Slashdot Mirror
Vermont City Almost Encased In a 1-Mile Dome
destinyland writes "A Vermont city once proposed a one-mile dome over its 7,000 residents. (They paid $4 million a year in heating bills, and HUD seriously considered funding their proposal.) The city's architectural concept included supporting the Dome with air pressure slightly above atmospheric pressure. (Buckminster Fuller warned their biggest challenge would be keeping it from floating away...) There would be no more heating bills, fly-fishing all year, and no more snow shoveling. And to this day, the former city planner insists that 'Economically it's a slam dunk.'"
But the answer comes from German city of Bremen, from a company dubbed Vector Foil. Vector Foil manufactures an innovative strong, lightweight, transparent polymer known as ethylene tetra fluoro ethylene (ETFE). At just one percent of glass, ETFE is described as 99 percent nothing. And considering that it can withstand winds of 180 miles per hour, it could be the breakthrough for the Houston Dome.
I'm not a mechanical engineer nor did any of my college coursework overlap with that but my gut feeling was pure skepticism and doubt. At least it's a long long way off if they follow through.
My work here is dung.
I'm not sure that going from heating a few thousand little boxes to heating one giant dome really qualifies as "no heating bills". Similarly, while shoveling snow off your driveway kind of sucks, it sure beats having snow build up on your habidome until the whole mess comes crashing down.
They'd better wait and read Stephen King's Under the Dome first...
And how much will it cost when ALL their water needs for lawns and parks and such need to be piped in? Not to mention that many plants need some of the water to fall on the leaves not just the roots.
What about insects and pollinators? Birds that fly south?
This is not very well thought out.
Didn't they try something like this in Springfield? (http://en.wikipedia.org/wiki/Simpsons_Movie
Come on now, this was already done in the Simpsons movie... Nothing new here!
No rain though, that's a plus if you live in the city and don't have a lawn. I'm sure you can have birds and insects inside the dome.
How do you kill that which has no life?
A couple of years ago Burlington, VT received 25.7 inches (0.65 m) of snow in 24 hours. I don't know what the density of snow is (I imagine it varies wildly), but that seems like a lot of weight.
OK, maybe the warm air can support that... but if that were the case, then on days when there wasn't 89 grillion kg of snow on top, there would be some pretty huge upward forces on the tent-pegs.
OK, well, then, there are vents, to let our some of the hot air. But then you waste all that energy heating air that you're venting.
But maybe it all works out somehow.
Never attribute to malice that which can be explained by mere idiocy.
You can get rain in large enclosed spaces. it's condesate. You might not want that raining on you. everything from evaporated dog urine, to aerosol diesel exahust, to flu viruses coming back down. Of course that happens now, but it's dillluted and also purified by the UV.
Now that said. I don't see why a dome has to have an impermeable ceiling. You could arrange things so that natural rain could be let in.
You could make the roof like a salmon ladder on a dam. there is some exchange with the outside air. just not wide open.
Some drink at the fountain of knowledge. Others just gargle.
Well, I had plans to do so, isn't that the same thing as almost doing it? No?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I think this is one of those things that look good on paper, but...
There are so many ways this could go wrong. It might be a way to breed viruses into an entire city, or keep carcinogens trapped for all to breathe. The Biosphere II was a fairly disastrous small scale experiment along these lines. Just imagine having an "oops" moment for a city of 5.7 million.
"Before God we are all equally wise - and equally foolish"
Albert Einstein
Alongside other problems (air exchange, summer disassembly, wind loads) Bucky's problem is real -- think hot air balloons.
Back of the envelope, if there's a 20'F difference on a 1 mi dia hemisphere, there's 16,000 lb lift per peripheral foot. That's not easy to anchor (10 x 10 ft foundation cross section.) And you definitely will need lots of steel or kevlar if you want the bottom wall be be under 1/4 inch.
Put a dome over the dome as a windbreak.
Given that I actually live about 5 miles from where the whole Winooski Dome was planned to go this is all pretty well trodden territory here in this part of Vermont. The real killer problems are twofold. One is just that nobody has ever done it before and who wants to be first? In theory its a great idea, but its always the problem you didn't consider that bites you in the end. The second and more practical problem was always snow load. As anyone that has lived in Vermont can tell you, we get plenty of snow. Now pile it up a few feet deep on top of that dome, it adds up real fast. Nobody was ever sure exactly what would happen with all that snow or how long it would stay up there, etc. Roofs regularly collapse around here from snow load. You REALLY don't want to have that happen to your dome. That brings up what was the real final issue. What happens if something goes wrong? Its not just like you wasted a bunch of money. Having that dome come down on top of a whole town? That would be a big mess indeed...
Basically if the concept is ever going anywhere someone needs to build one way out in the middle of nowhere and figure out the basic problems first. Winooski residents wisely decided that being guinea pigs maybe isn't such a great idea.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
You have a dome with a bunch of air in it, right? It has to be exchanged with fresh air, right? Now the city can tax the air their citizens people breath.
It is brilliant, really. They've finally found a way to tax the air we breathe!!
When town resident Ethyl Silane was asked her opinion of the dome, she inexplicably ran from her porch screaming "Eee-pah ee-pah eeepaahh!"
-One punk with a gun decides to piss on everybody's day.
-Even if you manage to deal with the weight of snow issue, how does everybody feel about living under artificial lighting for a couple of months each year?
-The expenses of building such a thing would be astronomical. Before even taking into account the dome itself, just building an air-tight wall around the city would pose ridiculously complex (and expensive) engineering challenges. Just managing water, waste and air control for an entire square mile contained environment would require exotic technologies, or billions of dollars worth of scaled up existing technologies. I've seen cities fly billions of dollars over budget trying to do relatively simple things like bury an ugly highway running through the city, or prepare to host the Olympic games. (Or *cough* build domed stadiums.) And then you've got your yearly maintenance costs. Parts wear out and you'd need a dedicated staff whose job it is to manage this thing. I wonder if that would be comparable to a heating bill?
-And in the Summer time. . . Well, guess what? That nice greenhouse effect (if you solved the snow cover problem) which kept you warm all Winter doesn't go away. How did the inventors plan on keeping all the residents from baking?
No doubt, it's a super-awesome idea and every single one of these problems could be cleverly solved and even turned to advantage with brilliant engineering. But it wouldn't be cheap, and frankly, unless the exterior environment was downright toxic or otherwise horrible, it doesn't seem like a particularly necessary idea. If all you're worried about is the cold, then that can be dealt with by spending a fraction of the same budget on the admittedly un-sexy idea of retrofitting buildings with improved insulation and more efficient heating solutions.
And don't forget. . . With the state of corruption in the country, if the energy companies felt that a source of revenue was threatened, domed cities would be, if not outlawed, killed with red tape and bought-off votes. You know it's true.
But I have to admit, the child sci-fi geek in me would certainly love to see at least one domed city of Utopian wonder constructed in my lifetime!
-FL
I'm not a mechanical engineer nor did any of my college coursework overlap with that but my gut feeling was pure skepticism and doubt. At least it's a long long way off if they follow through.
Thats what people thought about powered flight. Maybe you should leave this sort of thing to the engineers.
If they were planning to keep the inside air warmer than the outside air, then they'd find themselves covered by the top half of a hot-air balloon.
The outside air can change temperature very quickly. In winter it can shift by more than 20C between day and night here in Finland, and New England could be similar. Balancing the thermal buoyancy of the air with the mass of the dome would need some skill and unreasonably fast temperature controls to prevent lift-off or collapse. It's feasible for smaller domes, but at the kilometer scale it would be a real challenge. Buckminster Fuller was right - it would need good tethering to keep it down at times. The membrane tensions might also be quite large in places, with interesting dynamics, so that the mechanical design near tethers would also be interesting.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
In much of New England, "city" versus "town" is a matter of the type of colonial charter that was used to found the place. In New Hampshire and Vermont (I grew up on the border) which term is used is largely a matter of historical happenstance.
My Photography - http://ian-x.com
The Deathlings (comic) - http://thedeathlings.com
This would just lead to big arguments between the men and women of the town.
Absolutely not true. Here in Quebec, the roof of the Olympic Stadium is a similar deal, and huge hot-air guns are needed to try to melt the snow - and when it's not fast enough, it has to be removed mechanically, or the roof fails (and then they have to get out these huge mechanical "clothespins" to hold the edges together until it can be fixed.
Go by any ice rink in the summer and look at the pile of snow outside from the Zamboni ... snow just doesn't melt as fast as you think, even in 80 degree heat. Also, snow's a half-decent insulator (trapped air), so good luck melting a foot of snow.
In that same article:
"Another key use of ETFE is for the covering of electrical wiring used in high stress, low fume toxicity and high reliability situations. Aircraft wiring is a primary example."
So it's probably not that toxic if a film that thin starts to burn in (what is then) open air.
Manuals are your last resort only
Just cover all the streets with linear roofs