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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."
I think it's great that prizes like this don't always go to fancy hi-tech stuff. Like the article sais, this invention can and have changed peoples lives.
Martin
Unfortunately such methods have been used in ancient Egypt 4000 years ago already.
Prior art anyone ?
nope - there is something like 4500 years of prior art on this one - bedouin tribes have been using this for ever. I saw this used 10 years ago on holiday in Egypt. So Rolex grabs the first Nigerian that has seen something cool while on holiday and actually implemented it at home, and gives him a friggin "award" for his "invention".
People who think they know everything are a great annoyance to those of us who do.
..but maybe the difference is in the execution or something? To me, it's less important that someone might have done this before than the fact that doing it now might change peoples life to the better.
Shouldn't that be the focus of inventing new ways for doing things by the way? To improve peoples life?
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
As long as you keep it in the shade I doubt you need to rewet the sand too often. Two layers of clay (or whatever the pots are made out of) as well as a few inches of sand should insulate fairly well. If anyone has a site that lists the "R" values (insulation coefficiants) of sand and clay all you'd need to do is compare that to something like a cooler (at least to get an idea on how effective this is).
Just like your refridgerator at home the main limitation\factor in terms of heat loss is going to be how often you open the fridge and whether you cover it with something more substantial than a cloth once the water is done evaporating.
Such a cooler would work with any pot material, just with different efficiencies.
;-)
Ideally, you want the outside pot to be a good thermal insulator and the inside pot to be a good thermal conductor. That way, the heat consumed by evaporation is drawn from the contents inside rather than the outside air. Maybe a copper pot inside some sort of oversize thermos with a porous cover would be ideal...of course, such materials probably aren't available cheaply where they're using these
Unglazed clay will work better due to water seeping through the pot and evaporating. It's very common to store drinking water in clay pots in India for exactly that reason (nowardays it'll be carried from the well in plastic pots)
In soviet russia stale jokes recycle you!
Thank god this only needs water, and they have an infinity supply of that in 3rd world countries, as we all well know.
The funny part is that the article you quote also quotes the Rolex award for the Nigerian man.
So we all know that evaperative cooling has been around for a while, but can anyone explain if this particular application has been used? This still looks novel to me.
TW
The clay is wet. The sand is wet. It all has the R value of a wet paper bag, which is to say that it's "anti" insulation.
That's the whole point. It doesn't retain cold, it creates cold. Put on a wet Tshirt on a chilly day and go outside. Get it? It works by heat loss, and thus that's what you're striving to accomplish. The exact opposite of the way you think of a cooler.
The whole thing works by continuous evaporation. It lasts longer in the shade, but it actually gets colder quicker if you dampen the outside and give it a bit of sun.
When the thing goes dry it has the R value of a dry paper bag, which is to say, essentially zilch. You have to keep it wet or the whole thing goes to hell, just like when that Tshirt dries out.
And as I explain in a post above the whole thing actually works better if you use an unglazed porous outside pot. Water seeps through the pot slowly, just fast enough so that the outside always feels a liiiiittle damp, but never wet, and you get the entire surface of the outside pot as cooling area. Throw a real lid on the thing instead of the damp cloth and it'll go for quite some time before you need to add water, although just how long "some time" is is highly variable, since it depends on factors like air temperature and humidity.
KFG
Dude, you think anything mentioned in India is ever going to get any credit? The rest of the world thinks that the Arabs invented Chess, and same goes for the decimal number system. No point explaining some things come from India, nobody will believe us.
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Yes. The thermodynamics involved in the device have been known for thousands of years. But the invenion is appling this to keeping food cool in a Nigerian village. To the best of mine, and Rolex's knowledge, nobody has apparently tried that particular feat before on a Nigerian village.
“Common sense is not so common.” — Voltaire
The whole thing works by continuous evaporation. It lasts longer in the shade, but it actually gets colder quicker if you dampen the outside and give it a bit of sun.
That's not true. If you put it in the sun, the water will evaporate faster and more energy will be transferred, that's true. But also more energy will be added to the system in the first place, and I doubt the higher evaporation will suffice to compensate for that. Even in the best case, it will exactly compensate, not overcompensate.
Other means for accelerating the evaporation can have a positive effect: cooling will go faster in dry air than in humid air, and also if there is circulation of air, as caused by placing it outside when it's windy or by placing a fan next to it.
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I was going to say, this thing has been in the Scout handbook forever.
i remember my dad and grandad used to tell me stories from WW2, when their house was burnt down by the Germans (in Greece), they used to bury in the ground ceramic pots to keep the olive oil and food cool and fresh. Not to mention ancient Greeks who did something similar back in 500 b.c. (thats why even nowadays archeologists find ceramic pots filled with wine and olive oil). This is a very old trick, and an effective one indeed, but why should a bloody Nigerian be awarded for something already done ages ago...Not to mention the similar and classic trick that you can produce water by evaporation (bury a ceramic pot in the ground, put a plastic cover, and in a full day there will be enough water in there, evaporated from the ground)...
Roses are red, violets are blue, most poems rhyme, but this one doesn't...
Definitely not new tech, but this is the first documented application with such social significance as freeing up kids to go to school. Kudos to the awards panel for recognizing his ingeniousness and benefits to other people
This is about how someone came up with an easily packaged low-tech device that will help millions of people. Sure, it's obvious, but he's doing something that will actually help people.
But presumably there is some engineering (how thick the pots, how wide the space, how fine the sand, how wet the sand) that was optimized to get the most efficient cooling.
That's what's worth detailing. Some of the variables probably don't matter. Some do. Figuring out what's important is true engineering, even if it doesn't involve lasers and five decimal places.
Is it new, no. But does that really matter?
Edison did not invent the lightbulb, he only perfected a lab curiousity so that it was feasable for everday use.
Ford did not invent the auto assembly line (Randsom E Olds did that) Ford improved upon it where he could mass produce cars and provide it to the masses at an affordable cost.
Did this guy invent something new? Probably not, but I think the people who will be using it will thank him for having it in their house.
Invetion is fine, but without application and distrubution, it is meaningless to most people.
"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"
You're being goofy.
Its not being "put down" because its old; hell the wheel is really old, and we seem to agree its a good idea.
No, the problem is that this is similar to someone patenting the obvious. People have known about it for thousands of years, they've used it. Now this guy wins an award because he what.... wrote a paper on it?
Cripes. Is the bar for "new and novel" so low these days that a guy got an award for discovering water evaporates and cools things?
Is that all it takes these days?
The real question is - how widely this invention is used today, 4 years after the award was given. It doesn't look like there are some huge barriers to entry in the business of pot-in-pot manufacture, it doesn't look like the technology is complicated, so what is the result?
Are Africans using this in droves to improve their living conditions? And if not, what does that mean? That they are stupid people who are not well suited to live in the modern world and thus do not deserve to survive? Or that we should send more humanitarian (development) aid to them? Not trolling, just honestly curious.
Future Wiki -- If you don't think about the future, you cannot have one.
I never ceases to amaze me how modern people assume "primitive" means stupid. And that would just be primitive by our standards of technology. Doesn't say anything about thier level of mathmatics or astronomy. There are plenty of amazing things done in history without the use of electricity or modern metals.
For instance the Romans would move water hundreds of miles without the use of any pumps. Only gravity would be used. There is once site in Spain where the Romans used water to tear down a mountain to mine it. Something we would use explosives and heavy machines to do.
I esp. love the nut jobs who assume that because the people of Egypt didn't have bulldozers and crains they couldn't have built the pyramids. Instead it was built by aliens or people from Atlantis. Which is all poppycock, the Egyptians had a prefectly "primitive" way of doing it, we just forgot what it was.
Primitive is relative, but it doesn't mean stupid.
Supporting World Peace Through Nuclear Pacification
Being original isn't the damn point. The award wasn't for innovation, it's an entrepreneurial award for building a company on this idea (and improving people's lives by selling a well-made implementation of the product, what capitalism is actually about - in other words, to put it bluntly, this is an "award for learning to be a good capitalist", probably an unusual concept in (white male) American capitalism, but probably comparable to e.g. 'businesswoman of the year' type awards that still reward female capitalist success stories in developed countries).
Check this link: it's called the "THE ROLEX AWARDS FOR ENTERPRISE". Quote, "He has already sold 12,000".