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Start with a skyscraper that is wide at the bottom and tapers slowly to a point at the top. Make sure it's located near plenty of cheap water. Add a fountain at the top, and have the water trickle down all of the sides.
This should provide significant cooling, and have the additional advantage of
looking like a giant shimmering fountain sculpture.
Boiling fountain skyscraper sculpture
[bungston]'s idea that inspired this one. [Worldgineer, Jun 21 2005]
(?) Roof Sprinklers
http://www.pnl.gov/...tecap/whitecap.html
For [bacon] [Worldgineer, Jun 27 2005]
(?) Swamp cooler
http://www.sahra.ar...ons/home/cooler.htm
Another way to use water evaporation to cool things. [bungston, Jun 27 2005]
The Shard, London
http://www.google.c...AQ&biw=1280&bih=905
Perhaps the ambient conditions wouldn't suit Worldgineer's calcs! [gnomethang, Jun 30 2011]
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Aside from the easy access to water, I suppose the pyramids would be a good subject. |
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soak all the smokers hanging around at the bottom. |
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Wonder what it would cost to operate the pump. |
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You'd be saving on air conditioning energy (chiller energy, pump energy, fan energy), so this may even cost less. |
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Could you use some kind of slow-acting solar heat pump? I don't even know what that would entail... |
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I guess you could build it on a natural spring, though then it would come out hot. |
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Hmm... I'm forseeing unpleasant algae growth on the sides. |
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Yes, I'd think you would still have to wash the windows to avoid growing things. The water's already there though, so it should be easier (yet more soggy). |
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Cool. I wonder how to get the water to cover the entire surface, starting as it is from the narrowest point, and having to spread out as it goes. (If that is your intent. I mean, I think that all the windows should get wet, for the hell of it, at least some of the time. I guess directional nozzles at the top would probably help, but having looked up at the pyramid replica in Las Vegas, that's a huge expanse of glass to cover, and to have any decent flow all the way accross the bottom, you will need some huge amount of water at the top.) |
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I was thinking of basically having a small gutter between each floor, perforated at each of the windows. You'd need to level it precisely, or you can control the level with actuators to only rain on the sides with sun. |
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As the pump doesn't rely on the velocity of the water falling could turbines be fitted? These could power suckered simple robots which drift around the surface wiping it clean of algae, etc. |
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Yeah, I like the gutter idea. I might build a scale model of it, just for fun. I like to mess around with flowing water, and need an excuse to start makng sculpture again without the intention of actully making art. Thanks. |
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Douglas Adams wrote (said in an interview): |
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"I get very worried about this idea of art. Having been an English literary graduate, I've been trying to avoid the idea of doing art ever since. I think the idea of art kills creativity." |
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My thoughts exactly, once he went and thought them, and generously allowed me to share them. |
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Sorry for the interruption. I get little outlet for grown-up thought with my 2 small kids and overworked (by her standards) wife. |
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Good quote, and concept. If you're worried about doing art "right", you'll never get any made. Please keep me updated if you do build this. |
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I was thinking more about power requirements and evaporation. If it turns out that too much water evaporates by the time it flows to the ground, more water can be added at lower levels. This would also reduce the amount of pumping needed. |
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//everyone inside would assume it is raining outside, and would not be distracted by the desire to go out doors// |
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But I like it when it rains. |
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The entire building would be copper clad. This would prevent algae. I assume there would be some water recirculation, as with most fountains. On still days, you could add vinegar to the water and restore the gleaming copper finish. |
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On windy days, I think everyone downwind would be soaked. Not the building for Chicago. Also because the falling icicles would perforate passing cars. |
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Potentially lethal Legionella infections could ensue!. You could, of course, mitigate this.
Any idea as to the size of the pump/volume of water required (as per [bris]'s anno?. also an estimate of the cooling effect?. |
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Assuming a 100 story building, 15 feet per story, and an average of 30,000 square feet per floor, that's about a million square feet of surface area. I'd rather not calculate how fast the water falls - can we assume a foot per second? Assuming 1/8" of water thickness 2/3rds down the building on a moist day when no water is lost, that's 7.2 cubic feet of water a second, or 3232 gpm. |
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The water covering the building should remain very near the wet bulb temperature. Assuming an outdoor drybulb temperature of 90F*, a wetbulb of 75F*, and an internal temperature of 75F, an 80% glass building using double pane glass with a U value of 0.3 would save about 3.6 million BTU's per hour, which corresponds to 300 tons of cooling. |
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Every pound of water evaporated will remove about 970 BTU's of heat, so that's about 3711 pounds of water per hour evaporated. This means the building will lose water at a rate of about 6.2 gpm under these conditions. |
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* Making sure this is reasonable, I checked Houston, TX's weather today - drybulb = 94F, wetbulb = 68F. These assumptions are certainly reasonable. |
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Cool!. That certainly seems to help. You must offset the cost of the installation against the cost of running the equivalent CHW but it looks good. Don't forget the bypass for the CEO's penthouse! |
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If this were built in a warm climate (Riyadh?), you could also leave out the glass windows, substituting the smoothly falling sheet of water covering the building exterior. |
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Not much cheap water there, but the Saudis don't seem to need things to be cheap. I suppose a similar system using oil may not be ideal. |
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I think in a sufficiently warm and wind-free area a building with no exterior walls covered with waterfalls would be a beautiful design. |
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Just on a side note://The entire building
would be copper clad.// ... and water-
covered? What happens when lighting
strikes? |
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/What happens when lighting strikes?/ - You get some very impressive contrasty shadow effects. |
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This is such a cool idea. I am having visions of water streaming down the side of the TransAmerica pyramid in San Fransisco. Something would have to be done to keep the water from blowing around too much. I haven't looked into this but what about making the building material a polar substance so the water will be more adhesive or would that not help very much? and as for washing the windows, how about bungee-jumping with squeegies?
Regardless, its still a cool idea |
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I just realized my previous calculation ignored solar radiation absorbed in the glazing and walls, which is quite significant. I don't feel like running the calculation, but the extra cooling provided will be large. |
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[gads] That's actually a little bit expensive. Assuming about .7 kW/ton (.6 is fair for a large chiller, then a bit for heat rejection, etc.), traditional cooling would only need 210kW for that load. Of course, factoring in the extra solar load mentioned above, this number will go up while pumping will stay the same. |
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The cheapest water is saltwater. From the evaporation, you'd grow nice looking salt crystals all over the windows too. Maybe looking like snowflakes. |
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But using so much water, and adding soap or chlorine to it, is just an environmental nightmare that sours this for me. Maybe if we could just live with the algae & salt crystals? |
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Transamerica pyramid - yes! |
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[soph], water's the ultimate renewable resource and is far more environmentally friendly as a cooling solution than using fossil fuels to run power plants to supply electricity for a chiller. Chemicals could be recycled (chlorine may evaporate, but there are alternatives), or you could just use person-power (well, people with squeegies) to keep the windows clean. |
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Sorry to burst your bubble guys but this is totally not feasible. Using worldgineer's example, the building would be losing water due to evaporation at the rate of say .9 kg/square metre per second (REALLY hard to estimate but this is a conservative number) and converting the 1 mil square feet to metres you get 274,320 square metres you'll be losing water at a rate of 246,888 kg per second on the whole building. converting that to gallons thats around 65,000 gallons per second. In other words the pump would have to be pumping water at a rate of over 65,000 gallons per second for the water to reach the bottom of the building without evaporating. That's an INSANE amount of water. Also remember that this doesnt take into account the wind that there will most definately be at the top of the building which helps evaporation and also blows away some water.
Making the assumption that you will be having a moist day every day is quite unreasonable. |
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I recommend taking the time to look at your numbers and asking yourself if they are reasonable before reporting them, as a general practice. Your numbers indicate the water will provide about 188 million tons of cooling, likely enough to cool a major piece of Texas. Your estimation of a kg per meter per <i>second</i> seems, well, not very conservative. Think of a 1 square meter puddle containing 10 kg of water. Will it dry up in ten seconds? |
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As for modeling a moist day, I stated my calculations used 90F db and 75F wb, which is certainly not moist. I do need to add calculations for direct solar radiation, and will. |
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I found a number for horizontal solar radiation: 2080 BTU/sf/day (max, Washington DC). Walls of even a sloped building won't get all of this radiation, so I will use 50% of this for the side seeing the sun (a conservative estimate). Since only about one side sees the sun at a time, we multiply this by a quarter (ok, I'll use 30% to again be conservative). Choosing blue glass for this building, we get a solar absorptance of 0.24. Multiply these numbers by a million square feet, and we get 75 million BTUs, which is another 6,240 tons of cooling and 77,200 pounds of water per hour, or about 130 gpm. |
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For a building this size you'd expect about 1200 tons of cooling, so it appears my assumptions were too conservative. |
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A side note for the alleged algea problem. Algea grow in still or almost still water. You could make the trickle a little faster (a flow perhaps) and algea won't be able to stick. |
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Adding salt would kill the algea [sophocles] but would leave [worldgineer] with a salt residu (on the upside it would increase the amount of sweet water on the planet and you could make money selling the salt). |
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[ Trickytracks] Nothing. Cage of Faraday effect. Stay clear of the frame and you're okay. |
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[cypcom]. //..274,320 square metres you'll be losing water at a rate of 246,888 kg per second..//
You multiplied the square meters with 0.9. As I read this idea, the water is a film that trickles down over the windows. Therefore you cannot translate square meters to square gallons. You'll have to translate the amount of water per square mile (I'll leave the calculation to the smarter guys).
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OK. This is sounding better now. The ecological toll is really nothing compared to the other methods anyway. |
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Water is renewable, yes. It's not consumed chemically as often as just moving around in time/space & phases. |
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But good, clean, freshwater that's essential for life is much more rare, and entropy's not on our side. (Poison is not easily reversable.) So, the salt-water solution looks to be best. |
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Usually I don't like to overanalyze HB ideas, but Worldgineer's ideas are usually great playgrounds for seriousness. |
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"Worldgineer's ideas are usually great playgrounds for seriousness." Well said, Sophocles! |
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There's a somewhat popular belief in Missouri that one of those perforated trickler hoses along the ridgeline of your roof can reduce air-conditioning costs more than enough to pay for the water used. I've never seen it even attempted, let alone costed. |
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/ perforated trickler hoses along the ridgeline of your roof / - What an awesome high school science project this would be! |
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You could either do the experiment with cooling the whole house and average electrical (air conditioning) use + water use on hose days vs nohose days. Alternatively you could do the experiment with side-by-side sheds, one with hose and one without. You could follow air temperature inside the sheds. |
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It occurs to me that this would be a simple solar cooler - the solar panel would operate an electric aquarium pump. The pump would send water to the top of the shed, and on coming down it would go back to the reservoir for reuse. The panel would not need to be on the grid, which would make it substantially cheaper (much of the cost, in California at least, is safety crap involved in hooking the panel to the electrical grid). Water which did not evaporate would be reclaimed - probably hotter, but that is OK. |
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Rooftop sprinklers are a known energy saver in hot dry areas with (comparatively) inexpensive water (see link). The water is generally recycled, so if you are just using a soaker hose and letting it run down the drain it may cost more. I can imagine it working using sprinklers and water control set to pulse on every minute or so, with the duration determined by temperature to make sure you aren't wasting water. Nothing the average homeowner could do themselves, but I can imagine a fairly inexpensive device an entrepreneur can have built to start a roof sprinkler instillation business. |
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Thanks, I'd forgotten about those guys. |
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Can we put bubble soap in the skyscraper water, just to see what it looks like all foamy? We could pretend it was reflecting sunlight or insulating something. |
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Yes, and dye it pink for Valentine's Day. |
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Has anyone considered the effect of the heat leaving the building through the water on the water itself? Water has a relatively high heat capacity but it also takes a while to let it heat up. If the building is really tall the water at the bottom might be too warm from the floors above to effectively cool the bottom floors and if it is too short then the water would still have some cooling ability not used. If it is a recycling pump then there might not be enough time for the water to discharge its heat energy before going to the top again. This isn't an attck on the idea but just some food for thought. I still think it could be quite a feasible endeavor. |
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And what the heck kinda fun would be in a "playground of seriousness?" Thats like a "circus of banking" Almost oxy-moronic. |
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I don't know, I'd probably go to a bank circus just to see a bunch of clowns in business suits try to fit into an economy car. |
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Liquids, including water, are nicely self-balancing. Add heat and they evaporate faster, cooling themselves down. I expect the water to quickly reach and stay at the wetbulb temperature. |
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//And what the heck kinda fun would be in a "playground of seriousness?"// |
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Just about exactly like the amount in the halfbakery, seems to me. |
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[Acrimonious Obfuscator], Convection currents inside the building could allow even cooling for all floors.If the air inside the building is cooled more at the top floors than the bottom floors, then the cool air will drop down through the building if the internal airflows are designed correctly (as hot air rises, so cool air will fall). Hot air from the lower floors will rise, to be cooled. |
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There is a building in NYC with waterfalls running down the side of it, but this would be nice, too. + |
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<freud>So, you want to erect a massive tall pointy thing which pumps liquid out of its tip?</freud> |
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Whatever the usefulness of this idea in actually providing low cost air cooling, there is the added bonus of creating a new urban sport. |
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I can picture the free running, base jumping types riding the water down the building to land in the collection trough at the base. |
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Okay, I've got it. A double glass layer, with the outer raised far enough that water from the inner doesn't splash up to it. Design automated squegees that clean the inner on a regular (hourly?, daily?) basis. Put a solar powered absorption chiller at the top to act as a condenser. |
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Then locate the building on the coast somewhere with plentiful salt water. The squegees clean any percipitated salt crystals off the inner glass, the chiller provides a ready supply of potable water, and the hyper concentrated brine removed every day is left in a pond to evaporate and produce sea salt. |
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If you wanted to, you could also mount tropical plants in planters on the inside of the outer wall, producing oxygen and possibly food, continously watered by the condensation that forms in their own shadow. |
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Now they could have incorporated this into "The Shard" (linky) |
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Now they could have incorporated this into "The Shard" (linky) |
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Now they could have incorporated this into "The Shard" (linky) |
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Some very nice ideas
But bankers that are clowns or morons, in 2011 that’s bad taste. |
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This looks to me, like an inside out power tower.
in witch case a few well placed wind turbines and you get all of your pumping done, and a bit of electricity generation. |
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a power tower
1) pump water up to the top of a very large tube.
2) spray the water inside, it evaporates, that cools the air.
3)the cold air sinks, and turnes fans as it flows out at the bottom. |
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there will be quite a down draft, and out flow around this tower. |
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