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Canadian Company Plans Solar-Powered Heavier-Than-Air Airships
savuporo writes "By crossing airships with airplanes, Solar Ship is planning to build a craft that can carry heavy loads long distances with a tiny carbon footprint. Filled with helium, they soak up rays from the sun to provide the energy for forward motion and fulfill its original design challenge – carry 1,000 kilograms (2,205 lbs) of payload 1,000 kilometers (621.4 miles). The craft is heavier than air, and uses a combination of helium filling its interior and its lifting body delta wing shape to stay airborne. Solar Ship shows plans for a range of different size craft for different duties."
It doesn't use up the helium though .. once it's filled it's full.
Second.. from Wikipedia "In 1996, the U.S. had proven helium reserves, in such gas well complexes, of about 147 billion standard cubic feet (4.2 billion SCM).[80] At rates of use at that time (72 million SCM per year in the U.S.; see pie chart below) this is enough helium for about 58 years of U.S. use, and less than this (perhaps 80% of the time) at world use rates, although factors in saving and processing impact effective reserve numbers. It is estimated that the resource base for yet-unproven helium in natural gas in the U.S. is 31–53 trillion SCM, about 1000 times the proven reserves."
Even if they are wrong by a factor of ten that still gives us a few centuries of helium left .. by which time hopefully we'd be either creating helium via nuclear fusion power plants or able to bring back abundant quantities from Jupiter.
Oh the humanity...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Shoot. Prior art from the 1600s. http://en.wikipedia.org/wiki/Vacuum_airship
Short answer: no.
Longer answer:
It's very difficult to achieve a vacuum in the first place. If there is even the slightest leak the air will be rushing in with the force of a one atmosphere pressure difference. With a lighter than air gas the pressure difference is quite low and any leak can be handled with a periodic "topping off" to keep out the air. Even if we had the technology to produce a "vacuum ship" it would not likely be cost effective since the lift gained by a pure vacuum is very small compared to that of helium or hydrogen gas.
An envelope that held a vacuum for lift would be under considerable forces. There is the force of holding back the outside air. There is the force of the gondola which carries the cargo. There would be wind, birds, stupid rednecks shooting at it, among other things that would try to punch holes in it or rip it up. It's just not practical.
I am armed because I am free. I am free because I am armed.
I would love to know this. My physics isn't great, but I did a quick Google.
It looks like the consensus is that it is not possible, those materials do not exist.
The other thing is that is would not make much difference than using helium:
Density of air is 1.2 kg/m3.
The density of helium is 0.166 kg/m3.
If we had a balloon filled with air, and replaced it with helium, the density reduces to 14%. This means that that much helium could support 86% of the weight of the air. A vacuum's density is 0, so it was possible it would support the weight of 100% of the air it 'displaced'. So a perfect vacuum is only 16% better at lifting (in air) than helium is.
In fact helium, once lost to the atmosphere, is irrecoverable in any useful quantity. The only way we can get more is to filter it out of natural gas trapped underground. Helium could therefore be considered a petroleum byproduct.
But since it is a lot hotter in that direction, all those missions to the sun would have to be done at night.
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The interesting thing is that, if they are mylar (or 'foil') balloons, you could do just that. It is the latex, and most plastics like polythene, that leak helium.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
http://www.johnmcphee.com/deltoid.htm
Why is Snark Required?
Helium is the least reactive noble gas, and much lighter than air. Common sense says that it will rapidly leave our atmosphere. I dont remember the exact details (I had this brought up in a class once), but it was some combination of the ascending helium reaching escape velocity and solar wind peeling off anything that might try to settle in a super high orbit. The impending heium shortage is a well known problem, and a significant part of the reason I get an overwhelming urge to punch clowns in the face every time I see them handing out balloons.
And frankly, almost every alternative energy solution has serious if not fundamental flaws. If they didn't, we would already have been using them. Seriously, this "you're all just pessimists who work for oil companies and kick puppies" crap is getting old. Going off half cocked with some doe-eyed fantasy of a technotopian future filled with helium blimps and solar farms the size of small nations isn't going to fix anything. It took a hundred years and a lot of ignorance to get stuck in this energy policy quagmire, and logic dictates it will take twice that amount of time to get back out. You dont extract yourself from quicksand by thrashing about in a panic.
http://www.hybridairvehicles.com/
The US military is buying half a billion dollars worth of kit from them... Or rather through Northrop Grumman.
http://www.flightglobal.com/news/articles/video-northrop-grumman-wins-race-to-revive-hybrid-airships-with-517-million-order-343259/
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But the same problems would face the designers of a large airship. The helium may not leak through the skin itself, but it will be challenging to keep all the seams tight enough to prevent leakage. Also, after a while, microscopic cracks could develop due to flexing and bending in the wind.
...although one already explored by SF authors such as Norman Spinrad in Songs from the Stars. 1000 kg weighs 2200 pounds and is basically the load of a pickup truck. By far the easiest way and cheapest way to get a load 1000 km is to build a solar powered electric railroad, especially if you don't care how fast it gets there at first. Of course, with solar collectors on the ground, there is basically no practical limit to the power you can deliver per kilogram and consequently one can get the load to destination at very high speeds with a new design.
The difficulties with a solar powered helium dirigible are manifold and have already been pointed out -- finite supply of helium, helium needed for kids' balloons and (eventually, perhaps) as thermonuclear fuel (at which time we'll kick ourselves for wasting it for decades in kids' balloons), absolutely impossible to keep sun-warmed helium inside any sort of bag. Weather and wind make the transportation dangerous or impossible (given the wimpy peak power likely to be available to move the bag -- probably inadequate to overcome even a very modest headwind). The danger of 1000 kg loads being dropped on people's heads if weather conditions exceed the limited capacity of robot brains to solve weather problems and the lifter breaks up, pops, catastrophically fails.
It isn't quite inconceivable that one could build a solar-solar system -- a solar balloon for lift, solar power for "thrust" -- although again I think that the force of wind pressure instantly will exceed the peak thrust of any onboard solar system on even a very sunny, nearly still day. To lift a metric ton you'll need a rather large balloon, so very small overpressure on the upwind side will exert a huge force downwind. And you'll still have the problems with weather, with the fact that the sun doesn't shine at night and you can't carry batteries or the whole design becomes laughably impossible, not marginally feasible (either one, Helium or hot air).
But rail? Piece of cake. Hell, you could probably deliver a steady stream of pickup truck sized loads driven by solar collectors along the roadway -- 70-100 watts per square meter of collector, plenty of room for 1000 watts per meter of actual track along the 1000 km route. In fact, the track (with a mere 12 meter wide roadway, 2 meters of which is track and vehicle) will generate anywhere from 100s of megawatts to a gigawatt of power on any reasonably sunny day. Assuming 10 kW per metric ton to move payload at 100 km/hour or better, one can move anywhere from a minimum of 10,000 metric tons up to a maximum of 100,000 metric tons per 10 hours of useable daylight day, for the amortized capital cost of the solar powered roadway. (Don't whack the math too much, these are all estimates and YMMV). The cost of the solar electrification is currently a bit over $1/watt, installation and collection will double that. Call it a $5 billion project (the cost of a couple of weeks in Iraq), build it on an existing rail corridor between (say) Detroit and Chicago square in the heart of the industrial heartland. If one charges $10/ton for transport (pretty cheap, one would think) it grosses close to $1 million/day running the rail at capacity, $300 million a year, payback of the initial investment in 15-20 years.
As is so frequently the case in solar projects, this is maddeningly close but not quite a cigar. For a billion dollar investment it would be a no brainer -- payback in 3 years (more likely 5 with operating costs), pure profit thereafter. For 2 or 3 billion dollars it is attractive -- an effective yield of maybe 5-10% on investment in the long run. For 5 it is right down there at 1-3% yield, implying a fairly long period to wait for a not-too-large ROI, plenty of risk. Drop the cost of solar cells by one more factor of two and it will happen all by itself. Drop it by a factor of four or more, which is entirely plausible given sufficient volume in the market (and this project alone would consume
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
Actually the helium shortage is strictly a manufactured shortage, created by the US Government when they (principally the Navy) decided blimps were not its platform of choice. The Government decided to dump its huge reserve of helium at submarket prices, and as such nobody bothers to extract helium from all the natural sources where is has historically been obtained.
Government passed a law shutting down the helium reserve. The law stipulates that the US National Helium Reserve, which is kept in a disused underground gas field near Amarillo, Texas – by far the biggest store of helium in the world – must all be sold off by 2015, irrespective of the market price.
There could still be as much helium produced today as ever, were it not for cheap government surplus sales, as it is, nobody bothers to extract it.
See article here:
http://www.independent.co.uk/news/science/why-the-world-is-running-out-of-helium-2059357.html
Sig Battery depleted. Reverting to safe mode.
So what's lighter than helium and hydrogen? Vacuum! We need more advancements in vacuum balloon technology.