Nobody said it was unique to an electric car. If you put a giant battery in the back of a gasoline powered truck and drove it to your friends house, you could say you were transporting energy. Or if you put a tank of gas for that matter. Seems very similar.
> I guess if electric cars make sense then this also makes sense for transporting energy?
I don't see how that follows. The point of a electric car isn't to transport the electricity, it's to transport matter. There's no shortcut here: the only realistic way (short of Star Trek transporter beams) we can get the cargo from point A to point B is by physically moving it.
In contrast, we already have other ways to transport energy which work quite well. It's hard to see how this absurd concept could possibly be competitive with them.
I'm sure there are edge cases where putting batteries in ships can make sense. Let's assume the following is true:
1) Two islands exist relatively close to each other.
2) Both have enough wind power to meet demand on windy days.
3) Deep waters, strong tidal currents, tsunami risk or some combination make power lines between the islands somewhat expensive or unreliable.
4) Battery storage is required to meet demand on days with little wind.
5) Storing these batteries on ships is not significantly more expensive than storing the batteries on land. (Maybe real estate prices are high, regulations are stricter on land, etc.)
In such a case, it may be more economical to move the ship holding the batteries than to set up cables intended just for low wind periods. And if there are many islands involved, an ecosystem of ships may scale better than cables, for instance if demand is seasonal or varies for other reasons.
Basically, these are similar reasons to why LNG regasification ships exist, instead of just building fixed land-based facilites where needed.
Tangentially, the book The Vital Question is fascinating: it explains how life on earth is basically just proton-moving machines with flair (and how such machines could have come to evolve in the first place).
When you charge a battery you are pushing electrons from one chamber in the battery to another. A discharged battery is like two tanks of water at equal levels, charging is like pumping water from one to the other so one has a higher level and thus potential energy.
My guess would be that pretty much everybody knows that this mental model is wrong, which is why the author considered it appropriate to jokingly play naive, because just calling it "bizarre" felt too weak.
"Why not just put down an underwater cable? That's a fine question. PowerX points out that Japan is surrounded by deep seas, and prone to earthquakes, and says in a press release that "the ship-based solution resolves issues such as long downtime from undersea cable malfunctions and repairs, as well as the high costs associated with ultra-high voltage connections and substations."
Coming from the owners of a battery factory, also sounds a bit like a Sim City news ticker message: "Pineapple-based economy a no-brainer: President of the World Pineapple Trade Federation".
Then again, they could well be right on a one-ship basis and maybe that's all they need, and this needs less capital expenses like, say, a hydrogen handling terminal at each end.
That doesn't make a ship a viable alternative by itself. And there are plenty of undersea cables within Japan, including power cables.
The solution would seem to be to generate power in Japan not to transport it there by such bizarre (I agree with the title here) method. But let's reserve judgment and see how it plays out in practice, I'm going to watch this one just to see how real life matches my intuition about this project.
OK guys hear me out. Instead of building power cables let's build giant undersea pneumatic tubes and use those to deliver charged batteries from one island to another. That idea should be worthy of a few million in funding, right?
Put wheels on the capsules and make it an electric pickup truck with the batteries on the bed, make the tube 10 feet across and I think I know the company for you!
I wonder how hard it'd be to build neutral buoyancy power cables that could float significantly above the seafloor. Of course you're still going to get wrecked by trawlers & anchors, potentially. UT man, I just have such a hard time seeing this as comparatively competitive.
You just lay the lines on the seafloor (cheapest), lay more than you need as redundancy, and then when some get broken by earthquakes you use a cable repair ship to repair them.
It's pretty standard stuff, and most cables last year's between breaks.
I'd absolutely love to do DD on this project. It has all kinds of interesting bits to research. On the assumption that they have done their homework there must be something non-obvious that they know that outsiders don't.
I mean it’s a press release. Those don’t cost anything.
The only application of this that seems half feasible is maybe some kind of post-disaster recovery where for whatever reason you’ve ruled out using a generator.
Even then you'd probably be better off shipping a mixed load of diesel trucks and large generators.
Even the larger version doesn't make a whole lot of sense, you'd be looking at keeping the ship in port for quite a while unless those batteries are going to be charging and discharging at very high rates but that would shorten their life (and hence the number of trips). They are aiming to do 'short runs' only (100 km is mentioned in the article but the economic range is a bit larger) which makes it even more dicey economically.
Their transportation costs per KWh as quoted in the article exceed current generation costs by a factor of three already. 214 MWh is a proverbial drop in the bucket on grid scale and even 10x isn't all that much, and you can only deliver power if you have enough of those vessels to guarantee overlap at the destination or you're going to have to deal with outages.
Maybe they plan to swap batteries in and out of the ship, have a rotating set of ten (or whatever) batteries, one discharging, eight charging, load the tenth with a crane, swap out for the discharged one, cycle through...
There are lots of grid scale battery companies, A123 was one, that were (still are?) Building giant battery packs into shipping containers as a way to store and deliver energy to the power grid during high/low cycles. One could conceive of just using those and loading and unloading them just like standard containers on a ship.
Sources say 13.7 MWh of energy per ton of LNG. This is in BTUs so at 60% efficiency of a fairly modern gas plant would yield 8.2MWh of electricity generation potential per ton. The largest LNG carrier carries over 80,000 tons of LNG https://en.m.wikipedia.org/wiki/LNG_carrier
So that would work out to 656 GWh of electric generation potential for a full load of the largest LNG carrier. More than 2000x the capacity of the battery carrier.
Answering the original question, it's about 10-20x as much usable energy for the oil. So if there's a wind farm 5% of the distance than an oil farm, the cost of the ship part is a wash.
LNG is 20x the energy for a given volume than Lithium ion batteries. It's 50-60x as much energy for a given mass. The mass is the limiting factor for ocean transportation.
Also false. LNG carriers are volume limited. Hence Q-Max vessels carrying about 100,000 tonnes vs bulk carriers of similar length carrying 400,000 tonnes.
Also I said useful energy. Depending on application, electricity is 1.5-5x as useful per joule.
Have you considered not just reaching for the stupidest possible lie on every occasion?
LNG carrier are volume limited, a freighter carrying bulk lithium ion batteries is mass limited.
Have you considered rethinking whether you misread a parent comment before accusing them of "reaching for the stupidest possible lie"? Let's re-read my comment:
> LNG is 20x the energy for a given volume than Lithium ion batteries. It's 50-60x as much energy for a given mass. The mass is the limiting factor for ocean transportation.
Liquid natural gas is less dense than water, so of course ocean transportation of it is not mass limited. Did it really no occur to you that I was referring to transportation of lithium batteries?
Anyway if you doubt that ocean transportation of lithium batteries is mass limited here's some math for you:
TEU to volume conversion is inexact, but the most common 20' x 8' x 8'6" container is 33.2 cubic meters. This yields 33.2 * 24K = 796800 cubic meters for our Evergreen Ace.
The density of lithium ion batteries is more complicated. Sources say a 18650 battery weights 45g. The dimensions an 18650 are 18mm diameter base and 65mm length, yielding 16.54 cubic centimeters. So mass per cubic meter is 2720Kg, or 2.72 tonnes.
If we filled the Evergreen Ace with containers full of lithium ion batteries we'd have 2.72 tonnes per cubic meter * 796800 cubic meters would yield 2,167,296 tonnes versus our DWT of 235,579. We're almost an order of magnitude over weight if we fill out ship to the brim with batteries. Sure, there's nuances like packing efficiency (there's gaps between battery cells), but transportation of lithium ion batteries are overwhelmingly mass limited
> Liquid natural gas is less dense than water, so of course ocean transportation of it is not mass limited. Did it really no occur to you that I was referring to transportation of lithium batteries?
You were comparing LNG by mass to batteries by mass.
Now you're trying to pretend I was comparing volume to volume rather than a ship full.
So I guess the answer is no. You've never considered saying anything in good faith.
> A sensible 'normalised' comparison might be energy carried per displacement kilotonne or some such.
Defrost explicitly specified mass, "per displacemet kilotonne" To which you responded:
> Answering the original question, it's about 10-20x as much usable energy for the oil
10-20x is the ratio of energy density by volume, not mass.
I'm going to extend assumption of good faith, as it's easy to forget that there's two different measures of energy density. But yes, you did respond to someone asking about relative energy density by mass with the relative energy density by unit of volume. And the energy density by mass is indeed the limiting factor when shipping bulk lithium ion batteries, so this is a misleading (but probably not bad faith) figure to cite.
> No, see I answered the actual question, which is oil. Which is mass limited.
Correct, and then you turned around and gave a figure for the relative energy density by volume, instead of mass (which would be a disparity 3-6x larger). And mass is the limiting factor for bulk shipping lithium ion batteries.
Using current gen batteries, this is a cargo of about 1200t for 240MWh
Oil would be 13000MWh of chemical energy. Or a replacement for 2000-7000MWh of electricity.
It would never be worth transporting electricity from the oil well, but if the option is transporting oil 3000km or transporting electricity from a wind turbine 200km away, the battery-ship is a better use of the ship (but maybe not a better use of the batteries than using a wire).
"Currently named "Battery Tanker X," the prototype won't be going very far. Pushing a vessel through draggy water is a nightmare for battery-powered electric propulsion systems, so the ship's maximum range before it burns through too much battery to make the trip economically feasible is slated at just 300 km (186 miles).
A full production "Power Ark" the same size, says PowerX, might move about 4,190 GWh of electricity annually from renewable sources in Hokkaido to meet demand in Aomori just 100 km (62 miles) away, making use of transmission infrastructure already in place but soon to be abandoned as fossil fuel-based generation capacity is gradually shut down. "
I'm reading a lot of comments seemingly missing these details. Interesting and seems to be useful in Japan's geography that I'm not personally used to thinking about.
What detail of Japan's geography that's supposed to make this viable did you pick up from that text?
Aomori is not some island so remote and isolated they can't possibly run underwater cables to. It's on Honshu. You know, the main island. On the same power grid as Tokio.
"making use of transmission infrastructure already in place but soon to be abandoned as fossil fuel-based generation capacity is gradually shut down. "
From article:
"Why not just put down an underwater cable? That's a fine question. PowerX points out that Japan is surrounded by deep seas, and prone to earthquakes, and says in a press release that "the ship-based solution resolves issues such as long downtime from undersea cable malfunctions and repairs, as well as the high costs associated with ultra-high voltage connections and substations.""
Possibly it works for small remote island or remote offshore wind turbines (depending on cost), but I don't know who want to use it for Hokkaido-Aomori.
The problem with compressed air power storage is the heat generated from the compression process, you never recover that so the losses are such that the efficiency overall is pretty bad
I'd love to see something like this (hopefully smaller scale) used for maritime power. Power shipping itself with some semi-roving large power stores.
Assuming there's an electrified fleet worth serving seeming like a big challenge. It might probably need to be a bit more modestly sized/scoped. But this idea of large mobile batteries keeps being interesting to me.
It would be far better to use the energy locally to disassociate sea water and turn it into hydrogen, then ship the hydrogen.
They're doing this with the sea change ferry in San Francisco. The hydrogen that it runs on will be created from electricity and seawater at the point if use, on a floating fuel barge. It gets even better, they're using fully green hydroelectric energy from Hetch Hetchy reservoir, so the whole chain is about as green as possible, and is really an example for the rest of the world to follow.
The much higher capacity 8000 gross tonne hydrogen carrier can deliver about 1400MWh, after spending 3000MWh filling it up with a bunch of electrolysers then liquifying the hydrogen which you'd have to build a floating platform for.
https://en.m.wikipedia.org/wiki/Suiso_Frontier
It looks like someone took the "Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway" sneakernet idea literally.
81 comments
[ 3.3 ms ] story [ 170 ms ] threadThis is an interesting concept - I guess if electric cars make sense then this also makes sense for transporting energy?
I don't see how that follows. The point of a electric car isn't to transport the electricity, it's to transport matter. There's no shortcut here: the only realistic way (short of Star Trek transporter beams) we can get the cargo from point A to point B is by physically moving it.
In contrast, we already have other ways to transport energy which work quite well. It's hard to see how this absurd concept could possibly be competitive with them.
1) Two islands exist relatively close to each other. 2) Both have enough wind power to meet demand on windy days. 3) Deep waters, strong tidal currents, tsunami risk or some combination make power lines between the islands somewhat expensive or unreliable. 4) Battery storage is required to meet demand on days with little wind. 5) Storing these batteries on ships is not significantly more expensive than storing the batteries on land. (Maybe real estate prices are high, regulations are stricter on land, etc.)
In such a case, it may be more economical to move the ship holding the batteries than to set up cables intended just for low wind periods. And if there are many islands involved, an ecosystem of ships may scale better than cables, for instance if demand is seasonal or varies for other reasons.
Basically, these are similar reasons to why LNG regasification ships exist, instead of just building fixed land-based facilites where needed.
When you charge a battery you are pushing electrons from one chamber in the battery to another. A discharged battery is like two tanks of water at equal levels, charging is like pumping water from one to the other so one has a higher level and thus potential energy.
A medium sized power station is say 300 megawatts.
So if you want to transport this power just a few tens of miles, you probably need a fleet of 10+ ships constantly charging and discharging.
I am very dubious that that works out cheaper than just laying a cable, even through deep water.
"Why not just put down an underwater cable? That's a fine question. PowerX points out that Japan is surrounded by deep seas, and prone to earthquakes, and says in a press release that "the ship-based solution resolves issues such as long downtime from undersea cable malfunctions and repairs, as well as the high costs associated with ultra-high voltage connections and substations."
Then again, they could well be right on a one-ship basis and maybe that's all they need, and this needs less capital expenses like, say, a hydrogen handling terminal at each end.
The solution would seem to be to generate power in Japan not to transport it there by such bizarre (I agree with the title here) method. But let's reserve judgment and see how it plays out in practice, I'm going to watch this one just to see how real life matches my intuition about this project.
It's pretty standard stuff, and most cables last year's between breaks.
The only application of this that seems half feasible is maybe some kind of post-disaster recovery where for whatever reason you’ve ruled out using a generator.
Even the larger version doesn't make a whole lot of sense, you'd be looking at keeping the ship in port for quite a while unless those batteries are going to be charging and discharging at very high rates but that would shorten their life (and hence the number of trips). They are aiming to do 'short runs' only (100 km is mentioned in the article but the economic range is a bit larger) which makes it even more dicey economically.
Their transportation costs per KWh as quoted in the article exceed current generation costs by a factor of three already. 214 MWh is a proverbial drop in the bucket on grid scale and even 10x isn't all that much, and you can only deliver power if you have enough of those vessels to guarantee overlap at the destination or you're going to have to deal with outages.
I wonder who is investing in this project.
I'm not familiar with global sea route, but I'd imagine use cases for <100 mile route by small cargo ship is limited?
Unless the energy density multiplies quickly, it feels more like a vaporware.
They're doing this with the Sea Change hydrogen ferry in San Francisco https://www.sfchronicle.com/climate/article/san-francisco-fi...
Is it prudent to think about a parallel means of energy transfer that works in the immediate aftermath of another scale 9 earthquake and disaster?
https://transportgeography.org/contents/chapter4/transportat...
Is the ratio something like this? 41 to 0.5? 82x?
So that would work out to 656 GWh of electric generation potential for a full load of the largest LNG carrier. More than 2000x the capacity of the battery carrier.
Direct comparison of the largest LNG carrier in existance Vs. early proof of concept "maybe this is worth a shot" vessel isn't especially meaningful.
A sensible 'normalised' comparison might be energy carried per displacement kilotonne or some such.
Also I said useful energy. Depending on application, electricity is 1.5-5x as useful per joule.
Have you considered not just reaching for the stupidest possible lie on every occasion?
> LNG is 20x the energy for a given volume than Lithium ion batteries. It's 50-60x as much energy for a given mass. The mass is the limiting factor for ocean transportation.
Liquid natural gas is less dense than water, so of course ocean transportation of it is not mass limited. Did it really no occur to you that I was referring to transportation of lithium batteries?
Anyway if you doubt that ocean transportation of lithium batteries is mass limited here's some math for you:
The biggest freighter has a volume capacity of 24K TEU and a mass capacity of 235,579 tonnes: https://en.m.wikipedia.org/wiki/Evergreen_A-class_container_...
TEU to volume conversion is inexact, but the most common 20' x 8' x 8'6" container is 33.2 cubic meters. This yields 33.2 * 24K = 796800 cubic meters for our Evergreen Ace.
The density of lithium ion batteries is more complicated. Sources say a 18650 battery weights 45g. The dimensions an 18650 are 18mm diameter base and 65mm length, yielding 16.54 cubic centimeters. So mass per cubic meter is 2720Kg, or 2.72 tonnes.
If we filled the Evergreen Ace with containers full of lithium ion batteries we'd have 2.72 tonnes per cubic meter * 796800 cubic meters would yield 2,167,296 tonnes versus our DWT of 235,579. We're almost an order of magnitude over weight if we fill out ship to the brim with batteries. Sure, there's nuances like packing efficiency (there's gaps between battery cells), but transportation of lithium ion batteries are overwhelmingly mass limited
You were comparing LNG by mass to batteries by mass.
Now you're trying to pretend I was comparing volume to volume rather than a ship full.
So I guess the answer is no. You've never considered saying anything in good faith.
> A sensible 'normalised' comparison might be energy carried per displacement kilotonne or some such.
Defrost explicitly specified mass, "per displacemet kilotonne" To which you responded:
> Answering the original question, it's about 10-20x as much usable energy for the oil
10-20x is the ratio of energy density by volume, not mass.
I'm going to extend assumption of good faith, as it's easy to forget that there's two different measures of energy density. But yes, you did respond to someone asking about relative energy density by mass with the relative energy density by unit of volume. And the energy density by mass is indeed the limiting factor when shipping bulk lithium ion batteries, so this is a misleading (but probably not bad faith) figure to cite.
You jumped to a ship two orders of magnitude larger and then insisted LNG carrying was mass limited, not volume limited.
I did not forget anything, merely pointed out the bizarre attempts to mislead.
Correct, and then you turned around and gave a figure for the relative energy density by volume, instead of mass (which would be a disparity 3-6x larger). And mass is the limiting factor for bulk shipping lithium ion batteries.
That wouldn't have been a ridiculous attempt to mislead.
Using current gen batteries, this is a cargo of about 1200t for 240MWh
Oil would be 13000MWh of chemical energy. Or a replacement for 2000-7000MWh of electricity.
It would never be worth transporting electricity from the oil well, but if the option is transporting oil 3000km or transporting electricity from a wind turbine 200km away, the battery-ship is a better use of the ship (but maybe not a better use of the batteries than using a wire).
A full production "Power Ark" the same size, says PowerX, might move about 4,190 GWh of electricity annually from renewable sources in Hokkaido to meet demand in Aomori just 100 km (62 miles) away, making use of transmission infrastructure already in place but soon to be abandoned as fossil fuel-based generation capacity is gradually shut down. "
I'm reading a lot of comments seemingly missing these details. Interesting and seems to be useful in Japan's geography that I'm not personally used to thinking about.
Aomori is not some island so remote and isolated they can't possibly run underwater cables to. It's on Honshu. You know, the main island. On the same power grid as Tokio.
From article:
"Why not just put down an underwater cable? That's a fine question. PowerX points out that Japan is surrounded by deep seas, and prone to earthquakes, and says in a press release that "the ship-based solution resolves issues such as long downtime from undersea cable malfunctions and repairs, as well as the high costs associated with ultra-high voltage connections and substations.""
Possibly it works for small remote island or remote offshore wind turbines (depending on cost), but I don't know who want to use it for Hokkaido-Aomori.
https://en.wikipedia.org/wiki/High-voltage_direct_current#Co...
Here's more details on the ship and idea behind it:
https://www.prnewswire.com/news-releases/introducing-the-wor...
https://oceanpowergrid.jp/
I think it's a matter of economics and if they can make money on it, which I'm going to to presume it is possible since people are doing this.
Assuming there's an electrified fleet worth serving seeming like a big challenge. It might probably need to be a bit more modestly sized/scoped. But this idea of large mobile batteries keeps being interesting to me.
They're doing this with the sea change ferry in San Francisco. The hydrogen that it runs on will be created from electricity and seawater at the point if use, on a floating fuel barge. It gets even better, they're using fully green hydroelectric energy from Hetch Hetchy reservoir, so the whole chain is about as green as possible, and is really an example for the rest of the world to follow.
https://www.sfchronicle.com/climate/article/san-francisco-fi...
8000 tonnes of 200Wh/kg batteries is 1600MWh.
This is dumb, but hydrogen is much, much dumber.