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Old 22-12-2007, 18:32   #16
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Putting a kite on a container ship would be real stupid Most of the mass needs to be below the water line, like on a sail boat.

Here are some examples of real uses!

KiteShip - Commercial Marine

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Old 22-12-2007, 19:28   #17
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Originally Posted by delmarrey View Post
Putting a kite on a container ship would be real stupid Most of the mass needs to be below the water line, like on a sail boat.

Here are some examples of real uses!

KiteShip - Commercial Marine

Actually, most of a ships mass, center of gravity is above it's waterline. It's the ships center of buoyancy, and how it moves under the CG as the ship rolls, that determines the ships stability

A ships stability is a compromise between two factors:
A too stiff of a ship means it has too much stability or too much of a metacentric height. Yes there is such a thing as too much stability. Too much stability creates too fast of a roll or what is called a snap roll. This kind of roll is too hard on people, it makes it more difficult to walk and it tends to get people sick. Basically it makes for a very miserable ride. The cargo is also much more prone to damage which is a major concern for break bulk and especially for container ships.

Too little stability and the worst could happen, a capsize. Cruise liners tend to have less stability (still within safe bounds) that provides for a slower and more comfortable roll. There is a formula that gives a rough measure of roll period (the time it takes the ship to roll from port to starboard and back). This formula gives an indication of the ships metacentric height, which equates to stability. The slower the roll period the lower the metacentric height and therefore the less stable is the vessel.

The point I am getting at, is that purely from a stability viewpoint, a kite could be done on a containership that had adequate stability but not necessarily on a tanker, breakbulk or a bulk ship if the stability is not adequate for doing such a thing.

Check this out: KiteShip - Commercial Marine

If I am looking at the computer generated picture correct, the kite is pointing forward of the starboard beam by perhaps 15 to 25 degrees? Does that look about right? This would mean the apparent wind on the ship is also forward of the beam..correct? This would mean the kite in this picture is actually slowing the ship down. It might be creating some insignificant lift on the ship but still if you imagine the vectors of the apparent wind... then one would be pointed aft.

Maybe somehow this kite is creating a forward force vector instead of an aft force vector... but I don"t see how.
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Old 22-12-2007, 19:31   #18
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The world's biggest motor-sailer? Someone should enter one in the Sydney-Hobart!
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Old 22-12-2007, 21:10   #19
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I don't see how it can make any money competing against modern day container ships, some of which are over 1000 feet long now These ships are on tight schedules and fully laden cruise typically at 23 to 27 knots. Does anyone see a problem yet?
From a cursory reading of the articles and the web site, it appears that they are counting on fuel costs rising substantially:
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When fuel costs become sufficiently high and/or governmental air and water quality regulations became sufficiently heinous, the commercial shipping industry will look to sail power as an assist to petroleum powered vessels.
You would have to work out what the fuel cost would have to be to make economic sense. If oil is free, nobody would use this device. If oil cost 1,000,000 dollars/euros per barrel, nobody would use it to power their ships and a sail becomes cost effective. Somewhere in between, there is a point where it is useful to use the wind-assist even though it means your ship is slower. The customers who just can't wait the extra couple weeks will just have to pay more. Of course, if oil prices get that high, we might also want to consider whether there will be any plastic trinkets to put in those ships...
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Old 23-12-2007, 09:39   #20
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Mark, right now gas & diesel are priced somewhat arbitrarily, at whatever prices OPEC and all think they can get away with without cuasing outright wars or killing consumption. The are (and over the years have repeatedly shown) outright masters at setting prices to get as much income as they can from whatever amount they put on the market.

The "real" cost of gas & diesel will inevitably ramp up to $5/gallon, at which point it can be made like other goods from other raw stocks. And the reason OPEC doesn't raise it much farther much faster now, is that IF they raised it to $5, someone else could build the plants to put synfuels on the market and tell them "Go pound sand, Your Highness."

So the only question is how long it will take to consume the dinoleum, and bring synfuels online--at which point the price will be $5/gallon. No question on that, just a little uncertainty on the exact time and price.

Meanwhile, the payback period on that kite is reasonably fast. We don't know how much lift versus pull (thrust?) that kite has, but it could reasonably take a fixed percent off fuel costs by "lifting" the ship, reducing wetted area and making it faster even without pulling it forward. All that good stuff, and the question of how it will affect overall motions and other real-life factors, is probably why they need to experiment on it. At some point, spending a half million on an experiment is cheaper, faster, and more reliable than spending the same half million trying to write a custom computer program to model the same effects--and not knowing if you've gotten them all anyway.

But the fuel costs? Heavens help us once (if?) China starts bidding in a big way.
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Old 23-12-2007, 13:12   #21
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<snip>
But the fuel costs? Heavens help us once (if?) China starts bidding in a big way.
Indeed. And I'm afraid it's not "if," but "when."

Here's an exerpt from The China Effect in The Daily Reckoning quoting some facts about China which appeared in a recent Mother Jones magazine:

~ ~ ~
"China is:

- The world’s largest consumer of coal, grain, fertilizer, cell phones, refrigerators, and televisions
• The leading importer of iron ore, steel, copper, tin, zinc, aluminum, and nickel
• The top producer of coal, steel, cement, and 10 kinds of metal
• The No. 1 importer of illegally logged wood
• The third-largest producer of cars after Japan and the United States; by 2015, it could be the world’s largest car producer. By 2020, there could be 130 million cars on its roads, compared to 33 million now. [emphasis added]

"More Facts:

• China produces half of the world’s cameras, 1/3 of its television sets, and 1/3 of all the planet’s garbage.
• There are towns in China that make 60% of the world’s button supply, 1/2 of all silk neckties, and 1/2 of all fireworks.
• China uses half of the world’s steel and concrete and will probably construct half of the world’s new buildings over the next decade.
• Some Chinese factories can fit as many as 200,000 workers.
• China used 2.5 billion tons of coal in 2006, more than the next three highest-consuming nations—Russia, India, and the United States—combined.
• It has more than 2,000 coal-fired power plants and puts a new one into operation every 4 to 7 days.
• Between 2003 and 2006, worldwide coal consumption increased as much as it did in the 23 years before that. China was responsible for 90% of the increase.
• China became the world’s top carbon dioxide emitter in 2006, overtaking the United States.
Russia is China’s largest timber supplier; half of all logging there is illegal. In Indonesia, another timber supplier to China, up to 80% of all logging takes place illegally.
• 90% of all wood products made in China are consumed in the country, including 45 billion pairs of wooden chopsticks each year.
• The value of China’s timber-product exports exceeds $17 billion. About 40 percent go to the United States.
• More than 3/4 of China’s forests have disappeared; 1/4 of the country’s land mass is now desert.
• Until recently, China was losing a Rhode Island-sized parcel of land to desertification each year.
• 80% of the Himalayan glaciers that feed Chinese rivers could melt by 2035.
• In 2005, China’s sulfur-dioxide emissions were nearly twice those of the United States.
• Acid rain caused by air pollution now affects 1/3 of China’s land.
• Each year, at least 400,000 Chinese die prematurely of air-pollution-linked respiratory illnesses or diseases.
• A quarter of a million people die because of motor-vehicle traffic each year—6 times as many as in the United States, even though Americans have 18 times as many cars.
• Of the world’s 20 most polluted cities, 16 are in China.
• Half of China’s population—600 to 700 million people—drinks water contaminated with human and animal waste. A billion tons of untreated sewage is dumped into the Yangtze each year.
• 4/5 of China’s rivers are too polluted to support fish.
• The Mi Yun reservoir, Beijing’s last remaining reliable source of drinking water, has dropped more than 50 feet since 1993.
• Overuse of groundwater has caused land subsidence that cost Shanghai alone $12.9 billion in economic losses.
• Dust storms used to occur once a year. Now, they happen at least 20 times a year.
• Chinese dust storms can cause haziness and boost particulate matter in the United States, all the way over to Maine.
• In 2001, a huge Chinese storm dumped 50,000 metric tons of dust on the United States. That’s 2.5 times as much as what U.S. sources produce in a typical day.
• Currently, up to 36 percent of man-made mercury emissions settling on America originated in Asia.
• Particulate matter from Asia accounts for nearly half of California’s annual pollution limit.
• Environmental damage reportedly costs China 10 percent of its GDP. Pollution-related death and disability heath care costs alone are estimated at up to 4 percent of GDP.
• In 2005, there were 50,000 pollution-related disputes and protests in China.
China's middle class is expected to jump from 100 million people today to 700 million people by 2020. [emphasis added]

"These statistics are drawn from The Last Empire: Can the world survive China's rush to emulate the American way of life? in Mother Jones magazine."

~ ~ ~

In an era where people all over the world are ascending to the middle class, it isn't only China that will be putting increasing pressure on all of the available resources, not just petroleum. And with peak oil having arrived, the time when crude could be easily, and cheaply, extracted is over.

As more and more people bid for resources that are increasingly more difficult, and expensive, to extract and bring to market, the price can only go one way. Shrinking supply+swelling demand=higher prices. Econ 101.

And as the purchasing power of the American dollar evaporates, that too will increase the nominal cost of fuel (and everything else) in $US. The day will surely come when an American will look back wistfully, and say, "I remember when a gallon of gas was only $5."

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Old 23-12-2007, 14:04   #22
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Of coure it is not that simple, TJ. There is every chance that some of the sprouting economies (India, China) will collapse in the coming decade, as problems of pollution, infrastructure, water shortages, and angry populations come into conflict. It's like an island full of deer or rabbits--with no predators and no stops, it booms, then busts.

And, the Chinese don't think like the West. They've pushed big into pebble bed reactors, so they an have a "cottage nuclear" grid built of local modules. They've got lots of dirty coal--and garbage. So at some point it will occur to them to duplicate (or steal) western technologies that can let them make their own synfuels, especially if their economics can work it better.

And if they keep churning out millions of counterfeit Disney DVDs, The Mouse may just nuke 'em before anyone else does. (Beware the Wrath of Mickey!)
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Old 23-12-2007, 23:11   #23
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From a cursory reading of the articles and the web site, it appears that they are counting on fuel costs rising substantially: You would have to work out what the fuel cost would have to be to make economic sense. If oil is free, nobody would use this device. If oil cost 1,000,000 dollars/euros per barrel, nobody would use it to power their ships and a sail becomes cost effective. Somewhere in between, there is a point where it is useful to use the wind-assist even though it means your ship is slower. The customers who just can't wait the extra couple weeks will just have to pay more. Of course, if oil prices get that high, we might also want to consider whether there will be any plastic trinkets to put in those ships...
LOL...excellent points Mark!
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Old 23-12-2007, 23:13   #24
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If oil is free, nobody would use this device. If oil cost 1,000,000 dollars/euros per barrel, nobody would use it to power their ships and a sail becomes cost effective.
When oil bcomes 1,000,000 per barrel ships will be nuclear. Proven powerplant for large ships. Relatively low risk.

We will always have to ship goods post carbon. Sail just ain't gonna be it.
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Old 23-12-2007, 23:19   #25
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I was just thinking the same thing Dan....you beat me to it. I don't think it would be an extraordinary expense or amount to a lot of training to get a reactor up and running on a merchant vessel. Especially now that container ships are approaching the same size as aircraft carriers..there would be some economies of scale here. There was a test reactor on a merchant ship called the Savannah years ago.

NS Savannah - Wikipedia, the free encyclopedia.

Compare this to the largest internal combustion engine ever made. This engine must have cost some serious money.

The Most Powerful Diesel Engine in the World Those are not dwarfs working on that engine.

It makes one wonder how much more expensive a reactor would be over this engine.
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Old 24-12-2007, 01:07   #26
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Nuclear may be a good alternative but I would think they may need to carry some serious fire power to defend it from the loons.

Mike
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Old 26-12-2007, 03:41   #27
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China is also the world's most populous country. In fact, one in every five people on the planet is a resident of China.
Chinese population + 1.3 billion ÷ World population 6.6 billion = 20%
(USA population = + 300 million = < 5%)
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