for big ships.
A step before that is to have shore power to run things when in port.
In general stopping pollution near populated areas and busy ports is a bigger win and so a good place to start.
I think sailing uses mainly some other kind of energy source.
Right. And sailing container ships seem to also be coming back into vogue.
They're more like sail assisted than really "sailing" as such. Worth doing in some cases but saves maybe 10% of fuel under optimal wind conditions. The most suitable vessels will tend to be bulkers, car carriers, and tankers. Container ships are actually the hardest to add sails because they interfere with the stacks and the port cranes.
10% is a lot though.
The Neoliner Origin is a pretty interesting ship. Perhaps more ships like it will start to show up as oil gets more expensive.
https://en.wikipedia.org/wiki/Neoliner_Origin
The Neoliner Origin is a joke. It's a marketing stunt to greenwash the importation of low-volume luxury goods like cosmetics for rich customers who want to tell their friends about how they're saving the planet. The design can't scale up to transport bulk cargo in a cost effective way.
It makes so much sense. The one's I've seen can be engaged in recovery mode while running your sails, so you can spin the prop and generate electricity. They only get a few hours run time fully charged, but that's plenty for port maneuvers or trip to pick up your crab pots.
More modern battery chemistries are less hazardous as well. LFP for example is both cheaper and more stable, just at the cost of energy density. Which might be fine if you have a giant ship that can handle a large volume and mass of batteries to save on fuel costs.
TFA specifically said volume is the last thing a ship operator wants to sacrifice. Volume used for batteries is volume that cannot be used for cargo.
> You have an unlimited amount of water with which to fight any fires
Fire on a ship is extremely dangerous. Think about what your training and your first instincts both tell you to do if there's a serious fire. Where I am the training starts with four words: "Get out. Stay out". But you can't just leave a ship, in the ocean you will drown. Even lifeboats, if they're available and can be used, are much more dangerous than we'd like.
Nuclear power isn't going to happen for merchant vessels (outside some very limited cases like Russia's state owned icebreakers). Unlike superpower navies, shipping lines can't afford to train and pay nuclear engineers plus the necessary armed security personnel. Many countries refuse to allow commercial nuclear vessels to enter their ports due to fears over terrorist attacks, or environmental catastrophe from an accidental sinking.
Unlike superpower navies, shipping lines can't afford to train and pay nuclear engineers plus the necessary armed security personnel.
Yeah, people are probably better off not knowing how insanely cheap shipping lines are. Shipping is one of those parts of the economy and trade that is simultaneously advanced and very old fashioned (in the rickety sense) at the same time.
It's quite fun to do the math on what it would take to power the largest container ships by batteries. It's not physically impossible but it would displace a good chunk of the usable cargo load.
A single container can contain up to 8mwh of capacity. Just 125 of those gets you to 1gwh. Depending on how quick the ship goes, you might need 1-2 gwh per day. You can conserve energy by going slower. But out of 14K containers, reserving maybe a third for battery could power a ship for quite some time. Enough to e.g. cross the Pacific. There are obvious issues with weight and balance. The volume is doable but the weight creates a lot of issues.
Another challenge is indeed the cost of these batteries. That's about an order of magnitude of where it needs to be to make it financially realistic. But batteries coming down further in cost could make this more feasible. And it's not like these huge container ships are cheap. A couple of tens or even hundreds of millions of dollars worth of battery is reasonable. Billions would be unreasonable.
There are traditionally powered ships carrying many thousands of EVs with batteries already. So, putting a few gwh of battery on a ship is already happening; we're just not using them to move the ship. And batteries made in China are typically shipped to the US and elsewhere for integrating into cars, grid storage, etc. as well. If you can ship it, you might as well use it. And of course battery powered ships are already very popular for lighter short haul like ferries, tug boats, small transport barges on rivers, etc. There are plenty of them operational without major issues. Safety issues seem to be so far not a blocker.
The incentive here is not burning a millions of dollars worth of fuel per journey. Container ships use a lot of fuel. That adds up fairly rapidly to offsetting the cost of the battery. I think the question is not if batteries will be used on ships but how much batteries typical ships will have.
> A single container can contain up to 8mwh of capacity.
That's about 10 months of power for my home and car (gas heating). A 40' container on my drive or buried in the garden would power the house through the winter. It's crazy when you think how solvable season-shifting domestic power use is once you exclude the $1.5m price tag.
A lot of things are solvable if you don't care how much they cost
What kind of shore-to-ship power connection would you need to recharge the batteries while the ship is unloaded/loaded?
Assuming 100$/kWh and those 2G$ (giga/billion), a full charge would be 20 GWh.
Realistically: probably exposed wire like on regular high voltage pylons. Hooked to a not-too-far (the wires will be on the larger end, but you likely don't want the other end to be anywhere it could get in the way of cargo operations, and given the voltages involved, you can probably get half way across the city before it really begins to matter) grid battery bank that normally takes care of day-to-day scale grid balancing/energy arbitrage.
Then you just run a (group of) wires to the ship and apply basically the same principles as those DC fast charge stations for cars, except that you feed the high power DC link of the charging cable from the shore-side battery through much more efficient and importantly cheaper DC/DC regulators instead of involving transformers and AC.
You obviously have remote-controlled switches and circuit breakers to keep those cables grounded while the workers hook them up. You'd probably have several DC links that have their own DC/DC regulators and can be split between ships. Mostly also because there's a limit to how high-current any individual cable/connector is made in practice and because you want to use the current rating on your DC/DC converters and the thick-but-off-the-shelf cables between the battery park and the pier.
Note that these are huge: the largest grid battery plant in operation (according to https://en.wikipedia.org/wiki/Battery_energy_storage_system ) is only 4GWh, so 1/5th of such a ship.
I assumed they would use sea water for cooling but that doesn't seem to be the case? Maybe the battery coolant is cooled using some sort of sea water heat exchanger?
A closed loop is probably easier to maintain compared to pumping caustic saltwater and all the things in it near batteries.
You really don't want to cool anything with sea water directly. It's corrosive due to the salt and contains all kinds of fun things from flotsam to critters, some of which might make a home in your cooling loop. in this case, additionally, sea water is conductive and that's not acceptable in a battery.
However, feeding the coolant through some sort of heat exchange with the sea water is very likely something they do.
> However, feeding the coolant through some sort of heat exchange with the sea water is very likely something they do.
Aren't ship engines usually cooled with sea water already (through a heat exchanger, not directly)? So it's not really something new
Yes, that's the absolute norm (you often also want to cool the exhaust pipe itself and there you often see coolant water pumped straight into the exhaust). That's the obvious thing to do: You do have a huge reservoir of readily available coolant, tapping it is the sensible thing to do :) That's why I fully expect them to run their coolant through some heat exchange with sea water.
Fossil fuel engines are significantly less efficient than electric ones... so need a lot more cooling. I'm sure getting rid of the need for that would be a nice win that might be practical with electric engines.
Batteries and electric motors are fussy about temperature, you still need thermal management. Probably not as large a system, but you might need a heater or sub ambient capability.
Also saltwater is conductive so if you submerged your batteries in it, you'd have an immediate short circuit. It's definitely through a heat exchanger.
The immersion fluid has to be non conductive and non corrosive. Hence the choice of oil (flammable) or weird fluorocarbons.
There’s got to be some setup out there were we are able to harness wind energy (and solar to a smaller extent) to significantly increase the ranges here. Not a hundred years ago, we had cargo ships sail solely on wind power so enough energy is there for the taking.
There are a few that are sailing, they are pretty modest size. There are plans for more and larger vessels but I don't think anyone expects widescale deployment anytime soon.
https://gcaptain.com/the-return-of-sail-power-cargo-ships-ar...
The travel speed was significantly slower. To the point of not being acceptable in today's world.
Question is can they get enough power to be useful. Marine diesel engines are very fuel efficient, fuel oil is very energy dense, and they need to run for a long time. Electric cars work in part because people expect to refuel few couple hours anyway. Enough batteries to cross the ocean is going to be vastly worse.
The only useful picture in the article is a "solar powered board", which doesn't give a good scale but appears to be barely enough solar power for the rich owner to enjoy their luxuries and will barely move all day while forced to anchor all day. I'm sure it can go really fast on battery power, but not for long. Sails would be a better primary movement source with battery for in harbor navigation or when the wind stops backup only.
A lot of ships don't go across oceans and can benefit from batteries. Think ferries, feeder ships, river transport. Those all dock in relatively predictable intervals.
As a crazy thought: On predictable routes in shallow enough water, implement an underwater power source similar in function (if not physically similar) to overhead electric bus/trolley power lines? The boats would move along their routes with a cable running down to to a connector that slides along the power source.
I'm imagining channels in a busy waterway or a regular ferry route. Of course it needs economy of scale, but at that point everyone saves on batteries, etc. Unless there are submarines, I don't know what would pass under the boat and cut the connection.
Maybe watercraft usage or routes aren't predictable enough? Maybe the sliding connector is too expensive underwater, especially in sea water.
sea water is too corrosive and too conductive. You could make a single overhead cable and use sea water as your return work. However it wouldn't be practical since ships multiple stories tall need to pass under the wire (and draw a lot of power), while also tiny fishing boards that couldn't even get a pole that high.
The same problem with height would also be an issue for the underwater thing. Quick googling suggests a very large container ship might have a draft of 16-17m when fully loaded. Probably you want the catenary at 20m depth then. How does a small get their pantograph (or whatever you'd call it) down to that depth, and then move forwards without the pantograph sticking 20m down creating a huge amount of drag. Not to mention how do you make the connection between the pantograph and the catenary in the (conductive) sea water?
Make the cable AC and the "pantograph" a (water tight) transformer that glides around the cable. I can't see any other way - DC is not going to work.
Just looking at a couple problems:
> Probably you want the catenary at 20m depth then. How does a small get their pantograph (or whatever you'd call it) down to that depth,
Does the connection from the 'pantograph' to the boat need to be rigid? Use a cable? Maybe it's not for the smaller boats which can't handle a 20m (probably more like 40m for the angle and slack) cable, but also need less power and thus pollute less.
> and then move forwards without the pantograph sticking 20m down creating a huge amount of drag
Presumably, the catenary's route would be cleared of obstructions - maybe even on a frame elevated over the floor, maybe at relatively constant depth - or do I misunderstand? Would a 40m cable cause that much drag? Obviously the pantograph would have to be low friction and highly reliable.
I had always imagined a system of autonomous submarines that function as tugboats along popular routes and then container ships would just function as barges that are hauled by these autonomous submarines. These submarines recharge their batteries automatically by docking to underwater charging stations.
The maintenance of these power points would be astronomical, even if the basic theory could work, which I'm not 100% sure of. You'd have a single high-voltage cable, a pickup pantograph that wraps around the cable acting like a transformer that wheels along the cable, and AC current in the cable with the water itself being the ground reference. I can't imagine any other way it could work.
You don’t need that - if you’re doing short routes you can push enough power into batteries during docking for the next voyage.
Example (7 minute charge time):
https://global.abb/group/en/technology/did-you-know/maid-of-...
I wonder how that expense compares to just building a catenary electric rail bridge and skipping the boat entirely.
Interesting. Generally, waterborne freight is far cheaper than rail. Also, at least sometimes you might need to transfer between modes - ship to rail then rail to ship. But with the underwater catenary solution now we're talking about new infrastructure (not to mention R&D, etc.).
As a sort of transitive analysis: Standard waterborne energy costs are included in the superior pricing of waterborne freight compared to rail. If the underwater catenary solution is competitive to standard waterborne energy costs, it beats rail easily. If the underwater catenary is not competitive, it has no value anyway.
It could still have value if we price in, as we should, the externality of GHG output. THe underwater catenary could reduce GHG output in busy waterways by powering boats that don't have batteries.
In addition to the practical challenges, this would also be highly vulnerable to sabotage.
I suspect the batteries end up cheap enough to make this not worthwhile. If not today, then certainly soon.
> Question is can they get enough power to be useful. Marine diesel engines are very fuel efficient, fuel oil is very energy dense, and they need to run for a long time.
Washington State Ferries refit one of their largest ferries (190-car capacity) as a hybrid recently. They replaced two diesel engines with batteries, leaving the other two engines in place. This provides for significant fuel savings. When shore charging is implemented, fuel use will be reduced even more.
I imagine there are also uses where batteries fully replace engines. I've got a tiny boat for casual fishing, you tend not to use the engine that much, and electric propulsion is likely quieter and can probably modulate to slower speeds which could replace a separate electric trolling motor.
So, what does the article say? Do electric ships dream of Android batteries?