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Making Ice Without Electricity

ScuttleMonkey posted more than 9 years ago | from the old-science-becomes-new-again dept.

Science 608

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.

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Hrm. (5, Funny)

grub (11606) | more than 9 years ago | (#13540458)


In Winnipeg we just leave water outside for a few minutes.

In Soviet Russia... (3, Funny)

Anonymous Coward | more than 9 years ago | (#13540496)

The water leaves YOU outside for a few minutes.

In Soviet America... (4, Funny)

Anonymous Coward | more than 9 years ago | (#13540726)

The President leaves you in the water outside for a few days.

Re:Hrm. (1)

Alex P Keaton in da (882660) | more than 9 years ago | (#13540512)

Yes, but will it make Vanilla Ice...?
Rollin', in my 5.0 with the top left back so my hair can blow...

Re:Hrm. (1)

BigDumbAnimal (532071) | more than 9 years ago | (#13540561)

No, in Canada you get this:

'Tective man he say, say Daddy Me Snow me stab someone down the lane
A licky boom-boom down...

Re:Hrm. (2, Funny)

Surt (22457) | more than 9 years ago | (#13540605)

Fantastic, we'll just pack it in dry ice (to keep it cold) and ship it to third world countries. Problem solved!

Re:Hrm. (1)

nine-times (778537) | more than 9 years ago | (#13540711)

Maybe when it gets there, we should just store it in some air-conditioned warehouses?

Venetian Snares was right then? (1)

mindaktiviti (630001) | more than 9 years ago | (#13540666)

Re:Venetian Snares was right then? (1)

grub (11606) | more than 9 years ago | (#13540697)

Not a shithole but it's cold in the winter :) I've been looking for that album for a while after hearing about it actually.

Re:Hrm. (3, Funny)

peculiarmethod (301094) | more than 9 years ago | (#13540673)

In San Diego, we just take our beer to the beach and talk to the nearest bikini. Instant freeze.

Third World? (1)

cashman73 (855518) | more than 9 years ago | (#13540470)

Making ice for the third world? Heck, this could come in handy in a place like New Orleans, too!

Re:Third World? (1, Interesting)

VATechTigger (884976) | more than 9 years ago | (#13540532)

hell, they would just shoot at you when you tried to give it to them. Perhaps they like cold Hurricanes (the drink) enough to put the guns away and accept the help...

The big question is... (5, Insightful)

geeber (520231) | more than 9 years ago | (#13540558)

According to the article this method doesn't require electricity. Then where does the energy to generate the required volume of compressed air come from? Hand pumps?

Re:Third World? (1)

irving47 (73147) | more than 9 years ago | (#13540588)

"You imply disparity where none exists"
-Borg Queen. Star Trek First Contact

Oh go ahead. With everything you've got.

Re:Third World? (1)

MikeFM (12491) | more than 9 years ago | (#13540729)

Like they said.. third world.

New Orleans looks pretty third world to me. (0, Offtopic)

Colin Smith (2679) | more than 9 years ago | (#13540736)

If I didn't know better i'd have sworn the pictures were coming from somewhere in Africa.

Looking at other areas in the US, It's interesting to note just how much of America is really poor.

 

You'll have to pedal really fast... (1)

nathan s (719490) | more than 9 years ago | (#13540472)

to make that "high rate of rotation (over 1,000,000 rpm)." Better use the ice on your legs after.

Re:You'll have to pedal really fast... (1)

RapmasterT (787426) | more than 9 years ago | (#13540709)

You'll have to pedal really fast...high rate of rotation (over 1,000,000 rpm).
It's not that bad, you just have to adjust the gearing. A front gear the size of a mall parking lot should just about do it.

Clean water first??? (5, Insightful)

technoextreme (885694) | more than 9 years ago | (#13540480)

How about we try and ensure we give them clean water first. The only use for this is in refrigerators and keeping food fresh.

Re:Clean water first??? (0)

Anonymous Coward | more than 9 years ago | (#13540650)

And let's make sure we pump the last oil drop before we research other energy sources.

Re:Clean water first??? (5, Insightful)

Khashishi (775369) | more than 9 years ago | (#13540652)

freezing water causes a lot of impurities to come out, so these are not contrary goals. Keeping food fresh is pretty important, though.

Re:Clean water first??? (1)

RajivSLK (398494) | more than 9 years ago | (#13540707)

Dude, you have a really messed up view of the third world (which is most of the world btw).

Re:Clean water first??? (1)

peculiarmethod (301094) | more than 9 years ago | (#13540751)

or keeping samples of biological material fresh for discerning things like the cause of an outbreak, or criminal guilt. it would make researchers jobs easir if they didnt have to bring a freakin fridge to a site.

Like New Orleans? (0, Troll)

xxxJonBoyxxx (565205) | more than 9 years ago | (#13540481)

"Williams is hoping it could yield helpful results in areas where electricity is really not an option."

Like New Orleans?

Make or Sell? (1)

conner_bw (120497) | more than 9 years ago | (#13540488)

This guy is in Engineers Without Borders [ewb-usa.org] so it appears his intentions are good, but what's the deal? How much would it cost to make one of these devices and who's fronting the cash?

Re:Make or Sell? (1)

Sialagogue (246874) | more than 9 years ago | (#13540574)


Well clearly Tanqueray is fronting the cash, and as long as it costs less than fifteen locals on Gilligan generator bikes hooked to a Sub-Zero, they're going ahead with it.

Re:Make or Sell? (1, Informative)

Anonymous Coward | more than 9 years ago | (#13540732)

This has already been dealt with in a semi-cost-effective manner:

http://www.homepower.com/files/solarice.pdf?search =solar%20ice [homepower.com]

The article is a bit dated, so the costs are undoubtedly off, but it's got to be one of the lowest cost solutions for this particular problem.

Could be useful (2, Funny)

Mister sharkbot (913897) | more than 9 years ago | (#13540489)

useful indeed. (10000000 rpm could be acheivd with mules and huge gears?)

Re:Could be useful (1)

denis-The-menace (471988) | more than 9 years ago | (#13540563)

At that speed, a centrifugical fan with a too-small intake could cool down things more efficiently with the venturi effect.

Already done! (4, Funny)

DogDude (805747) | more than 9 years ago | (#13540493)

I think that we all know that it's already been tried, and baaaad things happened as a result:
http://www.imdb.com/title/tt0091557/ [imdb.com]

New definition of "moving parts" (1, Insightful)

hesiod (111176) | more than 9 years ago | (#13540497)

From the Wikipedia link (http://en.wikipedia.org/wiki/Vortex_tube [wikipedia.org] ):
> The vortex tube, also known as the Hilsch-Ranque vortex tube, is a heat pump with no moving parts
> ressurized gas is injected into a specially designed chamber and accelerated to a high rate of rotation (over 1,000,000 rpm).


How can you rotate anything without moving parts???

Re:New definition of "moving parts" (5, Informative)

SiliconEntity (448450) | more than 9 years ago | (#13540524)

How can you rotate anything without moving parts?

The gas moves into the chamber under pressure. The chamber is shaped to send the gas into a whirling vortex. Then the hot molecules go one way and the cold ones go the other. But I think it takes very high pressures to produce the required speeds.

I know nothing about this... (1)

nathan s (719490) | more than 9 years ago | (#13540538)

But I presume that the gas is injected into the side of the chamber at an angle, so that it rotates around due to collision with the rounded walls. Not too mysterious. I'm just wondering about that high rate of rotation.

Re:New definition of "moving parts" (1)

hesiod (111176) | more than 9 years ago | (#13540562)

Ach, stupid me... The air rotates, not the drum... but then, how would you "rotate" air to such obscene speeds? It mentions a compressor, but if I had the energy to operate a compressor, why wouldn't I have the energy to to run a freezer?

I thought of that right after posting, yet despite "excellent" karma, I still have to wait 5 minutes before posting...

First Prime Factorization Post (1)

2*2*3*75011 (900132) | more than 9 years ago | (#13540499)

1930 = 2*5*193, a boring factorization.

Dr. Brown (2, Funny)

3CRanch (804861) | more than 9 years ago | (#13540504)

Didn't Dr. Emmit Brown invent something like this back in 1845 or so? You know, shortly before Marty arrived...

Re:Dr. Brown (2, Informative)

petabyte (238821) | more than 9 years ago | (#13540616)

Ok, not to be pedantic, but it was 1885 - you know, 100 years before the first movie which was 1985.

He also perfected that machine that made breakfast automatically in the morning which was a mess when he tried it in 1985.

Oh and yeah, a time machine powered by steam but thats the only part of the movie I didn't find plausable ...

Re:Dr. Brown (2, Informative)

OverlordQ (264228) | more than 9 years ago | (#13540718)

No the time machine wasn't powered by steam (if you're referring to BTTF:III), the whole steam loco was used to get the car up to the required 88 miles per hour, not to generate the power for the flux capacitor.

Re:Dr. Brown (0)

Anonymous Coward | more than 9 years ago | (#13540640)

That would be 1885.

Of course.... (0)

Anonymous Coward | more than 9 years ago | (#13540509)

TIME forces a subscribtion to read the rest of the article.

Re:Of course.... (1)

coolGuyZak (844482) | more than 9 years ago | (#13540535)

I believe thay might have moved it from non-subscribed to subscribed space in response to the /. effect. Not sure... but it would explain why the first page is a re-direct.

Good one, Dave! (1, Funny)

Anonymous Coward | more than 9 years ago | (#13540515)

Dave Williams is trying to make ice for third-world

Turning the rare drinking water they've got into solid ice, eh?

Ice doesn't have to be clean to be helpful (1)

brokeninside (34168) | more than 9 years ago | (#13540629)

If one were, say, to be carting fish from the ocean to the market in the next town over, you don't need to make your ice from potable water. You can put the ice in the bottom of your cart, put down a tarp, and load the fish on top of that. The fish arrives much fresher than it would otherwise. Such uses of ice would vastly improve life in many parts of the world.

Re:Good one, Dave! (1)

jasongetsdown (890117) | more than 9 years ago | (#13540699)

if the ice is from water condensed out of the air like the ice that builds up on outdoor tanks of liquid hydrogen, then you're making clean ice without using up clean (liquid) water.

Let's be honest here (-1, Flamebait)

rudy_wayne (414635) | more than 9 years ago | (#13540526)

"in areas where electricity is really not an option."

Not an option because ...? because theylack the basic intelligence necessary to do something that others have been doing for more than 100 years?

Re:Let's be honest here (1, Insightful)

Anonymous Coward | more than 9 years ago | (#13540602)

Yea right, asshole. Let's go with this scenario, where we:

Take away all of your food, clothing, and money.

Take away your education and literacy.

Leave you starving in unarable land.

Now build a generator! Good luck!

Seriously. You are an asshole. Do you think people in third world countries have distinctly different brains? For the most part, their societies were either screwed by outside influences (see African colonialism), or they simply reached a point of equilibrium where technology was not required. (Native Americans.)

This doesnt make them stupid, but it sure as fuck does make you look that way.

Asshole.

Re:Let's be honest here (1)

mblase (200735) | more than 9 years ago | (#13540630)

Not an option because ...? because theylack the basic intelligence necessary to do something that others have been doing for more than 100 years?

Um, no. Where in the world did you get that interpretation?

It's because generating electricity means you need to build a turbine, or dam a river, or something along those lines along with having enough copper wire and other necessities to store, transfer, and transform the current. And there are plenty of places on this wide blue ball we call Earth where those things do not yet exist.

mod parent down (1)

tehwebguy (860335) | more than 9 years ago | (#13540635)

you are an idiot.

do you make your own electricity?

Re:Let's be honest here (1)

dolphinling (720774) | more than 9 years ago | (#13540639)

No, because they lack the fossil fuels.

Re:Let's be honest here (0)

Anonymous Coward | more than 9 years ago | (#13540654)

Or perhaps they don't have the infrustructure or tools to do it. Couldn't be anything like that could it? Must be some prejudice on the part of the writer. Why don't you go up into mountains and make enough electicity to power a refrigerator. I'll even let you use the tools in your car. What? Can't do it? You must because you lack the necessary intelligence to do something everyone does with the flip of a switch.

Re:Let's be honest here (0)

Anonymous Coward | more than 9 years ago | (#13540658)

"because theylack the basic intelligence necessary to do something that others have been doing for more than 100 years?"

What exactly are you trying to imply the parent is saying?

Could it not be as easily assumed that the parent means it's really not an option because they don't have the capital to invest in the inftrastructure?

Do you own a jump to conclusions mat? You know, it's like a mat that has different conclusions on it that you can...jump to. :|

Re:Let's be honest here (1)

Ascoo (447329) | more than 9 years ago | (#13540723)

"because theylack the basic intelligence necessary to do something that others have been doing for more than 100 years."

Knowing how to do something, and having the resources to do it isn't the same. While it may seem trivial to those in technologically advanced countries, the production of electricity in useful quantities isn't easy. Not everyone has access to the same resources that some of us take for granted. This is especially the case in countries where there is a huge diachotomy between the rich and poor. And by resources I'm not just referring to physical machinery and fuel, but education as well. And on top of that you occasionally have oppressive regimes trying to keep the poor in dependent situtations so that the rich won't lose their labor force. okay, I'm starting to get off topic now.. All I'm trying to say is it would be fallacious to assume that the only reason that certain populations don't have electricity is because they're not intelligent enough.

I read TFA, and... (5, Informative)

arhines (620963) | more than 9 years ago | (#13540529)

... Time really needs to get its story straight with regards to scientific reporting. This method is a) not innovative b) not practical and c) REQUIRES SIGNIFICANT ENERGY INPUT. Vortex tubes have been around forever, and they are not some form of perpetual motion. It is a well-understood effect, and one which does not violate any of thermodynamics. You put in a lot of energy via compressed air, and get output in the form of a thermal differential. The key point is that you need a lot of high pressure input...where is this going to come from? Electricity. Unless you use a combustion engine to turn the crank on a compressor, in which case that's your energy source. What are villagers in rural india going to do? Blow really hard through the tube?

Re:I read TFA, and... (1)

Znork (31774) | more than 9 years ago | (#13540578)

Instinctively I'd consider the possibility of using a stirling engine before trying this method.

Re:I read TFA, and... (0, Offtopic)

RichMan (8097) | more than 9 years ago | (#13540633)

Question, would companies like slashdot level traffice sent to their pages, especially if they are looking to get subscriptions?

Could this be a new spam technique, attempting to get pay articles referred to by popular web sites?

This article is silly. (1)

MrAnnoyanceToYou (654053) | more than 9 years ago | (#13540533)

Because it's a Time subscriber only article. There's no really interesting discussion in the first ten posts because, well, noone can know anything or RTFA. Why do it this way?

??? = electricity = ice: More efficient (1)

fuzzy12345 (745891) | more than 9 years ago | (#13540537)

Where, oh where would it be more efficient to use this crazy scheme than to generate electricity by various conventional means, then make ice with it?

Re:??? = electricity = ice: More efficient (0)

Anonymous Coward | more than 9 years ago | (#13540594)

Shhhh! That would be too logical.

Re:??? = electricity = ice: More efficient (1)

clueless123 (643205) | more than 9 years ago | (#13540685)

Electricity itself does not makes the ice, it is the gases being compressed and decompressed on opposite chambers that transers the heat from one side to the other , (leaving the inside cold and the outside hot) So, you could (been done before) attach a bicycle to the pump, and do the pumping by pedaling, or even easier, most non-electricity places in the world use kerosine run fridges... basically generating ice from fire :) The basic idea is this: You heat an amonia solution to its boiling point on a sealed container with. it aquires great pressure, then let it escapes tru a pinhole into a radiator. when the amonia gas expands, it actually consumes heat, (produces cold) the trick, is to have the radiator inside the icebox, and the pump on the outside. You can do this with any gas.. amonia solution, just happens to be better at it ..

What's the point? (1)

conJunk (779958) | more than 9 years ago | (#13540541)

According to TFA, it uses 35x the amount of energy as an electric freezer. That's a lot of juice. And you need that juice to move the compressed air around (right?) You can't just hook a tube up to a windmill and magically have ice come out.

It seems entirely counter productive to me. This kind of phenomenon seems like it's usefull in situations where you aren't worried about energy cost, but mabe some other concerns (like rapidly cooling something?)

Seems kind of pointless. (1)

LWATCDR (28044) | more than 9 years ago | (#13540543)

1. It is very inefficient.
2. You still have to have the energy to compress the air.
3. High pressure air systems do not take abuse well and can be very dangerous.
4. This thing will be noisy as all get out.

Yea he says that you could use wind, water, and or solar to power this thing but you could do the same with conventional cooling systems as well. Solid state cooling systems would be far more sturdy and a conventional compressor based system far more efficent.

Re:Seems kind of pointless. (1)

RobertB-DC (622190) | more than 9 years ago | (#13540682)

1. It is very inefficient.
2. You still have to have the energy to compress the air.
3. High pressure air systems do not take abuse well and can be very dangerous.
4. This thing will be noisy as all get out.


You forgot:

5. ???
6. Profit!

I think Step 5 goes something like this:
To continue reading the complete article, login or subscribe below and get free instant access. Get 6 issues of TIME for only $1.99

Kapiche?

10000000 rpm (1)

paulwallen (825524) | more than 9 years ago | (#13540545)

10000000 rpm..? My deskstar harddrive spins that fast.

Why not just make electricity? (5, Funny)

mikew03 (186778) | more than 9 years ago | (#13540547)

If you can spin something at 1,000,000 RPM why not spin a copper coil inside a magnetic field and make electricity instead? Quite useful stuff I've heard.

Re:Why not just make electricity? (5, Funny)

RapmasterT (787426) | more than 9 years ago | (#13540620)

If you can spin something at 1,000,000 RPM why not spin a copper coil inside a magnetic field and make electricity instead? Quite useful stuff I've heard.
BINGO!!! We have a winner of the "Find the Logic Hole in the Seemingly Reasonable Idea" game!

There's a reson why electicity is a freakin' universal component of modern societies people. It's EASY to produce, so easy that's it's just about goddamn trivial since there's dozens of different ways to go about it, and NONE of them involve ridiculously ineffcient and complex methods like "ice without electricity" does.

Hell, why not work on "masturbation without enjoyment" too, that should be just as useful.

Re:Why not just make electricity? (0)

karnal (22275) | more than 9 years ago | (#13540664)

I cry every time I masturbate.

Why are you looking at me like that?

Re:Why not just make electricity? (0)

Anonymous Coward | more than 9 years ago | (#13540735)

why are you crying?

Re:Why not just make electricity? (1)

VATechTigger (884976) | more than 9 years ago | (#13540733)

Hell, why not work on "masturbation without enjoyment"..... Hrm, if its spinning at 1,000,000 RPM it will either be masturbation without enjoyment, or the best thing ever invented.......

Eletricity is always an option (1, Insightful)

Anonymous Coward | more than 9 years ago | (#13540548)

In the few areas there are no eletricity you can always use a generator, powered by diesel or gas. That's the way people do here in the Amazon jungle and works fine.

This guy is basically clueless.

Compressed Gas in the 3rd world? (2, Insightful)

Anonymous Monkey (795756) | more than 9 years ago | (#13540556)

I read the article, and the wikipeda entry, and am left with a question. Without electricity and fule how do we get the compressed gas to run this thing?

Re:Compressed Gas in the 3rd world? (1)

wtansill (576643) | more than 9 years ago | (#13540647)

I read the article, and the wikipeda entry, and am left with a question. Without electricity and fule how do we get the compressed gas to run this thing?
Flatulence.

hmm... (1)

quark007 (765762) | more than 9 years ago | (#13540557)

To continue reading the complete article, login or subscribe below and get free instant access. Get 6 issues of TIME for only $1.99.

There Ain't No Such Thing As A Free Lunch.

Wasting Away Again (1)

Stanistani (808333) | more than 9 years ago | (#13540560)

Sounds like the sort of invention Jimmy Buffett (as opposed to Warren Buffett) might be interested in.

Margaritaville without electricity...

Why not gas absorption? (1)

dsci (658278) | more than 9 years ago | (#13540564)

Ammonia based gas absorption refrigeration works well with heat source, such as kerosene [nh3tech.org] or propane [lpappliances.com] . I often thought about ways to focus solar radiation to do the trick, as well.

There was even a pretty cool movie [imdb.com] made based on it.

Re:Why not gas absorption? (1)

johnny cashed (590023) | more than 9 years ago | (#13540703)

Yes, there has been an article on the homepower website on a solar powered ammonia based ice maker. The one in the article was constructed in Alabama, and would use solar heat to drive the ammonia into an absorbant, then at night, it would freeze water to make ice. Very scalable, the only nasty part about it is the ammonia. And that is fine as long as it is in a sealed system (which this was). No moving parts, very simple construction (if I recall correctly). If only knowledge was shared (and easy to find) more often.

Re:Why not gas absorption? (1)

clueless123 (643205) | more than 9 years ago | (#13540754)

look at : http://www.electrolux.com/node442.asp [electrolux.com] Had one of those at home when I was a kid, and I think they still sell them. You could do the solar radiation trick.. but they are very picky about having a steady heat source (day and night)

Money-Grab (0)

Anonymous Coward | more than 9 years ago | (#13540570)

Time probably did it to cash in on the slashdot traffic. Post it for free until there is a decent amount of money to be made and then close it off to the public. Pigs

Misleading title (2, Funny)

Guppy06 (410832) | more than 9 years ago | (#13540572)

Want ice without electricity? Drive the compressor with a small diesel power plant.

evaporative ice (0)

Anonymous Coward | more than 9 years ago | (#13540576)

Ancient Egyptians created ice by fanning wide shallow ponds of water in caves. The thin skin of ice that would form would be collected in insulating feather and run down to the Pharaoh.

What's the big deal? (3, Informative)

Gigabit Switchman (16654) | more than 9 years ago | (#13540583)

Why try to develop something entirely new, with the resulting time and money requirements? A few solar cells + Peltier coolers + some insulation and an ice tray. Yes, Peltiers are inefficient... but they're solid-state, at least, which I think ought to do for remote areas as far as durability. I would think you could assemble a decent mini-freezer out of things portable enough to carry anywhere:

1) Flexible solar panels (less efficient but more portable than glass)
2) A handful of Peltiers... they're pretty small
3) A couple of cans of "Great Stuff" spray-in insulation, or cans of A-B component expanding insulation

One of my friends went to Peru to assemble a non-electric solar water purifier, and anything they couldn't carry on their backs on 30-mile-a-day hikes for a week didn't go. Now that's a design constraint!

Re:What's the big deal? (1)

WillAffleckUW (858324) | more than 9 years ago | (#13540719)

In fact, ice used to be shipped in barges, packed in sawdust, from Northern Europe all the way to Egypt.

Sometimes, low tech is best.

Easier ways to make ice in electric-poor areas (2, Interesting)

WillAffleckUW (858324) | more than 9 years ago | (#13540596)

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.

It doesn't take a genius to figure this one out... (1, Informative)

Anonymous Coward | more than 9 years ago | (#13540606)

Or maybe it does.

http://en.wikipedia.org/wiki/Einstein_Refrigerator [wikipedia.org]

No moving parts.

Uses amonia, butane, and water...

Electricity "Not An Option?" (1)

Lagged2Death (31596) | more than 9 years ago | (#13540607)

This method requires a lot of compressed air, and ultimately, a lot of energy. If electricity "is not an option," (presumeably because of remoteness from a reliable grid) then where is the energy to make the compressed air coming from?

Because it would be far more efficient to just hook the energy source right up to a conventional refrigeration compressor, surely.

All in all, it sounds to me like the Sun Frost [sunfrost.com] people have a better plan, as far as sunny places go, at least.

Alternative uses...Uranium enrichment (2, Insightful)

grossinm (579783) | more than 9 years ago | (#13540621)

Is it just me, or does the fact that an alternative use for this process is the enrichment of uranium seem like a bad idea for the third world (read terrorist training ground)?

Where does the power come from? (1)

Jason1729 (561790) | more than 9 years ago | (#13540624)

Clearly this still takes power, even if it's coming from a user turning a crank.

It is an inefficient system, so why not use the same power source for something more efficient like a peltier junction?

How inefficient? (2, Insightful)

oddRaisin (139439) | more than 9 years ago | (#13540625)

How inefficient is horribly inefficient? The gas motors that powers all our vehicles is only 30% efficient, but that's when it's at its peak output (pedal to the metal). Most of the time it averages 17% efficient (17% of the energy generated actually makes it to the wheels).

For crying out loud... (1)

frgough (890240) | more than 9 years ago | (#13540659)

Just use one of these [lpappliances.com] .

Sheesh.

You guys are thinking way too hard (1)

doctorjay (860762) | more than 9 years ago | (#13540661)

just fill up a ice tray and leave it out side in sub zero temperature ... ice without elecricity :)

Why not use electricity? (4, Insightful)

HPNpilot (735362) | more than 9 years ago | (#13540670)

Couldn't read the full article as it is now "premium content" but if you can make compressed air you can make electricity, and use that electricity for more than refrigeration. The comments about the vortex tubes' inefficiency are correct, so even if you figure the inefficiencies of (solar/labor/water power) to electric then operation of either a freon or Peltier cooler, you are better off.


If someone wants to do something really interesting for the third world, make an adsorbtion freezer using solar concentrators for the heat source. This article discusses some issues: http://me.sjtu.edu.cn/english/scientific_research/ tpad.htm [sjtu.edu.cn]

The Mosquito Coast (0, Redundant)

Vellmont (569020) | more than 9 years ago | (#13540689)

And I thought this was just a movie. Harrison Ford starred in a movie [imdb.com] where a genius inventor makes exactly such a device that makes ice without electricity. Suffice it to say things didn't go to well for his character.

Full article (2, Informative)

nstrom (152310) | more than 9 years ago | (#13540691)

The full article seems to be available in the print-only version here:
http://www.time.com/time/magazine/printout/0,8816, 1101299,00.html [time.com]

You're not missing much, though -- I'm guessing this one was a sidebar blurb, as it's only two paragraphs anyways.

Reinventing the wheel? (4, Informative)

chill (34294) | more than 9 years ago | (#13540715)

The Romans used to make ice in the deserts of Palestine and North Africa. It seems to me they were around before electricity and Frigidaire.

http://www.madsci.org/posts/archives/nov99/9417235 40.Sh.r.html [madsci.org]

Of course, the large temperature difference between the day and night in the desert it what drives it. That method probably won't work in tropical climates.

  -Charles

Useful (1)

isorox (205688) | more than 9 years ago | (#13540716)

Perhaps they could do with this in LA [foxnews.com]

Article text (2, Informative)

Anonymous Coward | more than 9 years ago | (#13540731)

When he isn't snowboarding or volunteering for Engineers Without Borders, Dave Williams spends his days thinking about something most of us take for granted: ice. As he discovered on a volunteer trip to Haiti in 2002, ice can be a godsend to a poor village, keeping fish fresh on a journey to market or preserving vaccines. But how do you make it without electricity, without access to coolants like Freon or fuels like propane? Williams, 26, knew that forcing compressed air through a hole in the middle of a pipe causes hot and cold air to flow from opposite ends, a phenomenon known as the Ranque-Hilsch vortex-tube effect. No one is quite sure how the separation works, but feed the cold air into a container, he reasoned, and you would have an icemaker and a freezer, which would have zero operating costs and would be environmentally friendly, since it wouldn't require chemicals and the jet of air could be generated via a compressor powered by wind, water, man or animal.

At least that was the idea. Tinkering with heat-transfer equations, Williams tried to determine how much energy it would take to yield a block of ice. "It had been a while since I'd done real math problems. I had to break out the old textbook," says Williams, a product-development consultant with his own firm, Dissigno, in San Francisco. After eons of number crunching, he hit on the right formula and built a prototype. It isn't very efficient; his device uses 35 times as much energy as an electric fridge to make 1 kg of ice. But its simplicity could yield a killer app in Third World villages, where Williams hopes aid groups will distribute his icemaker as an economic-development tool. He aims to field-test it in Haiti later this year. --By Daren Fonda. Reported by Matt Smith/New York

picture (1)

dwight0 (513303) | more than 9 years ago | (#13540738)

here is a picture of one. it makes it easier to see how it works.

Where would the compressed air come from? (1)

nuggz (69912) | more than 9 years ago | (#13540747)

Where would you get the compressed air?
This doesn't work with wind.
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