Product: Air Conditioner
Ice Pond Refinement   (+14, -2)  [vote for, against]
So simple! So elegant! and yet not widely used. Here is an idea to make ice ponds more commercially attractive.

The ice pond is not a new idea. It's based on the fact that ice, harvested during the winter and stored cheaply, takes a surprisingly long time to melt, and so can be profitably sold in summer. This used to be big business in the 1800's, with New England ice shipped as far away as Calcutta. (First link).

More recently it's been proposed as a cheaper way to air- condition large buildings: set up a ski-resort-type snowmaking machine in winter, to make a big pile of snow, cover it in cheap insulation, and, in summer, trickle water through it, yielding a supply of chilled water for air conditioning. This has been piloted successfully (see links 2 & 3).

Around here, shopping malls & such have really large parking lots. In winter, they're kept clear of snow by plowing -- often with bulldozers, backhoes & the like. Huge piles of snow sit at the edges of these lots long into spring, protected by their low surface-to- volume ratio.

I propose that pits be dug at these lots, and the snow plowed into these pits. A diversion from the chilled-water circuit of the mall's air conditioning plant should be run to a heat exchanger in the pit (a skein of PVC pipe might work, but if not, more sophisticated systems are available (see link 4)). Fencing would be needed, and also, I think, a sump or bilge with connection to the storm drains. Neither capacity nor reliability need be all that high: the system's only intended to supplement conventional air conditioning, reducing electricity expenditures.

The system is perhaps best suited to airports. Wide, straight runways are easier to plow; specialized snow-moving equipment is already in use, on an aggressive schedule; there's no sand or salt added to the snow; there's plenty of surrounding land for ice ponds; there's a large centralized air-conditioning plant nearby; the plant is at ground level. Also, airports might want a conspicuously "green" project for PR purposes to offset carbon footprint embarrassment.
-- mouseposture, Jan 10 2010

Big business http://www.amazon.c...Story/dp/0786886404
_The Frozen Water Trade_ Gavin Weightman, Hyperion, 2003 [mouseposture, Jan 10 2010]

Yes, that's the title http://search.barne...hee/e/9780374520083
"Ice Pond" in _Table of Contents_ John McPhee, Farrar, Straus and Giroux, 1986 [mouseposture, Jan 10 2010]

Online (but read the book. Really. You won't regret it.) http://en.wikipedia.org/wiki/Ice_pond
[mouseposture, Jan 10 2010]

What's the opposite of "radiator?" http://images.googl...n%26sa%3DN%26um%3D1
[mouseposture, Jan 10 2010]

"New Japanese airport will be cooled with snow" http://green.yahoo....oled-with-snow.html
Kudos mouseposture, I stumbled upon your idea in practice :) [EricNutsch, Jun 15 2010]

Yes.
-- MaxwellBuchanan, Jan 10 2010


I'm wondering how much better or worse pykrete would perform. The ultimate goal here is heat transfer at the right time, so pykrete's insulating factor might not be a good thing... Maybe as an initial liner?
-- RayfordSteele, Jan 10 2010


This is interesting. I hate those mountains of snow they leave sitting in mall parking lots and such. They are dangerous. You can't see past them when trying to leave, it can get really bad quickly. If this were truly doable, and sustainable, then I think it's a wonderful idea.
-- blissmiss, Jan 10 2010


[RayfordSteele]//Pykrete// Hmm, interesting stuff. What could sound sillier than a wooden aircraft carrier? An aircraft carrier made of sawdust and water.

I like the idea of using -- year round, in a temperate climate -- a construction material which must be kept below freezing at all times, and perhaps I've inadvertently invented an excuse for that. I'd been pondering the problem of keeping the snow in contact with the heat exchanger, as the pile slumped, with melting. Perhaps, if the snow were mixed with sawdust, it could form a partly self-supporting structure. However, you'd need to recover and recycle the sawdust, reducing the simplicity of the idea.

[blissmiss] Dangerous *and* ugly. By late March, they're *black*
-- mouseposture, Jan 10 2010


If I understand this right, the snow is only useful when the air conditioning is on 'chill' mode rather than 'heat' mode. If a shopping mall or airport is to be kept at say 18 deg C, then allowing for heat generated by people and plant inside the building, I would guess the 'chill' mode wouldn't be required until the average outside temperature was around 12 deg C. Shirley by this time the snow would have melted, even if insulated? I guess it depends on the local climate, speed of season-shift, and volume of snow. I know I was surprised at how quickly my snowman melted this year even though the temperature was hovering around the 3 deg C mark by day and below freezing by night. Mind you, the only insulation he had was a tartan scarf.
-- stupop, Feb 26 2010


Build the parking lot over top of a series of Bobcat (small tractor) sized tubes, with an open slot at one end. Plow the snow into the slot. Use a bobcat to pack the snow into the far end of the tube. Each tube has a single heat exchanger loop in it's floor, along with a drain. It also has very high R value insulation all the way around. Every time the air temperature is above freezing, cap the end of the ube with several feet of insulation. By the end of a moderately snowy season, you have full tubes which should last all summer if they aren't used, and be a decent supplement to AC. I like it.
-- MechE, Feb 26 2010



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