I think all-electric is a stretch goal. Start off with replacing all of the electric loads on a container ship with batteries.
I’m going to rule-of-thumb it and say 10% of a cargo ship’s energy load is electrical. It’s better to quickly convert 100% of cargo ships to hybrid operation than getting 10% of cargo ships to become 100% electric.
The least efficient part of any ship is turning mechanical energy into electrical, so just leave alone the mechanical part (thrust) for now.
(It’s an old idea of mine that never happened: a kit that could turn any ICE vehicle into a hybrid. More and more loads are becoming electrical instead of mechanical, e.g. electric cooling pumps, electric power steering pumps, electronic transmission, electric hvac, in addition to what was always electric: fuel pump, lighting, control systems).
THIS, but even more so. Electric ships sound cool, but shipping is giga-scale global infrastructure. The mines, battery factories, electric motors, dockside equipment, etc. needed to do this at scale don't exist. If they did, the national power grids sitting behind most major ports could not reliably take the additional load.
So, yes, start small. As in: "Here is one self-contained, mostly self-managing battery, inside one cargo container. We'll modify the electrical system on one ship, so that this battery can connect to it, and looks (electrically, and to the ship's control systems) like one extra generator in the engine room. Once we see how well that works, and fix round 1 of bugs and crew training issues, then we'll try to scale up to 10 ships."
> The least efficient part of any ship is turning mechanical energy into electrical
Electrical generators can reach 90+% efficiency at turning mechanical energy into electricity. Did you mean to claim turning chemical energy into electrical?
Good idea. There are these containerized iron salt batteries now that energy companies use to help with renewable energy storage (or at least plan to). Maybe loading a few of those instead of cargo containers could already take care of most of a ships electricity needs - and for recharging you can just load/unload them anywhere like regular containers.
Hybrids, as with cars, provide the most benefit when you can run the engine at its sweet spot more often.
I believe some cargo ships have had relatively tiny batteries for a long time, for port maneuvering where the engine is throttled way down. To prevent pollution they now often are forced to plug in when in port too. So I'd guess this is already just going to happen as battery costs reduce and pollution controls and costs rise, but maybe won't have a big impact on long voyages, though every little bit helps.
The other big play in this space is green ammonia, but similarly early moves are to just burn it in modified diesel engines. Longer term they can electrify with fuel cells.
And obviously those two can work together as Fuel Cell vehicles are basically hybrids with the same drive trains as electric vehicles, just smaller batteries.
A generator or an electric motor don't have a particularly low efficiency or don't wear much? Hybrids happened in locomotives and ships way before cars. Many ships have diesel engines turning generators and then have electric motor propulsion.
You can replace all 23 MW (consisting of 20 MW propulsion and 3 MW electrical) on one ship with batteries + propulsion motor.
Or you can replace just the 3 MW pure electric part with batteries, getting rid of the auxiliary motors and their generators, doing it on 8 ships.
In the latter case you don't need the one propulsion motor, that's true, so it might be somewhat better.
I would start with smaller ships and shorter distances and build from there.
https://zeroemissionservices.nl/en/homepage/ seems to work for short distance inland shipping (‘seems’ to because from what I can tell, they only have a single customer with a single ship, making it more like a demonstrator)
> a kit that could turn any ICE vehicle into a hybrid.
Doable but unpractical in many situations. Internal combustion engine based vehicles are usually a lot heavier than their electric-born counterparts, so their performance would suffer.
Nuclear ships and intercontinental renewable connections can fulfill all energy needs [1] [2] . Nuclear ships can be flexibly deployed to supply power anywhere in the world if there is an emergency. It is unlikely we'll have low power production worldwide at the same time. A small fleet can address a range of concerns.
Better yet, they can carry cargo, 40% of shipping, that is 4.5 billion tons out of the 11 billion tons of total maritime shipping is fossil fuels. [3]. We could have 40% of ships fleet as nuclear ships instead of carrying fossil fuels. If we have the tech to have 40% fleet nuclear, why not make it 100%? There are hundreds (or thousands?) of ships and they can carry cargo as well as supply power when docked. Of course, we have to add PowerDocks at ports and a connection from port to the grid.
Ships use the dirtiest fuel. Large ocean-going ships tend to use bunker fuel, the world’s dirtiest diesel fuel – a toxic, tar-like sludge that usually contains 3,500 times more sulphur than the diesel used for cars.[4]
How about a wind-powered boat powered completely without any batteries or oil at all? Let's call it... a sailboat. Are we just going back in time to when sail-powered ships powered commerce? Of course a sail-powered container ship might not be as viable, but I'd love to see a 16-masted sailing behemoth. The Wikipedia article about the Thomas W. Larson makes for interesting reading: https://en.wikipedia.org/wiki/Thomas_W._Lawson_(ship)
New ship designs are starting to use wind energy to reduce the amount of fuel consumption.
It doesn't look like traditional sails, but large spinning rotors that interact with the wind to propel the ship forward. It's called the Magnus effect.
This link has more info on it including some of the challenging issues of actually implementing it on large commercial ships.
I wonder if a series of small robotic tugboats could take turns hauling a container ship across oceans. As their battery wears down, another swaps in place. They could recharge at nearby fixed solar/wind floating platforms, or undersea cable recharge points.
I have been predicting this for the past few years. Batteries shaped as shipping containers with container ships replacing spent batteries on shipping ports they visit is the future for shipping.
Has anyone thought of large rafts of floating solar panels being towed behind a ship? Given the massive surface area of the ocean I wonder if a few football field sized floating solar panels can recharge the batteries during the day time.
Large container ships are already larger than football fields. As in 61.5m wide and 400m long, though not a rectangle they are surprisingly boxy. You might get 4MW in ideal conditions and average a little over 1MW over the day, but those engines are putting out 58MW, these ships need a lot of power 24/7.
Remember for scale those 20,000 little boxes stacked up are the exact same thing you see semi trucks carrying.
I calculated it out once. The issue is container ships need MASSIVE amounts of energy to move.
As for windmills on the ship... well... sails are a thing we've used for generations :D No reason to convert mechanical energy into electric energy back into mechanical energy.
A few football fields would cause a lot of water drag and also probably not even be enough power. A solar panel is about half a kW, and I’m guessing a big ship like that will take upwards of 80 to 100 MW normally, so you need like 160k to 200k panels.
Great idea, powering a boat with wind. If only someone had thought of that sooner!
Less facetiously, it's usually better to use cylindrical rotating sails (which need power, but far less) or kites. Combined with solar could be an interesting prospect though.
Drag. If you really wanted to do only green shipping, you could have these pads sprinkled across the Atlantic/Pacific, and have boats pull up them to charge up so they can make it to the next pad and hop across the ocean.
Ships move such long distances that batteries will be very expensive and will eat a large proportion of the useful load. Ammonia fuel cells, or, as stopgap, even ammonia burned in diesel engines could be a much better fit.
A nuclear plant dumps a lot more than 30 MW of waste heat into its adjacent body of water. Is that a problem?
Power grids can be upgraded, and a grid-connected battery that can send 300 MW in the other direction during occasional supply shortages is actually really good for grid stability. In that case the ship sells some power at lucrative rates (maybe $1k/mWh?), then recharges later at night after the demand peak.
Bunkering (the process of loading fuel) already takes hours and often requires a rendezvous with a tanker ship at sea, so it's not like ships aren't already inconvenienced by their need to acquire energy.
I'm in the anti-nuclear camp. Mainly because I think the inertia around current consumption patterns is too strong to overcome, so adding a lot of nuclear to the mix would make things a lot more dangerous without making things much better.
This is how I think about the danger of nuclear power. Imagine a really safe nuclear power plant. How often will it fail? Let's say, once every 100,000 years. Assuming this probability is uniformly distributed over the 100,000 year time period, it has a 1/100,000 chance of failing in any given year. A failure seems pretty unlikely. But, there are something like 450 operating nuclear power plants in the world. The chance of a single power plant failing in a year is then 1 - (99,999/100,000)^450 which is around 0.5%. That's starting to look a lot more likely now. After 30 years, there is a 78% chance of a nuclear power plant failing somewhere on Earth.
Now what's even more interesting is if you look back on historic nuclear power accidents at INES level 6 or higher. 1957 - Kyshtym disaster, 1986 - Chernobyl, 2011 - Fukushima. And of course there have been other close calls (e.g. Three Mile Island). The cadence of these accidents seems to match the data from the thought experiment above.
This is one of the endless physics defying articles implying 'acceleration' towards a fantasy all-electric future. Batteries are really heavy and will be exhausted of power very quickly by the continuous load from underwater propellor propulsion.
A small nuclear reactor powered boat would work but the idea of battery powered container ships is specious at best.
Lithium iron phosphate batteries [1] do not use any cobalt and are becoming widespread in battery electric vehicles. Cheaper but less power and energy dense - worth it trade off. Similar calculations would likely apply for shipping.
Can we just skip the inefficient electric market phase all together? It's not gonna last and its not any cleaner than fossil fuels so stop kidding yourselves... The military already uses nuclear power for their ships why not the cargo ships?
is a nuclear powered ship really that much more efficient? The aircraft carrier design goals isn't to make a lightweight, large carry capacity vehicle with low maintenance costs, so i don't see why those designs would fulfill a commercial shipping need.
[+] [-] Scoundreller|3 years ago|reply
I’m going to rule-of-thumb it and say 10% of a cargo ship’s energy load is electrical. It’s better to quickly convert 100% of cargo ships to hybrid operation than getting 10% of cargo ships to become 100% electric.
Edit: this paper says that electric loads are 17% of energy on a medium sized cargo ship: https://www.researchgate.net/publication/335751506_STUDY_ON_...
The least efficient part of any ship is turning mechanical energy into electrical, so just leave alone the mechanical part (thrust) for now.
(It’s an old idea of mine that never happened: a kit that could turn any ICE vehicle into a hybrid. More and more loads are becoming electrical instead of mechanical, e.g. electric cooling pumps, electric power steering pumps, electronic transmission, electric hvac, in addition to what was always electric: fuel pump, lighting, control systems).
[+] [-] bell-cot|3 years ago|reply
So, yes, start small. As in: "Here is one self-contained, mostly self-managing battery, inside one cargo container. We'll modify the electrical system on one ship, so that this battery can connect to it, and looks (electrically, and to the ship's control systems) like one extra generator in the engine room. Once we see how well that works, and fix round 1 of bugs and crew training issues, then we'll try to scale up to 10 ships."
[+] [-] WJW|3 years ago|reply
Electrical generators can reach 90+% efficiency at turning mechanical energy into electricity. Did you mean to claim turning chemical energy into electrical?
[+] [-] awiesenhofer|3 years ago|reply
Article with an image:
https://www.technologyreview.com/2022/02/23/1046365/grid-sto...
[+] [-] ZeroGravitas|3 years ago|reply
I believe some cargo ships have had relatively tiny batteries for a long time, for port maneuvering where the engine is throttled way down. To prevent pollution they now often are forced to plug in when in port too. So I'd guess this is already just going to happen as battery costs reduce and pollution controls and costs rise, but maybe won't have a big impact on long voyages, though every little bit helps.
The other big play in this space is green ammonia, but similarly early moves are to just burn it in modified diesel engines. Longer term they can electrify with fuel cells.
And obviously those two can work together as Fuel Cell vehicles are basically hybrids with the same drive trains as electric vehicles, just smaller batteries.
[+] [-] Gravityloss|3 years ago|reply
You can replace all 23 MW (consisting of 20 MW propulsion and 3 MW electrical) on one ship with batteries + propulsion motor.
Or you can replace just the 3 MW pure electric part with batteries, getting rid of the auxiliary motors and their generators, doing it on 8 ships.
In the latter case you don't need the one propulsion motor, that's true, so it might be somewhat better.
[+] [-] Someone|3 years ago|reply
https://zeroemissionservices.nl/en/homepage/ seems to work for short distance inland shipping (‘seems’ to because from what I can tell, they only have a single customer with a single ship, making it more like a demonstrator)
[+] [-] b112|3 years ago|reply
"But I'm helping the environment!", they say.
Edit: just realised this may seem snarky. It is just that sometimes, this is the end result I expect, regardless of legit effort to help things.
[+] [-] fdsafdsfdsa|3 years ago|reply
I think you meant "most".
The least efficient step is converting chemical energy into mechanical energy.
Given the cheapness of fuel oil and geneator sets, and the expense of batteries, what possible financial argument is there for doing this?
[+] [-] squarefoot|3 years ago|reply
Doable but unpractical in many situations. Internal combustion engine based vehicles are usually a lot heavier than their electric-born counterparts, so their performance would suffer.
[+] [-] newsclues|3 years ago|reply
[+] [-] thelastgallon|3 years ago|reply
Better yet, they can carry cargo, 40% of shipping, that is 4.5 billion tons out of the 11 billion tons of total maritime shipping is fossil fuels. [3]. We could have 40% of ships fleet as nuclear ships instead of carrying fossil fuels. If we have the tech to have 40% fleet nuclear, why not make it 100%? There are hundreds (or thousands?) of ships and they can carry cargo as well as supply power when docked. Of course, we have to add PowerDocks at ports and a connection from port to the grid.
Ships use the dirtiest fuel. Large ocean-going ships tend to use bunker fuel, the world’s dirtiest diesel fuel – a toxic, tar-like sludge that usually contains 3,500 times more sulphur than the diesel used for cars.[4]
[1] https://en.wikipedia.org/wiki/Australia-Asia_Power_Link
[2] https://www.power-technology.com/projects/morocco-uk-power-p...
[3] https://qz.com/2113243/forty-percent-of-all-shipping-cargo-c...
[4] https://www.theguardian.com/uk-news/2017/may/18/dirty-diesel...
[+] [-] rexreed|3 years ago|reply
[+] [-] mediaman|3 years ago|reply
It doesn't look like traditional sails, but large spinning rotors that interact with the wind to propel the ship forward. It's called the Magnus effect.
This link has more info on it including some of the challenging issues of actually implementing it on large commercial ships.
https://www.marineinsight.com/naval-architecture/flettner-ro...
[+] [-] nickhalfasleep|3 years ago|reply
[+] [-] spankalee|3 years ago|reply
Seems like a kite + battery combination could be quite effective.
[+] [-] xbmcuser|3 years ago|reply
[+] [-] belltaco|3 years ago|reply
Also, what about windmills on the ship itself?
[+] [-] Retric|3 years ago|reply
Remember for scale those 20,000 little boxes stacked up are the exact same thing you see semi trucks carrying.
[+] [-] cogman10|3 years ago|reply
As for windmills on the ship... well... sails are a thing we've used for generations :D No reason to convert mechanical energy into electric energy back into mechanical energy.
[+] [-] jasonjayr|3 years ago|reply
So like, sails? :)
Iirc there has also been wind-driven electrical generating devices on boats too.
[+] [-] gotmedium|3 years ago|reply
See windmill ships for more on the second question > https://en.m.wikipedia.org/wiki/Windmill_ship
[+] [-] ok_dad|3 years ago|reply
[+] [-] Schroedingersat|3 years ago|reply
Great idea, powering a boat with wind. If only someone had thought of that sooner!
Less facetiously, it's usually better to use cylindrical rotating sails (which need power, but far less) or kites. Combined with solar could be an interesting prospect though.
[+] [-] googlryas|3 years ago|reply
[+] [-] 6t6t6t6|3 years ago|reply
You mean, like sails?
[+] [-] markdestouches|3 years ago|reply
[+] [-] Gravityloss|3 years ago|reply
https://techxplore.com/news/2021-03-world-high-temperature-a...
Absence of cheap bunker oil would though maybe motivate for more efficient designs / operations. Ie slowers speeds, variable schedules and all that.
[+] [-] mikewarot|3 years ago|reply
Assume 90% efficiency - that means dropping 30 Megawatts of heat into the water in port. That could be a problem.
Also - 300 Megawatt single point loads? What's that going to do to grid stability?
[+] [-] chrismartin|3 years ago|reply
Power grids can be upgraded, and a grid-connected battery that can send 300 MW in the other direction during occasional supply shortages is actually really good for grid stability. In that case the ship sells some power at lucrative rates (maybe $1k/mWh?), then recharges later at night after the demand peak.
Bunkering (the process of loading fuel) already takes hours and often requires a rendezvous with a tanker ship at sea, so it's not like ships aren't already inconvenienced by their need to acquire energy.
[+] [-] Tade0|3 years ago|reply
[+] [-] _hypx|3 years ago|reply
[+] [-] Traubenfuchs|3 years ago|reply
[+] [-] ianai|3 years ago|reply
[+] [-] ok_dad|3 years ago|reply
It’s also not even a little economical.
[+] [-] atwood22|3 years ago|reply
This is how I think about the danger of nuclear power. Imagine a really safe nuclear power plant. How often will it fail? Let's say, once every 100,000 years. Assuming this probability is uniformly distributed over the 100,000 year time period, it has a 1/100,000 chance of failing in any given year. A failure seems pretty unlikely. But, there are something like 450 operating nuclear power plants in the world. The chance of a single power plant failing in a year is then 1 - (99,999/100,000)^450 which is around 0.5%. That's starting to look a lot more likely now. After 30 years, there is a 78% chance of a nuclear power plant failing somewhere on Earth.
Now what's even more interesting is if you look back on historic nuclear power accidents at INES level 6 or higher. 1957 - Kyshtym disaster, 1986 - Chernobyl, 2011 - Fukushima. And of course there have been other close calls (e.g. Three Mile Island). The cadence of these accidents seems to match the data from the thought experiment above.
[+] [-] survirtual|3 years ago|reply
[+] [-] arriu|3 years ago|reply
[+] [-] olivermarks|3 years ago|reply
A small nuclear reactor powered boat would work but the idea of battery powered container ships is specious at best.
[+] [-] pfdietz|3 years ago|reply
[+] [-] dr-detroit|3 years ago|reply
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[+] [-] biophysboy|3 years ago|reply
[+] [-] SECProto|3 years ago|reply
[1] https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
[+] [-] option|3 years ago|reply
[+] [-] Schroedingersat|3 years ago|reply
That will work out great.
[+] [-] iinnPP|3 years ago|reply
[+] [-] 12many|3 years ago|reply
[+] [-] greedo|3 years ago|reply
[+] [-] chii|3 years ago|reply
[+] [-] unknown|3 years ago|reply
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