Engineers Aim To Make Cleaner-Burning Cookstoves For Developing World 147
vinces99 writes in with news about a new cookstove design for developing countries. "About 3 billion people, or 42 percent of the world's population, rely on burning materials such as wood, animal dung or coal in stoves for cooking and heating their homes. Often these stoves are crudely designed, and poor ventilation and damp wood can create a smoky, hazardous indoor environment day after day. A recent study in The Lancet estimates that 3.5 million people die each year as a result of indoor air pollution from open fires or rudimentary stoves in their homes. More than 900,000 people die from pneumonia alone, which has been linked to indoor air pollution. University of Washington engineers hope to make a dent in these numbers by designing a cookstove that meets a stringent set of emission and efficiency standards while still being affordable and attractive to families who cook over a flame each day. The team has received a $900,000 grant from the U.S. Department of Energy to design a better cookstove, which researchers say will use half as much fuel and cut emissions by 90 percent."
Poor ventilation... (Score:2)
From the concept art this looks like they are making a simple rocket stove and putting a pot skirt on top. There are quite a few people working to develop low cost, efficient, and nonpolluting cook stoves for poorer countries, but most of them use natural materials (stone, brick).
I'm just wondering how much one of these things would cost? Looking at the sleek concept art, I'm guessing more that a family living in a mud hut and cooking with twigs and cow dung can afford.
Not to mention that, if you're burning stuff, then poor ventilation in the vicinity of the stove will defeat much of the intent (health, clean-burning, etc.). This remains so, however well the stove may function in a better location.
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do tell, what "natural materials" are suitable for making a stove that don't require massive amounts of energy to modify for the purpose? If you are going to suggest a giant clay stove I'll laugh at you, they exist but only in places in no need of this article's stove, for an excellent reason.
Re:Will the cost be a barrier? (Score:4, Interesting)
I've made molten steel from scrap in a "giant clay stove". The clay was a chrome magnesite clay but it came out of the ground like that and the "stove" was an arc furnace, but there's plenty of stuff that can be found in a variety of places that can handle less extreme conditions.
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I've made molten steel from scrap in a "giant clay stove".
No you haven't, fire has never, never in the history of man, melted steel. I know this is true because I heard Rosie O'Donnell say so ;-)
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yes, and firing that clay is very energy intensive.
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Oh that's right - I forgot that you are the coder that goes around telling engineers that they know nothing about engineering. Do carry on in your own little bubble.
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you seem to have something missing between your ears. I'm an engineering physicist, and I do know about ceramics.
To make a stove with stack fire clay will indeed have to be kiln fired to be stabilized
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Since you never replied to my rebuff last year when you tried to inform me I knew nothing about engineering I assumed you didn't have that degree
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Adobe, rock, ash. Short pieces of rebar are cheap and readily accessible anywhere that cement structures are built. The Ministerio de Vivienda, the housing department, in Peru has implemented a program to construct 'improved stoves' throughout the country. The Ministerio will give people the chimney, fire grate (made of rebar) and instructions. The 'cocina mejorada' is many times more efficient than the open 'fogon' cook stove my brother-in-law used to use. A pot of water can be boiled with less than 1
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They would probably be better off building with cob
http://en.wikipedia.org/wiki/Cob_(building) [wikipedia.org]
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I initially assumed that the design would use natural materials - otherwise, what use could it be to anybody?
If it were my team, I'd be looking at ways to build it from natural materials first, found materials second, and using a minimum amount of manufactured materials. Found materials could be anything, from a length of pipe, to corrugated steel, an automobile muffler, a metal grate, or even brass AK-47 shell casings. They'd have to be ubiquitously common, and really cheap or free to obtain. They might even do some field work to learn what kinds of materials fit those qualifications in poor villages around the
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What do you consider "natural materials"? If you're limiting them to dirt, water, rocks, and plant material it's pretty difficult to get a good design, particularly since the plant material can't be used because it burns up. Still, as long as "dirt" isn't just sand, then water and dirt can be used to make brick, adobe, and with high enough temperatures free-form ceramics. They ought to be able to make a decent stove, complete with venting, with those materials, and the cost is labor and fuel to heat mud int
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Seems like they add a chimney around the fire so the updraught pulls air in at the bottom a la Dresden.
Things like this made of recycled materials (biscuit tins, bits of cars) were around 20 years ago.
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I think the barrier may be social and cultural. How people eat is very fundamental to their culture and hence how they cook. There are other designs for efficient stoves for the 3rd world out there but there does not seem to be much uptake. This may be more of a job for Anthropologists and Social Workers than Engineers.
We already hae better stoves (Score:1)
And fire places, people have been successfully using them for hundreds of years without killing themselves. Lets face it people, if your burning bullshit in a 50 gallon drum to cook your food "yet another better stove" isnt going to do you much good.
Re:We already hae better stoves (Score:5, Insightful)
Here's a picture of the new stove they are considering. [washington.edu]
The new one does look more efficient, but it looks like it costs 10 times more. Are people really going to buy it?
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nonsense, there are "traditional stoves" that look just like your 2nd picture. Designed by smart people who had a culture where they could pass good ideas along.
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Yeah that's not exactly hard. This entire thing is a waste of effort in terms of "making a better stove." Feel free to look up a daruma stove, or even the semi-classical pot-belly or mini-pot belly stove. The fun thing about pot belly stoves is they can be made from any material that doesn't burn. Of course the most common type was cast iron(iron of course being cheap during that time), but pure clay, and clay mixed with other materials such as asbestos was also common.
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I'll bet they don't levitate, like the ones in the 'picture'.
Now that's tech.
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nonsense, there are "traditional stoves" that look just like your 2nd picture. Designed by smart people who had a culture where they could pass good ideas along.
Wait. According to TFA, the first stove is an example of what the target audience is currently using, and the second is an artist's conception of what the new stove will look like. One of the design criteria is to look enough like the stoves they were used to that they would be mostly familiar with it's use, while being a significant improvement over what they were currently using. [1]
So, a Franklin stove (as others were suggesting) may not have as high adoption as something that looks like their current
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Here's a picture of the traditional stove. [washington.edu] Truly inefficient, you can see plenty of wasted energy leaving out the sides. ok.
Here's a picture of the new stove they are considering. [washington.edu]
The new one does look more efficient, but it looks like it costs 10 times more. Are people really going to buy it?
Ten times more? The first one looks free. Honestly this looks like yet another ivory tower project complete with a budget, interns, and computer aided engineering all to 'invent' something that has been around for ages.
This time it is the free-from-trash Hobo stove. [wikipedia.org] I'll research the idea for half price, only 450k. Hell, I'll even send the Department of Energy a few samples, just let me find my old coffee cans....
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Just because the rendering looks good doesn't mean that's what will end up in the developing world.
And at its most basic, that design can be stamped out, wholesale, from sheet metal.
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I think any design like this that relies on people *buying* it is ultimately going to fail. If you really wanted to improve these people's lives, you would design one that *they* can *make*.
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I think any design like this that relies on people *buying* it is ultimately going to fail.
I keep seeing people posting this kind of thing. Do you really think that people in developing countries have no money?
I can tell you a story. I knew a woman in El Salvador who was a cook, and she bought a pot that was big enough to make mondongo (cow stomach soup). She was really happy. Then somehow she lost it, and she was really sad. If she could have bought another one, she would have been really happy again.
So this sort of stove thing is the kind of thing people would buy if it were cheap enough,
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while millions of Americans live in poverty and can't get the help they need.
You don't know the meaning of poverty.
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And fire places, people have been successfully using them for hundreds of years without killing themselves.
It happened quite often.
Try thinking a little more carefully about the clothes women wore.
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> Try thinking a little more carefully about the clothes women wore.
When you are wearing a long dress near a fire, you can't help but try thinking a little more carefully.
Re:We already hae better stoves (Score:5, Informative)
Actually TLUD stoves would create char coal and burn the pyrolysis gases, now they are just wasted. The article is low on detail, here is a free ebook about stoves and their use in 3rd world countries:
http://www.biochar-international.org/sites/default/files/Understanding-Stoves-okt-10-webversion.pdf [biochar-in...tional.org]
and a slide show that explains the principle:
http://www.bme.gouv.ht/ugse/TCharbon%20Kara%20Grant%20-%20English.pdf [bme.gouv.ht]
I haven't seen this mentioned in the article which is somewhat thin on detail, but there is way more to stoves than the article explains. Also Burn Design Lab doesn't explicitly mention the TLUD design.
Oh, here is another website:
http://stoves.bioenergylists.org/ [bioenergylists.org]
Somehow the UW related stuff is free of the TLUD principle, I wonder why. Also, you are wrong.
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That patsari stove design looks simple enough to replicate, if you look at burn design lab you have to get the mass production of the steel stoves going first.
Making bricks may still be energy intensive, but somehow it feels easier to do. For simple energy starved societies this should still be easier to do than setting up steel processing.
(Just to mention it, Spanish isn't my strong side)
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Rocket Stove - not really revolutionary (Score:2, Interesting)
It's called rocket stove and can be built easily from different material:
http://en.wikipedia.org/wiki/Rocket_stove
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Even simpler. Use the fuel as the stove.
http://thechive.com/2012/01/11/a-finnish-stove-is-all-the-rage-inwell-finland-12-photos/ [thechive.com]
--
BMO
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Similar project (Score:3, Informative)
This reminds me of this project: Potential Energy (formerly The Darfur Stoves Project) [potentialenergy.org]
Popular Mechanics covered it in this article: Low-Tech Stove Saves Lives in Sudan's Darfur Region [popularmechanics.com]
Rocket stoves (Score:3)
Rocket stoves work pretty good. They burn at a higher temperature and consume more of the fuel while reducing emissions. Very easy to construct and cheap to fuel with just sticks and leaves.
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Rocket stoves (Score:3)
by CODiNE (27417)
Rocket stoves work pretty good.
That's probably better than my subject line. Mine was going to be "holy shit, assholes". Then the body was going to say "These already exist, and they are called rocket stoves." Possibly I might include an informative link [wikipedia.org].
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I'd mod you up if I had points to give. Rocket stoves and rocket mass heaters are the most promising developments in clean, high efficiency and low-cost heating.
Pressure cookers? (Score:1)
Running a woodstove is simple (Score:2)
Run it hot on clean, dry wood at full power for as long as you can, the thermal mass you surround it with will absorb the heat.
Oh wait, the reason folks burn crappy wet wood in inefficient stoves is that they're poor, or they're too sick from dirty water (50% of all premature deaths on Earth are from bad water) to gather wood. How does this help that problem?
So these guys, but 3 years late to the party? (Score:2)
So these guys, but 3 years late to the party?
http://www.cleancookstoves.org/ [cleancookstoves.org]
I guess mechanical and chemical engineering masters students all need a thesis subject...
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Or there's also the higher-tech approach taken by BioLite [biolitestove.com]. While obviously more expensive, that stove not only improves efficiency and health, but also provides electrical power generation capabilities suitable for charging smartphones and other low-energy electronic devices. Given how transformative cellphones are proving to be in developing economies, that's a non-trivial benefit.
Biolite anyone (Score:3)
http://www.biolitestove.com/homestove/overview/ [biolitestove.com] for the "homestove" which is intended for folks who need it "full time". Yes, it is more expensive, but they are working on funding sources.
One of the funding sources is us outdoor geeks, on their website you can find the campstove, the campgrill and the upcoming pot. Some of their profits go towards their homestove work.
I've got the campstove, it does a very nice job. Perhaps by next summer I'll invest in the grill.
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Reading some of the other citations (cooking stove treatise, etc.) it seems that lessons from the 5th century haven't propagated yet.
http://heritageofjapan.wordpress.com/following-the-trail-of-tumuli/rebellion-in-kyushu-and-the-rise-of-royal-estates/village-settlement-patterns-the-homestead-emerges/the-kamado-stove-innovation-improves-home-life/ [wordpress.com]
The key benefits of using "high" technology are cleaner burning and electricity generation for upfront investment (which presumably is being donated).
The southern ja
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I suppose the other clever (but non-electrical) approach would be to use a turbo charger. Pumping some of the exhaust gas back in and using it's thermal and kinetic energy to power the blower would do away with the need for a battery or external fan.
But when the basis against which solutions are compared against is three rocks under the cookpot it is hard to compete on the basis of simplicity.
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Biolite team has done extensive field test for their homestove, it really works (and rocks) for those people who do the daily cooking with wood stove.
And they use it to charge their cell phones and home light batteries, while saving on wood.
I use the summer camp smaller "geek" version of this stove, I'm happy with it even if it has some limitations the home version hasn't.
Silly (Score:2)
This design is nothing but a rocket stove which can be made from a variety of found components by someone with minimal tools and kn
Not to sound antiegalitarian... (Score:3)
...but isn't man's disruption of the natural processes that keep the population in check a direct contributor to the world overpopulation problem? From a strictly scientific point of view, drastically altering the mortality rate of the world's population by decreasing it (and increasing the birth/death ration) can't be a good thing. Many of these people have lived generations in their current environment, so why does a first world country believe they have the right to disrupt nature in such a drastic way?
So a first world country solves the woodstove problem, thereby decreasing mortality rates. Are they prepared to then step in and deal with inadequate water supplies, increases in loss of arable lands, higher rates of infant mortality, and other side effects of overpopulation?
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...but isn't man's disruption of the natural processes that keep the population in check a direct contributor to the world overpopulation problem?
No, On the contrary, population is increasing rapidly in Africa now, and is stable or dropping in all Western countries. Without exception, economic development has led to women's education which has led to near-replacement or below-replacement birthrates. Improving Africans' health will lead to a small temporary gain in population, and a much larger drop later on. The longer you wait for economic development, the larger the population and environmental impact will be later on.
Many of these people have lived generations in their current environment, so why does a first world country believe they have the right to disrupt nature in such a drastic way?
These people are not "nature".
Gasification? (Score:2)
My suggestion would be some form of multi-fuel gasification system. Its highly efficient and produces very low emissions. The problem would be simplifying its operation, making it smaller & engineering it so that it didn't require electricity (for the blower).
Another similar idea: Die Ofenmacher (Score:1)
research area for decades, solar anyone? (Score:3)
Bloody university PR departments presenting every research project as if it's some Eureka moment.
"For over a decade, cookstove experts and enthusiasts have gathered at Aprovecho [Research Center] [aprovecho.org]". In 2009 The New Yorker had a long article [newyorker.com] about stove enthusiasts designing better stoves, what's changed since then? The Chinese are already cranking out Rocket stoves in volume; other commenters have linked to www.cleancookstoves.org, Biolite, etc.. The problem isn't engineering, it's economics and cultural.
Meanwhile, any stove still requires spending hours collecting firewood, contributing to deforestation and CO2 emissions. As an adjunct people can put food in a black pot in an insulated container heated by a cheap solar reflector. But now you've got two $20 purchases per family, one of which only works part of the time. Meanwhile the U.N. spends millions trucking fuel into refugee camps. Again, the problems are NOT engineering ones.
Trivial to do (Score:2)
Can they afford them? (Score:1)
Are those significantly cheaper than the ones they had before?
Re:Simpsons already did it... (Score:5, Insightful)
Didnt Philips do this 5 to 10 years ago????/
Didn't Ben Franklin do this 250 years ago?
"The Franklin stove is a metal-lined fireplace named after its inventor, Benjamin Franklin. It was invented in 1741. It had a hollow baffle near the rear (to transfer more heat from the fire to a room's air) and relied on an "inverted siphon" to draw the fire's hot fumes around the baffle. It was intended to produce more heat and less smoke than an ordinary open fireplace."
http://en.wikipedia.org/wiki/Franklin_stove [wikipedia.org]
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Enclosed stove with a stack and convection-based oxygenating of fuel, been done for thousands of years in various places in asia and africa. I swear, I get tired of reading of "innovations" that seem to be rediscovered every decade of my 50 years, but this is even more annoying.
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See how stupid that looks? Now you've seen exactly how stupid your post looks to anyone that thinks about design.
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I'm with you on that. But this doesn't look all that efficient as a rocket stove.
Frankly, if youtube were consulted first, they'd have found better (and worse) designs.
What is wrong with building them gasifying stoves. Then they could cook a meal, run a generator, make creosote for preserving wood and make more fuel simultaneously. Wrap the pipe with copper tubing and heat water for a bath. How about thinking just a teensy bit outside the pat-yourself-on-the-back-for-helping box and address these peoples ne
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Then they could cook a meal, run a generator, make creosote for preserving wood and make more fuel simultaneously. Wrap the pipe with copper tubing and heat water for a bath.
I'm reminded of something I heard from a nutritionist years ago. They had a list of stages that a person is in with respect to nutrition with stage 1 being horrible nutrition with no interest in changing their ways and stage 7 being ideal, or something like that. Some of the stages were just mental like "finding out about nutrition" or "showing interest in change." Well it turns out the goal of the nutritionist isn't to take to a stage 1 person and shove him into stage 5 or 7. That fails almost every time.
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Yeah, let's just keep them cooking with shit in an unventilated room, after all they couldn't possibly upgrade their lives because they are so much stupider than you.
Hubris is; blowing a big public image up over helping someone and then not delivering any more than is easy to do, for the cameras, of course.
Can't beat that market-research either, gonna sell them some help. Nope, people are mostly ignorant sub-morons. Colleges are full of them, some tenured.
Youtube seems to be a much more efficient way of lea
Missing the point by fifty miles (Score:2)
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Re:Simpsons already did it... (Score:5, Interesting)
Enclosed stove with a stack and convection-based oxygenating of fuel, been done for thousands of years in various places in asia and africa.
The stove in the article looks exactly like the cookstoves we made from coffee cans when I was in the girl scouts*. They work well, and are a big improvement over an open fire, but I don't see anything new about it.
*Yes, I was a male girl scout. My mom was the scout leader, and my sisters were already girl scouts, so she signed me up too. My mom was a tough scout leader. Years later, I enlisted in the Marine Corps, and it was a piece of cake compared to my mom's girl scout troop. -- Semper Fi, and Be Prepared.
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They have a camping stove that is somewhat similar, but with the added advantage of having forced air.
It's basically a coffee-can sized container with a fan on the bottom to force air through the fuel. They usually run on rechargeable batteries, but they can also be powered by a solar cell (or the batteries can be recharged with a solar cell).
It seems to me that this would be a much better solution compared to inventing something completely new. If appropriately-sized containers can be found or fabri
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How did you feel at the time about being in the Girl Scouts?
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Irrelevant. The problem is that they can't afford any stove in the first place:
"A recent study published in The Lancet estimates that 3.5 million people die each year as a result of indoor air pollution from open fires or rudimentary stoves in their homes."
I guess the real 'news' is this:
"The team received a $900,000 grant"
Loving this line as well: "[...] a better cookstove, which researchers say will use half as much fuel and cut emissions by 90 percent."
Compared to what? Open fire? Congratu-fucking-lation
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The problem is that they can't afford any stove in the first place
Apparently they can afford rudimentary stoves, which, according to the English language, are types of stoves.
So if this money can be used to create the infrastructure necessary to produce better stoves at a cost comparable to a rudimentary stove, then the lives of many people can be improved for relatively little cost. I am not saying that this is definitely going to work. The devil is in the details. But I don't think it's a bad idea per se.
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from the picture it can't ever be comparable to rudimentary stove in cost...
you could always make two crappy stoves from the materials that go into it.. sure, you would need to gather double the wood to cook with them but still..
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What you're saying is an attractive excuse because it puts the blame on poverty rather than the people themselves, but does it make sense? There are some investments that require money, some that require time, or both. The ones that require a time investment and yield a time savings can be done almost immediately. I don't think there are many communities on the planet where every person works at maximum capacity ALL the time. It's certainly not happening in the entire developing world simultaneously. Someon
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What you're saying is an attractive excuse because it puts the blame on poverty rather than the people themselves, but does it make sense?
What I said was that poverty is the cause of poverty. Being poor in the first place is the cause of staying poor. I wasn't blaming anybody for anything. I was suggesting that this cycle of poverty can be easily broken by people not stuck within the cycle.
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I was suggesting that this cycle of poverty can be easily broken by people not stuck within the cycle.
Looking at people on welfare in the US, it seems like it's not very easy to break the cycle even when you're giving people tens of thousands a year in cash, food, housing, and public education. Some people get off welfare, others are on for much of their lives just like their parents before them.
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Poverty is one of thse problems that can be solved by throwing money at it.
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A big chunk of people on welfare in the US are completely dependent on it. Which means that without welfare, there would be no reason for them not to be as poor as the poorest people in Africa.
How would you explain the fact that the quality of life for people on welfare in the US is so much higher than people in Africa. People on welfare in the US have access to safe food, clean water, healthcare, mobile phones, television, etc, if not for the welfare system we have in place?
The quality of life in the US
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Apparently they can afford rudimentary stoves, which, according to the English language, are types of stoves.
Rudimentary implies that they're very very probably not store-bought stoves ("Hello, good sir. I'd like one of you finest rudimentary stoves."), but rather bits and pieces thrown together.
You should take a look at TFA, especially at the picture with the following caption: "A crude cookstove over an open-flame fire."
Personally, I think 'makeshift' would have been a better description than 'crude' or 'rudimentary'.
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I did read the article and I saw the picture. "Cost" means more than just cost in money to build a stove. There is the cost in human time and effort in making your own rudimentary stove and operating it.
According to TFA "3.5 million people die each year as a result of indoor air pollution from open fires or rudimentary stoves in their homes. More than 900,000 people die from pneumonia alone, which has been linked to indoor air pollution."
Surely a person could be far more productive if they don't contrac
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Even if the stove costs like $10 (which is a lot for people in 3rd world countries), this is a smaller long term cost than being sick and dying earlier.
Somehow, I think that if you have to cook your food in your single pan over an open fire, long term concerns aren't really high on the list.
I do agree that it is a good investment, though. But I think that holds for stoves currently available as well. It seems getting corrupt governments to invest in them and honestly distribute them is the real problem.
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Somehow, I think that if you have to cook your food in your single pan over an open fire, long term concerns aren't really high on the list.
No they aren't, which is why it is important to reduce the cost as much as possible. People barely scraping by don't have the luxury of making long term investments like education. They need to spend their time on what they know works and will keep them alive. Unfortunately what they know works is really inefficient. But if costs can be brought down low enough, then they don't need to make a long term investment. They can make a low or medium term investment with the same benefit potential.
And it may be
Patents (Score:3)
In 1742, Franklin finished his first design which implemented new scientific concepts about heat which had been developed by the Dutch physician Herman Boerhaave (1668–1738), a proponent of Isaac Newton's ideas. Two years later, Franklin wrote a pamphlet describing his design and how it operated in order to sell his product. Around this time, the deputy governor of Pennsylvania, George Thomas, made an offer to Franklin to patent his design, but Franklin never patented any of his designs and inventions. He believed “that as we enjoy great advantages from the inventions of others, we should be glad of an opportunity to serve others by any invention of ours, and this we should do freely and generously”.
Wow.
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Who owns the patent now?
Nobody, that's the whole point.
Re:Russians already did it... (Score:2)
>> Didnt Philips do this 5 to 10 years ago????/
> Didn't Ben Franklin do this 250 years ago?
Didn't the russians do this over 1000 years ago?
The russian oven [wikipedia.org] is considerably more efficient than Franklin's. Designed to retain heat for a very long time, it contains an intricate brick maze of passages and chambers. Russians have used this type of oven since ancient times, cooking, baking, bathing (inside), sleeping (on top), hiding, and healing. The oven is prominently featured in many old stories and l
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I personally own a small Russian oven (I am Russian) and am repairing it just now so I must stress that it's NOT so efficient. Problem is that to collect all the smoke produced in a furnace the passages should be short enough limiting the heat collection efficiency. So the two-furnace ovens are usually built but it differs from a traditional design. The second furnace has a traditional "Holland" construction.
And a traditional Russian oven is too big. There should be at least 1.5*2 meters sleeping place on t
And so have others (Score:2)
Here's yet another one:
http://www.brownongreen.net/2011/05/simple-stove-improves-human-health-environment.html [brownongreen.net]
I think:
1) The wheel is being reinvented due to lack of communications
and
2) The problem may not be technological but Social and Cultural. Changing the way people cook may be a very hard.
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I am of the opinion that you are not posing your question in good faith.
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Yup eygypt isn't in africa at all. And they definiately didn't have chariots. No ser-ie
Ignorant fuck
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