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Inventor of Low Tech Fridge Wins Award
juju2112 writes "Mohammed Bah Abba of Nigeria won a Rolex award for his pot-in-pot invention. Here's how it works. You take a smaller pot and put it inside a larger pot. Fill the space in between them with wet sand, and cover the top with a wet cloth. When the water evaporates, it pulls the heat out with it, making the inside cold. It's a natural, cheap, easy-to-make refrigerator."
Grab a clean sock, soak in water, wring out, cover teh can of beer and leave on the window sill.. LOL
i'd sure like to know how often you have to change the wet sand, in order to get 2 weeks worth of refrigeration?
...
anyone got any napkin-science calculations that can give us a ballpark of whats needed? i'm sure this is a simple physics equation, only i'm certainly not qualified to work out the formula
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
This same man (and invention) won an invention of the year award from time (as seen here) in 2001. I guess it's interesting that he also won this award, but why is Rolex handing out awards years after the fact? Maybe I'm just used to the break neck pace of computer advancement, but this seems a little.. late.
Does it make much difference what the materials of the pot are? I know they used clay pots, but do they need to be glazed, unglazed etc? Would plastic pots work (it's not just the 3rd would that has a use for battery free fridges).
I was thinking that perhaps it might work best if the external pot was slightly porus, to aid evaporation, but perhaps all the evaporation occurs at the top, so it doesn't make much difference.
When I used to leave for work at 6am and the milk arrived at 6:30am, I had "milk cooler" which was like a tall flower pot. I left it by the front door, soaking in a bucket full of water. The milkman would pop it over the bottle he delivered each morning. Neither of us got a Rolex for it, though. Maybe people who make Rolexes don't know about the bleedin' obvious. (And while we're at it, we could wonder who makes their watch movements and, indeed, watch bands. Doesn't leave Rolex with much to do.)
Using water to avoid food freezing used to be very common in Norway (and doubtless in other countries with similar climates) before the advent of electricity.
Put a few buckets of water in your food storage room, and as long as the water is not frozen, the food in the room will not freeze either. Just before the water freezes, replace the buckets with liquid water. Repeat as necessary, and the food will not freeze.
Prior art apart, this is more a case of practical application on a scale previously unknown for this device.
The main reason for any award that this "device" would be eligible for is of course its social impact. If a simple arrangement of clay pots can prolong the life of perishable food in areas that don't have our "off the shelf from the supermarket perceptual abundance", it's got my vote. If it can drive more kids to school rather than have them vending out on the streets, it should have your vote too.
You might be well right when you say that this is an old invention. But I would caution against demeriting it simpy on account of that. Once again, clearly, the impact of the invention's application counts just as much as (maybe even more than) the invention itself.
One more example of applied commonplace knowledge -- Freeplay radio. Just how long have we known of windup springs and their potential energy???
Thousands of years ago potters allready knew how to make pots sufficiently pourous that they would keep the water cool by sweating.
And if you thought that was boring you obviously havn't read my Journal ;-)
I second the people posting that its around 4000 year old method.
I'm from India and I first I read about it when I was around 10 year old (I'm 23) in a popular social magazine (called 'Dharmyuga', the most popular magazine of its time). It had schematics identical to those offered by this fellow, and yes, they mentioned it to be "very old technique". My dad still has collection of old issues of this mag and I'm sure I can fish out the article mentioning this 'invention'.
Can't these fellows do at least a google query to verify that whatever they're offering money for is indeed an invention ??
Several docs with feedback
- mritunjai
If this is so blindingly obvious maybe you should have invented it and started selling low-cost refridgeration equipment in Africa. If you read up on the effects of this device you would find that young women in families that use the device are now allowed to go to school instead of being sent to the market to sell goods? Why? Because crops last longer so they don't have to sell them as soon as they pick them.
So tell those young girls that it doesn't matter. Tell the same thing to families that have food that lasts weeks instead of days.
Just because something is simple doesn't mean it doesn't matter.
Lasers Controlled Games!
I love posts like these:
/not one of you/ came up with it. It's a paperclip/washingpeg like idea.
"It's a more or less obvious solution for anyone who knows some rudimentary thermodynamics"
Very cute: but I'll tell you that stuff like this isn't even totally obvious for people who know quite advanced thermodynamics. Sure, it helps to know some laws, some integration/differentation techniques. But to actually apply it in such a simple and effective way is a whole different kettle of fish entirely.
An idea isn't worth much without application of that idea. And I'd wager that you (and many of the 'oh, this is basic'-posting crowd) people wouldn't have thought this up even with a thermodynamics textbook up their arse. I know I didn't. This idea is only self-evident when you're told about it's solution, and the proof is that, knowing the problems people in africa have with their lack of refregiration,
And previous invention of the basic idea (as mentioned in some other posts) doesn't detract from the accomplishment; especiallly if theh guy never heard of those.
And by the way, isn't magnetic cooling quite a new concept in refrigeration? And what about lasercooling (even though that's obviously not scalable to the macro-environment)?
-- Waht? Tehr's a preveiw buottn?
Grats to this guy for winning the recognition. But from what I understand in his culture the money he receives will just have to be doled out to his family, and his extended family, and their families, etc.
Someone correct me if I'm wrong here, but that's part of the problem with entreprenuership in a lot of African nations. As soon as you start to get somewhere, people start crawling out of the woodwork looking for handouts as part of your family, and it's against traditions to not give the assistance to them. That's why nepotism is such a problem. If you are elected to a position of power you pretty much have to hire your relatives.
I'm assuming this based on the following story: I dated a (great) woman for about two years who lived in Rwanda for 18 months. While there for the state department, she taught a native how to manage his small furniture business and turn a respectable profit. Once he started making enough gains to expand and have a chance at doing more than just surviving off his work (expand his shop, hire more carpenters, open a real store, etc.) she learned that his family threw some serious pressure at him to buck her advice and give the money to them.
So he never was able to make a business to sustain his family because they didn't understand he needed to pay people working for him to bring even more in. Don't spend the seed money.
You are checking your backups, aren't you?
We used to take a hand's width "slice" of straw from the end of a square bale, make it wet and stick in the window - instant air conditioner. The breeze blowing through it (coming INTO the room - you don't want to cool the OUTSIDE) had the heat "removed" with this same process.
I doubt those people have the straw/grass/etc. to waste on A/C, though.
I think they are refering to producers of the fruit, if all the sellers have fruit that lasts for a week and the buyers are the only ones with refridgeration, sellers will sell at lower prices to get the fruit off their hands before it spoils, this gives sellers signficantly more negotiating leverage.
Degaussing scares the bad magnetism out of the monitor and fills it with good karma.
In the American West, these are common. We call them Swamp Coolers. We have moist pads on 4 sides and exhaust throught the bottom, usually.
--- "1.21 Jigawatts!" -Doc
So how cold can these things make their interiors? The article mentioned being able to keep perishables for three weeks, which seems to be on par with my fridge -- if not better! But what does that translate to in degrees Fahrenheit (or, for the rest of the world, Celsius) with, say, a dry 100-degree F ambient?
Cal me when you can freeze water in that device... Until then I'll stick to my solar fridge that cost $395.00
Let's see, in my calculations $395 is a bit more than this device.
Also, the next time your in the third-world areas, see how many people can afford a $395 solar fridge. This is obviously not geared towards you.
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Er, isn't the whole problem with deserts the LACK of water?
A gadget like this will consume a fair bit of water, surely? More in hot, dry weather.
As a matter of interest, my Scottish grandmother used something similar, a pan of water with a [non-porous] milk container, wet cloth on top. The non-porous pan meant the water only evaporated through the cloth, thus slowing water consumption.
Here in Australia, we use canvas water bags hung outside the car - they stay cool all right, especially as you drive along. (Disclaimer, don't try this in a city)
"Cats like plain crisps"
Most of us at least have a fridge freezer...yes? If you don't then personal cooling is probably the least of your problems.
;)
I lived in North Queensland Australia, where its fairly hot and very humid so evaporative cooling is pretty much useless. We used to freeze icecream buckets of water in the freezer, smash them up and put them in a big metal tray. Take the tray into the room to be cooled and blow a little pedestal fan over it. It cools you for long enough to get to sleep at least. Doubles as an infuriating spray of icy water on your crotch when you step on it going to the can at 3am
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