Mongolia Wants To Use Artificial Glaciers To Cool Capital

phaedrus5001 wrote in with a story about an unusual plan to regulate the temperature of Ulan Bator, the capital city of Mongolia. The article reads: "The city of Ulan Bator will attempt to capture some of the cool winter temperatures in huge ice blocks that will slowly melt over the summer and cool down the city. The aim is to build artificial ice shields — or 'naleds' — that occur naturally in far northern climates and can grow to be more than seven meters thick. They grow when river water pushes through cracks in the surface of the ice during the day and then freezes to add an extra layer of ice when night falls. Engineering consortium EMI-ECOS will try to replicate this process by creating holes in the ice that is forming over the Tuul river. This will be repeated over and over again until the ice is much thicker than it would be if left alone."

With an average high of about 70 degrees...

[Anonymous Coward]

... in the summer, I'm not sure they need that much cooling. (That's slightly over twenty degrees for those of you who don't speak proper American).

Re:With an average high of about 70 degrees...

[Anonymous Coward]

It's basically the same climate as Winnipeg, and we use air conditioning for a good chunk of the summer. the average high is around 20C, but that's because it alternates between 10C and 30C through most of the summer. Also, northern towns just aren't equipped to deal with heat waves - nobody has swimming pools, and only about 70% of homes have air conditioning. If the temperature is over 35C, pretty much everything shuts down. On the other hand, throw us a week of -40, or a foot of snow and it's life as usual.

Re:Very Interesting

[Anonymous Coward]

They use a similar technique to cool the Kidd Creek mine: http://blogs.agu.org/martianchronicles/2011/08/01/9800-feet/

"We learned during the mine briefing video that part of the cooling system actually involves opening up huge caverns near the surface during the winter and forcing the bitter cold air through while spraying water. This coats the tunnels in thick layers of ice. Then, during the summer, air is passed through these cavernous iceboxes before being sent down to the bottom of the mine."

Re:Very Interesting

[inpher]

I suppose we could compare this to Ice Hotel in northern Sweden where they take 10 000 cubic meters of ice from the Torne River [wikipedia.org], since the flow of the river is about 370 cubic meters per second this means a disruption of slightly less than 30 seconds that melts back over the course of a few months. Tuul River [wikipedia.org] that will be used for this seems like a river of comparable size (longer, but likely a slower flow). If the Ulan Bator experiment will produce use ten times as much ice (100 000 cubic meters) and it will take about 120 days for it to melt back into the river it would be at a rate of: about 833 cubic meters per day, or about 34 cubic meters per hour,> or less than 600 liters per second.

Now, for that to be a significant difference compared to normal flow during these months average flow must be if we say that anything less than 5% change is no big deal (I do not know what changes the river can actually deal with before botched migrations or flooding becomes a risk) for the river 12 cubic meters per second.

If the river is flowing at 30 cubic meters per second and 5% change as a threshold then Ulan Bator could conceivably take 300 000 cubic meters of ice, let it melt during 150 days (april, may, june, july, august) and still not make a difference in the normal water flow.

Re:With an average high of about 70 degrees...

[ackthpt]

Yeah, if their summers are that mild, it doesn't seem necessary. But then again, as a proof of concept, it has to happen somewhere the winters get very cold but the summers could stand to loose a little bit of heat. If they're too cold during the summer, they can break up the ice.

Can't cite a source, but I do believe our bodies become accustomed to the cycles of a climate. Spending most of winter, for most of my life in colder climes I visited Athens, Greece a couple times in Winter. After a few days of 70 F/ 20 C I was miserable and felt overburdened by the heat. I booked flight for Geneva and when I stepped onto the tarmac in Switzerland, I opened my jacket to let the cool 10 F / -10 C air in. It felt good. I believe it was an example of a metabolism which was accustomed to generating body heat couldn't cope well with warmer weather in the middle of Winter.

With glaciers and Winter in decline across the world perhaps cities are noticing an increase in heat.

Smaller Scale Prescedent

[bill_mcgonigle]

There was a story a few years back about a university (Scandinavia?) that spends the winter pumping water to freeze into a giant block on one part of campus, and then come summer, they just pump coolant through the block as it melts.

Pumping water is apparently much cheaper than traditional cooling.

Re:Smaller Scale Prescedent

[afidel]

Ice block cooling is fairly common in commercial and datacenter cooling systems in areas where there is a large discrepancy in pricing between peak and off peak electric prices. Also it's rarely water that is used as the heat transfer media, it's usually glycol as using water would result in clogged pipes because it would freeze in the portion of the pipe in contact with the ice block.

ice pond

[Anonymous Coward]

https://en.wikipedia.org/wiki/Ice_pond
An ice pond is a large volume of ice or snow produced and stored in the winter to be used for cooling/air conditioning in the summer. The best known experiment is the 'Princeton ice pond' by Ted Taylor in 1981. He then convinced the Prudential Insurance Company to use a bigger pond to provide air conditioning for a larger building.