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Computer-Controlled Cargo Sailing Vessels Go Slow, Frugal
An anonymous reader writes "Big container ships are taking it very slow these days, cruising at 10 knots instead of their usual 26 knots, to save fuel. This is actually slower than sailing freighters traveled a hundred years ago. The 1902 German Preussen, the largest sailing ship ever built, traveled between Hamburg (Germany) and Iquique (Chile): the best average speed over a one way trip was 13.7 knots. Sailing boats need a large and costly crew, but they can also be controlled by computers. Automated sail handling was introduced already one century ago. In 2006 it was taken to the extreme by the Maltese Falcon, which can be operated by one man at the touch of a button. We have computer-controlled windmills, why not computer-controlled sailing cargo vessels?"
The bean-counters decided it was better to operate off a relatively fixed cost like fuel and have a dependable schedule. The whole story of the 20th century has been "Yeah, you could do this or that but it's just simpler and cheaper to use fossil fuels." Environmentalism won't drive alternative fuels, economics will. If it becomes cheaper to use sail, we'll go back to sail. The cost of fuel will only rise from this point, peak oil is here, so the economics we need for sail should be here now.
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Why have a crew at all? Think of the surprise that the Somali pirates would get if they got on board and found no one. Just a sailboat with a locked server room.
I'm sure the pirates would love to see computer controlled, slow moving ships. Unless you have robots/zombies guarding them? Or sharks with frickin lasers on their heads?
INAM (I'm Not A Miller) and I'm not up-to-date with the tech, but as far as I'm aware windmills can't plough into harbours destroying themselves and their cargo, potentially killing lots of people at the same time.
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There's already some good ideas about putting sails on container ships (that don't get in the way of loading, like masts would do)
See slashdot from 2007:
http://hardware.slashdot.org/article.pl?sid=07/11/26/1925210
Yeah... Let's send robot ships out there to travel to a port and then wonder WTF happened when it doesn't arrive... Did the scurvy pirates get it or did it drift off course or did it sink?
If only they could invent some type of Global Positioning System. I can see it now... you would need a couple dozen or so satellites to ensure coverage over the planet. They would broadcast some type of signal. Then all you would need is some type of devices to read the signal from two or three of these satellites to get a 2D or 3D positioning.
*runs off to patent office*
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SkySail: using the a computer controlled parasail to improve fuel efficiency. Article http://www.popularmechanics.com/outdoors/boating/4235055.html
Speed from Sail power is proportional to drag, not weight.
can it be a big mother mounted windmill and an electric motor???
bonus being- no tacking into the wind-- rotate the damn windmill and head on into it...
every day http://en.wikipedia.org/wiki/Special:Random
It reduces drag relative to cargo and increases stability in bad weather which protects the cargo.
I don't expect sail power would scale to the size of modern container ships.
Sure, a sail array may not be the best solution for getting a container ship underway from a standstill, but once the ship reaches open ocean, and a course is set, sails can be used to replace some of the engines' thrust, saving fuel.
Considering that container ships consume 100-400 metric tons of fuel per day, even a 5-10% savings would be pretty damn significant.
(Of course, 100-400 is a very broad range - the 4,250-TEU Arafura consumes ~65 MT / day, while the 11,000-TEU Emma Maersk chows down on 350 MT per day, so yeah, YMMV).
Marine Diesel is about $ 420-450 per metric ton right now.
As an intellectual exercise, let's take a 6,000-TEU ship consuming 100 MT/day, making the Shanghai-Long Beach run at express speed (15 days), and let's take the cost of MDO at $ 435.00 per metric ton.
At 5% savings, the sail array will save $ 2,175 / day. Multiply by 15 days = $ 32,625 saved per trip.
To put this into even more of a perspective, the average lifetime of a container ship is 27 years. Assume it's running 75% of the year. (27*365)-25% = 7,391 days. Take $ 2,125 saved per day * 7,391 days = $ 15,705,875 saved.
Is $ 15.7 million enough to pay for the sail array + computers? Seems like it to me.
Hmm, looks like 5-10% was a very pessimistic estimate. If this article is correct (thanks, Aceticon!), up to 35% could be saved. You do the math.
This may not count as zero impact in the short term, but ...
As kids we visited the atomic museum (I forget the name) in Los Alamos, NM. The had some sort of simulator where you could turn dials corresponding to different human activities. The output was a list of various things such as pollution, hunger, population, and so on. AT least a dozen. All of them had a red, yellow, or green lights. A few had numerical output.
So we started turning this knob, then that. Lights would go back and forth between red, yellow, and green. Suddenly the whole board lit up green. Except population, which was red and said 0. I guess we solved most of the worlds problems.
So I'm reluctant to say there's nothing we can do with zero impact. But I'm even more reluctant to try the one idea that might work!
The world is made by those who show up for the job.
Cargo ship speeds go up and down with the costs of ship charter and fuel, and with the demands of customers. Read "The Box", a history of shipping containers and the ships that move them.
Right now, the Baltic Dry Index is down to where it was around 2000, after a huge 5x spike last year. So there's a huge glut of available container ship capacity, charters are cheap, and freight rates are way down. So operators have to optimize for low cost at the expense of speed and throughput.
There's also no big demand for speed from the customers. Much of what's being shipped is going into storage anyway. Unsold cars are piling up near ports, filling up storage and spilling over into rented parking lots. That's presumably happening with containerized commodities too, in cases where the buyer can't just cancel the order.
It's one of those things that happens in a depression.
You can not move forward by capturing energy being used to push you backwards. To move forward would require more than 100% of the energy that you're capturing. It doesn't work.
Those numbers only work when your personal interest rate is 0, which is rarely the case.
Realistically, you need to adjust for the time value of money. ($100 now is worth more than $100 27 years from now, as I could make interest off of it)
So, if we assume that the savings are every month, with a 3% interest rate compounded monthly, we'd have (12x27) payments of about $49,617 each with 0.25% interest per period:
PV(A) = (49_617 / 0.0025) * ( 1 - (1 / 1.0025**(12*27) ) )
Which works out to just over $11 million. The install cost would have to be less than this, to deal with the reoccurring costs of maintenance of the new system.
Oh ... and if the interest rate were 6%? That $11mil estimate would be cut to under $8mil, or about 1/2 of your estimate. In a good market where we might be able to make 18% return, over 27 years, it's worth less than $3.3M.
Now, I don't know how much container ships cost, but if I can add another ship and move more containers, that may give me a better benefit for the same cost.
(and, I know you later said that the actual savings were higher -- but the point is, you should _never_ just multiply reoccurring costs or savings by the number of periods to get the equivalent present value, especially for periods of years.)
Build it, and they will come^Hplain.
Some moron did the article. A moron who has never been to sea, obviously.
I challenge any weekend warrior to find me any cargo ships that make 26 knots, anywhere, today, last year, or last decade. In an emergency, a FEW of them might make that kind of speed, but they can't sustain it day after day, like naval ships can. A blown boiler is sure to ruin anyone's day.
Warships didn't even make a habit of running that fast, 30 years ago, when fuel was cheap. The first time I crossed the Atlantic, I asked "How long?" like any kid in the back seat of a car, on a long trip.
The answer: "We can be in Portugal in 5 days, if we burn x gallons per minute, or we can be there in 11 days, if we burn y gallons per minute. So, we'll be there in 11 days."
The destroyer I served on was capable of doing about 35 knots (officialy 30+) and we could catch ANY commercial freighter, tanker, container ship, or whatever.
IF, and I say IF, cargo ships were capable of 26 knots as the article says, THEN, they would be transiting the hi danger piracy zones at that speed, and the pirates wouldn't be catching them.
Many 19th century sailing ships could routinely take most commercial traffic in a race, even BEFORE companies started slowing down to conserve fuel. Revisit the sailing times for ships such as the Cutty Sark, then look at the sailing times for today's tankers and container ships. Real sailing times, not "best case scenario with favorable winds" sailing times. ;)
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Actually, in the long run it'd be a very good thing if a band of Somali pirates got their hands on some nuke fuel.
The pirates themselves don't have the capability to convert it into anything more than a dirty bomb.
The pirates could sell the material to the terrorist organization du jour. They might be able to make a slightly more effective dirty bomb out of it.
That's if the focused attention from the bulk of the western world hasn't given Somalia a new coastline that is twenty miles further inland than the old one.
Somalia is an honest-to-diety failed state. The U.N.'s negligence in this matter is criminal. Iraq and Afghanistan, while not friendly with us were at least stable. (So we go in and destabilize them...) Meanwhile a country that should have intense international attention is ignored. Sadly, it's going to take a few Americans getting offed to trigger the good ol' Pearl Harbor reaction. It's going to suck for those few Americans but those Somali pirates are in need of a history lesson on what the phrase "to the shores of Tripoli" is referring to and that no country does knee-jerk reactions like we do (and when we do it the whole world feels it).
You capture much more energy than is pushing your windmill blades backward; most of the energy you capture is spinning your blades around in a circle.
You can certainly move forward using the energy that is pushing your working surface sideways. A sailboat on a tack moves upwind, because the sail is pushed downwind (which is counterproductive), but it is pushed even harder sideways across the wind. Windmill blades move sideways across the wind at all times; think of the blades as seperate sails, on an eternal upwind tack.
Designing a windmill-driving-a-turbine contraption to make headway upwind poses no impossible hurdle. Whether enough efficiency can be obtained in practice is a different matter. Carts with windmill powered wheels that move directly upwind have been constructed by countless physics students, including me.
We're not talking about unmanned ships, just ships with sails which are adjusted by machines instead of dozens of sailors.
is. The captain turns the steering wheel and a bunch of motors do the furling/unfurling.
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Actually the pirates are doing the real work of nation building just as pirates usually are. It just happens that they are on the other side and not ours otherwise we would call them the navy or entrepaneurs.
Another criminal activity in Somalia is the use of their waters/ports/military supply routes by rich trading nations who pay nothing back for what they are using and only get away with it because Somalia is a failed state. However, now that they are getting more organised (less failed) we call them pirates because we (USA) isn't in favour of stability, democracy or anything like that unless it profits us.
http://www.republic-news.org/archive/208-repub/208_potvin_pirates.html
Stupidity is its own reward.
Sails, whether made of traditional textile material or something more newfangled will probably not power those container ships moving all that crap from far-east to west. Wingsails on the other hand could be used for generating a sizeable portion of the needed thrust. They also have the advantage of being much easier to automate, give more thrust per surface unit and give better handling. Rigid wingsails can be covered with photovoltaics giving even more 'free' power in the right circumstances.
Point your favourite search engine to 'wingsails' for more info on this subject...
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