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Making Ice Without Electricity
j-beda writes "Time Magazine is running an article telling us how Dave Williams is trying to make ice for third-world applications using the Hilsch-Ranque vortex-tube effect (first developed in 1930 by G.J. Ranque), where swirling air is split into hot and cold components." The method is horribly inefficient but Williams is hoping it could yield helpful results in areas where electricity is really not an option.
1. Wind turbines used to create it and charge batteries at the same time.
2. Solar cells used to create it and charge batteries at the same time.
Inefficiency is in the eyes of the beholder.
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How can you rotate anything without moving parts???
10000000 rpm could be acheivd with mules and huge gears?
To make that "high rate of rotation (over 1,000,000 rpm)." Better use the ice on your legs after.
If you press a gas into a cylinder with a specific angle, it starts to rotate at a very high rpm. Here is the construction.
Please RTFM first.
My mothers house has 2 ammonia Air Conditioning units built in the mid to late 40's they were "Overage" for a bank and made their way into my grandfathers new home, since it is a hot water heated house its great, let me tell you these things will even chill the upstairs of the house , at 2000 ish square feet to push cold up is not a bad trick, the volume they output is the key.
:) Designed well, and built like German tanks...
The funny part ? They still work flawlessly, and have not been serviced since at least 1977 ( In know this for a fact as thats when my grandad passed away)
Their electric consumption is actually minimal, running both all month equates to about a 60$ electricity increase. Unreal if you ask me, I kept thinking we were on an electric budget the first summer I fired em up in 20 years as it was way to hot for my grandma without air so I told her I would cover the bill. it never went up....
The beauty is these units will spill the ammonia outsie through the exhaust should the coils ever rupture (I doubt it since they are about 1/8 in thick copper
The ancient egyptians did the same. In the desert.
If you build a solar reflector, but only employ it at night the items inside will become cold, and can attain temperatures below freezing.
Doesn't work as well on cloudy nights (you are essentially 'beaming' the heat out into the great heatsink called space) and it has to be well insulated from the environment around it (ground, air, etc).
-Adam
For an interesting look at a time before refrigerators when ice was cut from lakes in North America and shipped around the world, read Gavin Weightman's book The Frozen Water Trade.
and let's ignore that it's worthless.
I make ice and keep things cold EVERY time I go camping without electricity. in fact I make a fire to make things cold.
that type of freezer/fridge has been around for decades and are pretty efficient now compared to electric units.
I use maybe 10 pounds of Propane to run my RV fridge for 3 months straight.
I'm all for inventing new ways of doing it, but to "help the poor in africa" is not the way to try out new stuff.
give them a fridge with a coil plate they can build a fire under or will allow an oil lamp burner to keep it running (yes this works) and use that old tech that simply works.
Do not look at laser with remaining good eye.
That is exactly what I was thinking. If you need compressed gas for it to work where is the enegry coming from to compress it? I doubt any hand operated device will produce any results. If the system were engine driven and the vortex tube is so inefficent, then why not just use an engine to drive a compressor? Better yet run a generator to run a real more efficent refrigeration system? Maybe even a solar array to do away with fuel costs. the only benefit this presents is the elimination of moving parts so it is cheap and easy to produce. but then again getting compressed gas requires a device with moving parts that will be more costly and wear out over time.
And on another note there is a method of refrigeration that does not use any moving parts and works on gas(or anything that will burn I guess). Maybe this can also work with a solar mirror array?
If someone wants to do something really interesting for the third world, make an adsorbtion freezer using solar concentrators for the heat source.
And while you're at it, a solar concentrating mirror (or foil arrangement), without a greenhouse-forming glass layer, pointed at a cloudless night sky, makes ice REALLY well.
The night sky (absent clouds and above the atmosphere) is four degrees absolute - and it's not THAT much warmer from ground level even with the mostly sub-zero greenhouse gas layers floating above. With mirrors or foil to redirect the light/infrared so that the container of water (or coolant) "sees" night sky on all (or most) directions and reasonable shelter from air currents, a container's black-body equilibrium temperature is far below freezing. It heads for that temperature quite quickly if it is painted a dark color.
People have been making ice on calm desert nights using this principle for centuries.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
No wonder they stopped making them. They were putting plumbers and stores out of business with durable and reliable air conditioners
You jest, but truth is stranger than fiction...
During the first half of the nineteenth century, an enterprising Boston chap by name of Frederic Tudor made his name - and his fortune -harvesting enormous chunks of ice from frozen lakes in Massachusetts, packing them into sailing ships insulated with sawdust (supplied by the Maine timber-mills), and exporting them around the world. By the time artificial refrigeration marked the end the "frozen water trade" in the mid 1800s, they were sending 100-ton shipments of ice as far afield as the Caribbean and Calcutta.
The whole story is told in Gavin Weightman's The Frozen Water Trade, if you want to know more.
-- Open Source: It's mad, but you don't have to work here to help.
After I got out of the Army and before I went to college I used to sand-blast paint off bridges for the county. In our setup we wore a hard helmet which was presurized to keep the toxic dust out, heavy metal pigmented paint and silica dust and the helmet were persurized through a demon tube, an other name for the Ranque-Hilsch vortex tube. this kept us pretty cool while working in 90 degree heat wearing heavy gloves and two sweatshirts for padding. The set up used no electricity, but the diesel engined air-compressor probably would have put out 120KW if hooked to a generator instead of a compressor.
If I wanted to make ice in a place like back-woods Hati; I think a solar-collector connected to a couple stirling engines would be the way to go, one engine makes kinetic energy from the solar heat, the second refirgerates form the kinetic input of the first engine; sterling refrigerators are capable of acheiving cryogenic temeratures
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