One of the painful early lessons for the industry was the discovery that minimizing operational costs (particularly fuel and maintenance) trumps every other value. A pioneering containerized shipping company went bankrupt pursuing a high-speed shipping strategy that cost marginally more than low-speed competition.
Edit: Oh, there is a second edition! Updated link.
Edit: replaced unhelpful snark.
And these "sails" are much newer tech...
This one is about tankers, and the other was about bulk carriers.
They are the most important factors in the context of reliably shipping goods from port to port. If there was a sail technology that allowed reliable transit, predictable speeds and times (really slow is OK, a little late is not), and didn't cause an increase in other costs (say, insurance or maintenance), and could move the tonnage involved (up to 40 tons per container multiplied by thousands of containers, or enormous dry goods loads), I suspect it would capture a sizable portion of the market.
Edit: it occurs to me that significantly reducing fuel costs would allow entirely new kinds of loads to be transported and potentially radically alter the world economy. I once saw a chart where the Y axis was price per unit and the X axis was unit density. There was a line on the chart, above which it is economical to ship a good, below which it is not. The top right of the chart had things like electronics - which have been shipped since the dawn of the industry. The bottom left had things unprocessed ore, which have never made sense to ship.
China mines and ships bauxite from Fiji to China.
It is one of the bigger industries in Iceland: https://www.nytimes.com/2017/07/01/us/politics/american-comp...
Some practical considerations come into play - while saving money is good, being able to reach your destination when you say you will is also worth something. With pure wind you lose that control. Deck size is not infinite, so there is a limit to how many sail towers are useful. Tower height also has practical limits before it destabilizes the ship. Handling bad weather is much easier with the on-demand power that comes from engines.
Solar is just nowhere near good enough compared to the needs of a massive ship like this.
Wind would maybe work, but then remember that a turbine would effectively slow you down as you'd be pushing against the air.
If your $ per kWh is something ridiculously low like $0.002 you can economically electrolyze h2o to pure hydrogen.
The surface area of the ship, don't care about that. A 20x20km area of the Mojave desert covered in super low cost PV can provide the power needed.
This is the same economy of scale thing as a solar powered car. If you were to theoretically cover every square cm of a Tesla model S in high efficiency PV, and let it sit in the sun all day, it might take a week or more to collect the 95kWh needed to charge it fully. But if the PV is somewhere else on rooftops or otherwise-useless arid land, connected to the grid, you can plug your car in to a 240V 30A socket in your garage and charge it every day.
This is not nothing. It's roughly as much power as a redlined sports car engine. It might be sufficient to fight the worst ocean currents, since propulsion power scales so frighteningly faster than speed.
It would also make sense, with larger ships, to just implement the nuclear tech we already have.
IANA(nuclear scientist) but I imagine that it has to do with the lack of nuclear engines available for the commercial market, which is due to nuclear technology being restricted by export controls and the like. Keeping nuclear engines and fuel out of the hands of others is much simpler when they're only on military ships with armories and soldiers, basically impossible on unarmed, undefended commerical shipping vessels.
Do correct me if I'm wrong ...
And a sports car is what, 3,000 pounds? A container ship is something like 200,000 tons. I guess they can power a redlining sports car engine when out to sea but not a whole lot else.
A Maersk Triple E has two up-to-30MW-each engines and a design speed of 19 knots. You'd scale down speed by a factor of 12 to achieve 1.6 knots (0.8m/s), and out of that you would get to scale down power by a factor of 144 to meet your ~400kw solar power endowment.
The question is whether you can cross the most powerful currents, and at 1.6 knots you would certainly need to be cognizant of them to stand a chance, but you could ford them in the manner of fording a river: Get pushed downstream a bit, but cross the highest velocity area perpendicular.
The Maersk Triple E and huge bulk carriers are practically worst-case-scenarios for solar, because there's so much ship to displace water under every square meter of solar. A smaller lighter catamaran is likely to find itself with dramatically higher speeds, albeit not linearly higher with hull depth, since a longer waterline is more efficient.
I'm not suggesting this is practical. I think massive nuclear powered cargo ships capable of high speed is a hell of a lot more practical in a post-carbon world. But again: it's not nothing.
A big cargo ship's engine can be 25000kw. The biggest wind turbines (750') generate about 8000kw. So.. three of them? The ship would need to be 1500 feet long just to make room. But the wind isnt constant. Five turbines? Bridges might be an issue.
It's the square-cube law in operation. It also applies to solar. The only application of solar mounted on a transportation vehicle that makes any sense is those ultra-light unmanned planes that cruise above 60,000 feet.
I picture a small-ish shipping ship, say something moving 20 or 30 containers only, fully autonomous (100% crewless) with sails and solar only powering it. Solar electric motors handling the near-land operations and "not enough wind" conditions, sails otherwise. If you had autonomous loading and unloading, you would have zero variable/operational cost.
I am certain there are very good reasons this would never work, but I still love the idea.
Crews are cheap. Ships' masters are not.
Part of me starts to wonder now about building boats that are more resilient, but then I remember that salt water is terrible and surely by now someone would have if it were possible, since we spend so much money on humans doing that maintenance!
The number can rise further with more complex cargo.
I think it will do to shipping what two engine, midsized passenger jets (A350/787) are doing to air travel: connect directly between small ports anywhere, instead of using very large ports as hubs. FedEx/UPS could have sea terminals anywhere, possibly automated.
Global shipping will only grow and I don't see a driver for air freight prices to drop enough so that things are truly international (e.g. buy a fridge from AliExpress).
I think it needs to happen, and will happen.
As for very good reasons why this would never work, sometimes that is beside the point. I am not in the running to redesign trade and power on my own terms, but sometimes I can flush out assumptions that don't need to be held.
Im imagining an LED throwie type big magnetic thing with gps RX and TX, and a satellite uplink. Cruise by the autonomous ship on a jetski near a port, thrown the magnet thing on, jetski away, disrupt from afar once the boat is out at sea.
For a while in 1930's small Åland had the largest sailing fleet in the world.
So you can use sails to help, but if you rely on them you might be late.
Example without sails: https://en.wikipedia.org/wiki/MSC_Napoli:
”during European windstorm Kyrill, severe gale-force winds and huge waves caused serious damage to Napoli's hull, including a crack in one side and a flooded engine room
the earlier grounding in 2001 did not contribute to the loss”
That ship was 62,000 tons. That’s not huge by today’s standards, but not small either.
Edit: It is even likely that the chase of lower operational cost played a major role in the current oversupply of capacity (thanks to a glut of mega sized ships)
I’m not convinced that this is static — as far as I can see it should depend on the prevailing rate of interest. The more a company pays in interest on a loan, the faster it should want to realize its investment (which doesn’t happen by goods sitting in a container).
I’m not sure what the equilibrium interest rate is, exactly, but at some level of interest it should become cheaper to ship the goods faster, since you will save more in interest payments than the extra you pay for shipping (due to your investment becoming operational sooner, allowing you to pay back the loan).
Whatever the reason, I'm sure everyone who uses a bridge in SF is happy about this.
I'm curious of what will be the results.
Given that they soon expect to be spending $5 billion/year on fuel for 800 ships, fuel spend is a bit north of $6 million/year for an "average" ship. But size seems to vary widely (they note that only the 80 of their largest ships are being considered for these sails).
At an installation cost of $2 million, saving 10% of an "average" ship would return 600k per year, or a 3.5 year paypack, which seems well worth doing where possible. And they'll obviously get better than that on their 80 largest.
Not a magic bullet by any means, but certainly seems worth using.
I've seen it mentioned boats/ships using electric assist will also be another catalyst for battery tech integration, fuel costs on those large ships are always a topic.
Bolt on solutions that are affordable with quick turn around on investment.
- The cost needs to be fairly easy to measure
- Some degree of competition in the industry exists (otherwise the capital could be used to increase revenue or acquire small potential rivals before they're too large to afford, among other higher return places to spend the capital)
- The industry is mature and sources of larger savings already exhausted
- Prospect for some future much bigger savings small (or at least not in conflict with the current effort)
- Prospect for the industry as a whole very good (in a shrinking market, 10% savings becomes lower priority than selling off assets quickly enough at high enough cost without subsidizing a competitor or startup)
- Industry consolidated enough (or capital costs of the improvement low enough) to finance the upfront cost
I always thought sails were partially defined by being passive. I wonder why these aren't called "rotor fans" if they're electrically driven?
Is there anywhere it's discussed when rotors are expected to outperform normal fans? They seem to be used only on large ships, but I can't see a first-principles explanation for that.
These rotors create lift in a forwards direction from the wind blowing across them, a bit like having a fixed wing pointing up.
> No. Literally the same point, but in different words and with a feel of authority.
You should consider using words other than "No" if you agree with the point.
Years ago on /. I saw a post about how wales bumps on the leading edges of their fins/flippers were to increase/modify the eddies around their fins in such a way as to provide them more thrust (or something, it's been years since I read the article) - and I was curious what it would look like to have helicopter blades with leading edge bumps on them similar to wales...
So, I'd like to see what dimples both convex and concave would have on the surfaces if these - like a golf ball.
Also, if you have never done it, take a cylindrical plastic cup and, in a bathtub full of water spin the cup as hard as you can on the surface of the water - like a top - and see how long you can get it to stand up. Kids like this trick.
I always thought it would be interesting to have a barge like flat boat on top of several cylindrical feet like floats, which can spin rapidly along the Z access and use it as thrust.
They explain that in the article, and the fact that it newer tech and lighter columns to get a net benefit.
Having grown up in France, I knew about Cousteau's Alcyone (it was a big deal at the time) and had been wondering why it hadn't been used more since then.
It’s not a turbosail. Turbo sails don’t rotate..
> These are known as Flettner rotors after the German engineer Anton Flettner who invented them and made the first rotor sailing ship in 1924, with one sailing one across the Atlantic in 1926 - and they are not turbo sails. They have generally been in disuse as it has been deemed that the energy expended in propulsion by Flettner rotors was higher than that for propellers - perhaps it seems with modern materials, wind monitoring and computer assisted controls this has been tilted to the favor of Flettner rotors. Flettner also invented trim tabs which any large power boat operator knows very well.
> An interesting note, Flettner was considered so valuable to the Germans in WW2 that Heinrich Himmler, the head of the Gestapo saw to it that Flettner's Jewish wife was escorted to Sweden for her safety for the duration of the war.
That's nice and all but he still helped the nazis with military research while many of his colleagues fled, Einstein included.
Together with using LNG, periodically cleaning the bottom of the ship, slower speed and connecting to electric grid while in harbor the CO2 emissions are down significantly.
The best way to reduce energy consumption for a ship is to reduce the speed and make thinner ships. This is the new trend in shipbuilding. New cargo ships optimized for slow speed don't have the bulbous bow because it does not increase efficiency in lower speeds.
Turku - Stockholm, actually.
> The best way to reduce energy consumption for a ship is to reduce the speed and make thinner ships.
Do you mean thinner as in narrower, or thinner materials to save weight? If you mean narrower, I've understood bigger ships tend to have a length/width ratio of about 6:1, as a rule of thumb compromise between seakeeping ability, fuel consumption, cargo space etc. Do you have some more information about design tradeoffs going into such narrower ships?
> New cargo ships optimized for slow speed don't have the bulbous bow because it does not increase efficiency in lower speeds.
Oh, interesting! Any links for further reading on this topic?
Hopefully someday almost all ships have a mix of these things + maybe run on algae-based advanced biofuels or something like that.
I seem to remember (if I'm wrong please correct me) that the Magnus effect works regardless of the direction of the wind, whereas the sky sail needs the wind to be roughly in the same direction of travel.
They could be combined but as far as I understand these spinning columns are more generic
However, it can pull you forward when the wind is coming from the side. You change the direction of rotation based on which side the wind is coming from.
Without tacking, no (edit: solely) wind power systems will help when going straight upwind.
No, you are, unfortunately, incorrect.
> Without tacking, no wind power systems will help when going straight upwind.
In fact, the Magnus rotors will not provide any usefull thrust is both upwind and downwind scenarios.
If the wind is coming from behind won't it simply push the stationary cylinder, adding some thrust?
With a headwind or tailwind, tacking could be used but the increased distance traveled may offset the gains from the Magnus sail.
Our hypothetical container ship is roughly 400m x 59m, or 23600 m^2, and solar panels generate ~4.5 kWh/m^2 after inefficiencies, giving a total energy generated of 106.2 megawatt hours per day for a ship, if you had a big solar array above all the containers. Assuming an 85% efficient hydrogen fuel cell, that gives you losses both in storing and reclaiming electricity from that storage process. Assuming 1/3 of your energy can be used while generating it and the other 2/3 has to be stored as Hydrogen and then spent to power the energy, losing energy both ways, that leaves you an effective ~81 MWh/day.
Meanwhile the existing engines on that same container ship can currently run at about 90 MW, which means it can output more energy burning bunker fuel in one hour than our solar panels gave us in the entire day.
Container ship size: https://en.wikipedia.org/wiki/Container_ship#Size_categories
Energy per day: https://www.quora.com/How-much-solar-energy-is-generated-per...
Fuel cell efficiency: https://en.wikipedia.org/wiki/Fuel_cell
Container ship energy usage: https://newatlas.com/shipping-pollution/11526/
Obviously at this point fuel cells cannot produce the power output that diesel engines can at a given weight. But your power estimates on what a hydrogen fuel cell can do are off by a bit. Some quick searching finds portable 1MW fuel cells, existing 11MW power plants, and a planned 80MW power plant that's being constructed soon in South Korea. Obviously the latter probably weight too much for a ship today, but as the weight comes down that becomes a possibility.
My estimate didn't assume the ship left the shore with any hydrogen fuel. I (apparently incorrectly) assumed you meant that the ship would generate its own hydrogen during the day from excess solar while it was in transport.
If solar cells got effective enough to generate that much power, you’d probably be better off with solar + battery anyhow.
For a lot of these “why don’t they just” the answer is simply that they did the math and saw too small an upside for too big a risk.
They are trying this out to see if the overall concept works in practice or if it falls short.
That's one reason why Tesla was such a catalyst for the whole industry and EVs. As long as nobody else was really making too much of an effort, everybody could just drag their feet.
The rotors have to be powered. I believe the losses to friction and added mechanical complexity made it unfeasible in the past.
I'd love to see this succeed. The magnus effect is pretty counter-intuitive; it's always nice to see weird physics get used for real.
Here's a passenger's video about it. It spins quite fast: https://www.youtube.com/watch?v=Ir8YSRhMsXA
My understanding is that the main driver in the sail->steam transition was that steam ships were usually faster (and had much less variability in their schedule), and required smaller crews.
The glory of the "last windjammers" was largely enabled by very cheap labor from then-developing countries, allowing them to be competitive on a few select long distance routes.
As sled runners are to wheels, so the wing is to the Magnus effect rotor.
Lift goes up with the square of the radius. Think about that.
I'm in the process of ramping up a toy company that builds and sells kits for Magnus Effect drones.
I plan to just keep making them bigger, first for cargo then for mass transport. It will be necessary to move people efficiently by the million in the decades to come. Already floods and wildfire have begun to increase, soon enough the waters will rise and it will be needful to move our asses.
By using a simple recursive-fractal infrastructure there's pretty much no upper limit. Cf. "Tensarity" and Alexander G. Bell's cellular kites. Also Bucky Fuller's Cloud Nine. Self-powered.
I imagine huge aerial machines, more like gauzy flying buildings than aircraft, that carry a million or more people at a time. Cities in the sky.
 Tethered power generators, "Magenn" company, defunct? https://en.wikipedia.org/wiki/Airborne_wind_turbine
The CO2 emissions are easily estimated and not even close. A container ship can burn 225 tons of bunker fuel per day at normal cruising speed. At a generous 300 days in transit per year (they spend time in port loading / unloading / waiting), that's 67,500 tons of fuel per year. It's a massive number, but a drop in the bucket relative to the 913 million tons of oil consumed by Americans every year, the majority of which is spent on motor vehicle fuels.
Even assigning just 50% of US oil consumption to cars, you're comparing about 450 million tons consumed by American drivers versus about 1 million tons for 15 large cargo ships.
Jesus, I'm surprised we haven't seen all sorts of crazy ideas coming out of Maersk to reduce this overhead given that it's the bulk of their cost. Wind pillar things seem kinda tame compared to the shit I'd try to pull to save that level of money... Across all vessels no less!!
Quite a gap, and thats before you start factoring in batteries for the night, structure to support the array, storms...
Back of the envelope math says we're short by a factor of ~108. We can get savings in a few places:
(1) We don't have to match the full engine output with solar. Many container ships use super slow shipping at a fraction of the power,  says 10% engine load. With batteries you can still increase throughput substantially when needed.
(2) Panels can exceed current ship dimensions, perhaps greatly (tow a long tail of solar panels on floats?). Let's just go for double width and length for now.
(3) Efficiency gains. We're at 20% in back of envelope above but I can get that for my house. Let's say Maersk ponies up for 30% cells.
Still some ground to make up but at least we're in bullshitting distance of claiming it's viable.
> thats before you start factoring in batteries for the night, structure to support the array
Presumably there's some space/weight savings in not having an 80MW engine.
They really can't, though. Sure, there's plenty of space when the ship is out on the high seas, but any time the ship needs to go into port (kind of the point of a ship) or navigate tight waters such as straits or canals, then the footprint of the panels really has to not exceed the footprint of the ship.
Also it doesn't have to be solar directly, an electric propulsion system which can use hydrogen or high density battery/ storage which plugs into the grid eventually is good enough.
You don't need to drag the cells with the ship, they could be perhaps stationary middle of the ocean and charge the replacement batteries and you could line few such charging stations near the major shipping lines.
A few examples of electrical ships:
I'm guessing battery cost rather than weight is the main issue here. The Chinese ship is powered by the equivalent of about 24 teslas apparently for a whopping range of 50 miles. Compared to the overal weight of these ships, I could imagine extended range with more batteries would be feasible. I imagine the capital expense is the bottleneck here; not the weight. But it makes a lot of sense for shorter routes.
Having solar and wind to supplement energy might help extend their range by a meaningful percentage but probably not enough to make it worth bothering since you in any case have to recharge frequently; which is probably comparatively cheap (compared to buying fuel)
Wind powered sail drones already exist as well: https://www.saildrone.com/ These are tiny of course but they can be out there for months by themselves. You could imagine a scaled versions of these transporting cargo. With no fuel cost and no staffing cost, you can get economies of scale by simply having more of them rather than bigger ones.
The reason big ships are popular today is that they minimize staff and fuel cost. Big ships require a lot of power but they are overall more cost effective per ton of load than smaller ones. If you take people and fuel cost out of the equation, you can start thinking about different solutions.
Some interesting findings: The Panama Canal has an air draft of 201 ft imposed by the Bridge of the Americas; the Port of Oakland has an air draft of 220 ft imposed by the Golden Gate Bridge.
Height from waterline does not appear to be typically listed for ships, but I would guess that most cargo vessels do not have 100 ft of clearance to spare. I think this means these sails would only be fitted to vessels which generally don't care about height restrictions (e.g. ships larger than Panamax) or ships running predictable routes.
They may as well be propellers. It's great to improve the fuel efficiency of these vessels, but the word sail evokes a mental image profitably inconsistent with reality.
I mean 300 meters square of solar panel should be sufficient to push the ship at its nominal speed. For free!
On the plus side, if the insulation fails you could turn container ships into accidental fishing boats.
This is the statement I hear relating to all kinds of ocean-based renewable energy ideas. Sources are never provided.
The problem must have to do with economic viability and the replacement/maintenance costs exceeding savings.
Could you supply sources to elaborate on where the break even point of solar tail (or any two other ocean renewable energy) systems would be as relates to costs and benefits?
Edit: I don't really want to argue whether or not steel rusts in saltwater. My argument was that the break-even point of a "solar tail" is dismissed out of hand without sources because of land-based technologies being considered as the only ones.
We also do not need to provide sources for statements such as 'water is wet'.
Anything on a boat, or even shoreside near to the ocean is subject to corrosion and corrosion protection is a serious maintenance issue. I've lived 2 km from the sea and even there the nails would rust right out of the building due to the salt that the wind would carry in.
Edit: Come on. It's not impossible to engineer for ocean use.
Wave power generation:
Longer term: https://en.wikipedia.org/wiki/Submarine_power_cable
Even a simple scratch is enough to lay all your carefully produced work to waste.
But I asked for sources treating the proposal in the original comment, and got told that "water is wet".
Dunno why you’re expecting me to go all civil engineer on you, nor do I understand why you’re acting like I’m the barrier to the idea being tried.
Go do the math yourself, it’s your idea.
As there's a well known consensus that some factor (e.g. saltwater caused maintenance issues in this particular case) tends to be a game-breaker, then it's perfectly reasonable to dismiss 'without a citation' ideas that encounter this factor if the idea has no mention/citation of how they're going to fix, avoid or tolerate this.
If there's a plausible-seeming way that the idea can work despite the obstacle, then by all means we can discuss if that way will be sufficient or not; but if the idea simply ignores major problems, then there's nothing to discuss.
No one is arguing that it's impossible to build a bear with solar panels. The point is that you can't slap a cheap panel from Alibaba on a float and have any assurance that it will work reliably. Thus costs go up and the whole idea may become infeasible.
There are many good objections. It may be that the original comment does not illustrate the promise of this energy platform very thoroughly.
A 40-acre floating solar farm would add a LOT of drag. Better to make the solar farm stationary, use it to synthesize fuel, and run the ship with an internal combustion engine for power density. Maybe someday batteries could be used.
Can you provide sources that derive/explain/summarize the figures you present so that others may better understand the reasoning?
The rule-of-thumb max for solar irradiance is 1 kW/m^2 (noon, clear day, low latitude, etc):
The rule-of-thumb for the electric power output of a solar cell is about 20% of the irradiance.
And because this drops in the morning and evening and falls to zero at night, you realistically only get a bit more than 1kWh/day with a 1 m^2 solar cell.
And these ships require huge powerplants. Maersk's biggest ships use this engine:
which outputs over 80 MW.
No citation for the drag caused by a floating mat of solar cells. The fact that these enormous ships burn this much fuel should be evidence that dragging a much more enormous mat should show that dragging an even more enormous and more draggy mat would be a non-starter.
My acceptance of the idea that drag might be manageable has to do with volume displacement and not surface area.
A long shallow "tail" could exert orders of magnitude less drag (vis a vis surface area) than a deep heavy hull pushing up a big wake. (Related to why boats are long and narrow...)
Edit: The fact that you see that as a clear non-starter has me wading into Google results for hydrodynamics. It is definitely over my head, but I am curious. Is there a rule of thumb for drag in water that I'm not finding?
That's a lot. In contrast, the ship has an area of 24,000 m^2. A light-weight solar system might weigh 10 kg/m^2, so the whole thing weighs 20,000 tons. The ship has a staggering capacity of 200,000 tons.
So yes, it can carry it, but the 'long shallow tail' is really long - literally 20 miles, if it's the same 60m width as the ship - and really shallow. Maybe that's low drag, but if so, why wouldn't they build ships like that?
The application that no one will ever pay for might be a permanent, autonomous, very large, plastic garbage consuming vessel in the Pacific Gyre.
The form factor is less a limitation (in theory) than the will to allocate resources in such a way.
Using 20% efficiency panels gives us 0.2KW/m^2/hr.
According to this Quora answer  a small container ship uses 15,000kW: for one 24 hour day that means it needs 360,000KWH in energy.
If we assume 10 hours a day of full sunlight then we need 180,000m^2 (equivalent to 18 hectares or 44.48 acres or 33.7 football fields) of solar panels.
This of course overly optimistic as it assumes no drag nor increase in power needed to haul these solar panels (and batteries for use overnight, etc.).
Edit: Admittedly, you may be right, but without even back-of-the-envelope calculations, and with the assumption that these boats must go as fast as possible, I don't know why.
for comparison a Wärtsilä RTA96C is rated for over 80MW which means you'd need over 0.5million m^2 of PV panels to match this. (about 85 football pitches).
Feasible but expensive
What are the specifications of such a system that it would generate sufficient power
to cost-effectively augment or replace internal combustion, and what would the viable
price-point for installation be considering costs of bunker fuel?
Other comments [3, 4, 5] added the kind of information that might help to answer that.
I am interested in sources, and discussion which isn't immediately dismissive of something unproven.
Put another way, how much would low-grade petro-fuels have to cost before this became a viable alternative,
and what sources support your conclusions?
Edit 2: added a reference
The sail on that ship is 100' high, and looking at the aspect is around 15' wide, or 1500sqft. That type of sail I think only harneses half of that area, so half of 1500' or 750' best case.
I can say with complete confidence that if all the energy from two of my boats were towing one of those ships, even in a hurricane, it's going to increase fuel efficiency by approximately 0.0%
EDIT: I just did a random sample of wind speed  of points on the globe on international shipping routes  and it looks like they are generally around 10-15km/h. Thats barely enough to get my boat up to speed. There is a reason sailboats take very particular routes and don't just go from point A to B
> has installed 100-foot-tall rotating cylinders on one of its product tankers
And I thought IT loved acronyms.
Now who has the patent on SAILS!
This kind of reminds me of constant remakes of Spiderman ;0)
Also, if you look at pictures of windjammers, masts, rigging etc., would get in the way of cargo handling. Less so on a tanker compared to, say, a container ship, of course.
That seems less revolutionary than evolutionary.
> Maersk Line spent around $3.4 billion on fuel last year for its fleet of around 800 vessels.
Wouldn't savings from wind power be bad for the petroleum industry? And therefore by lobbyist extension bad for everyone?