$5 solar oven wins $75000 green innovation award

[archer]

http://www.ft.com/cms/s/0/966a21fa-13ae-11de-9e32-0000779fd2ac.html?nclick_check=1.

Solar-powered cardboard cooker
Kyoto Energy Ltd., Kenya
Published: March 18 2009 11:55 | Last updated: March 18 2009 11:55
Kyoto Box is a cheap, solar-powered cardboard cooker for use in rural Africa, estimated to prevent two tonnes of carbon dioxide emissions per family per year.

The $5 cooker uses the greenhouse effect to boil and bake. It consists of two cardboard boxes, one inside the other, with an acrylic cover that lets the sun’s power in and stops it escaping and doubles as a ‘hob top’. A layer of straw or newspaper between the boxes provides insulation, while black paint on the interior and the foil on the exterior concentrate the heat still further.

The design is so simple that the Kyoto Box can be produced in existing cardboard factories. It has just gone into production in a Nairobi factory that can produce 2.5 million boxes a month. A more durable model is being made from recycled plastic.

This fuel-less stove aims to address health problems in rural villages as well as avoiding carbon dioxide emissions: it provides a source of clean boiled water, cuts down on indoor smoke inhalation and reduces the need to gather firewood.

“This is the simplest idea I could find,” says Jon Bøhmer, inventor of Kyoto Box. “That is the philosophy behind it.” The Norwegian had already spent five years developing a more high-tech solar concentrator, but explains: “I wanted people to look more closely at this very straightforward solution which was ‘discovered’ 240 years ago.”

Mr Bøhmer envisions a network of women distributing thousands of the flat-pack devices from the backs of lorries to families across Africa and the developing world.

His hope is that the cooker will be eligible for carbon credits – hence the name Kyoto Box. The €20-30 yearly profit per stove would be passed on to the users, meaning the device pays for itself.

“It’s all about scaling it up,” sums up Mr Bøhmer. “There’s no point in creating something that can only help a few million people. The needs are universal – everybody needs to cook.”

[BigDanInTX]

I got the lengthier text from Financial Times, which requires you to register, blah blah blah...
http://www.ft.com/cms/s/966a21fa-13ae-11de-9e32-0000779fd2ac


Kyoto Energy Ltd., Kenya

Published: March 18 2009 11:55 | Last updated: March 18 2009 11:55

Kyoto Box is a cheap, solar-powered cardboard cooker for use in rural Africa, estimated to prevent two tonnes of carbon dioxide emissions per family per year.

The $5 cooker uses the greenhouse effect to boil and bake. It consists of two cardboard boxes, one inside the other, with an acrylic cover that lets the sun’s power in and stops it escaping and doubles as a ‘hob top’. A layer of straw or newspaper between the boxes provides insulation, while black paint on the interior and the foil on the exterior concentrate the heat still further.

The design is so simple that the Kyoto Box can be produced in existing cardboard factories. It has just gone into production in a Nairobi factory that can produce 2.5 million boxes a month. A more durable model is being made from recycled plastic.

This fuel-less stove aims to address health problems in rural villages as well as avoiding carbon dioxide emissions: it provides a source of clean boiled water, cuts down on indoor smoke inhalation and reduces the need to gather firewood.

Sir Terry Leahy
“As well as reducing carbon emissions and deforestation, this cheap and simple idea could save people in developing countries time and money”
“This is the simplest idea I could find,” says Jon Bøhmer, inventor of Kyoto Box. “That is the philosophy behind it.” The Norwegian had already spent five years developing a more high-tech solar concentrator, but explains: “I wanted people to look more closely at this very straightforward solution which was ‘discovered’ 240 years ago.”

Mr Bøhmer envisions a network of women distributing thousands of the flat-pack devices from the backs of lorries to families across Africa and the developing world.

His hope is that the cooker will be eligible for carbon credits – hence the name Kyoto Box. The €20-30 yearly profit per stove would be passed on to the users, meaning the device pays for itself.

“It’s all about scaling it up,” sums up Mr Bøhmer. “There’s no point in creating something that can only help a few million people. The needs are universal – everybody needs to cook.”

The author is Hannah Bullock, managing director of Green Futures

[archer]

Merged

[Roswell]

hmmmm.  I am trying to think how best to reverse engineer that.  It looks like the outer box has been lined with newspaper for insulation, the flaps are silver foil tape ( alluminum foil would work just as well).  the box inside is kind of hard for me to figure out from the picture though.  I can tell the top flaps are cut off and it fits snugly inside the other box.  the inside box has the sides lined with that same foil after that I am a little lost.  I can't see what the bottom of the inside box is lined with.   i guess that is a pot with a silver plate inside it all.  where does the acrylic top come in?  is that like a clear syran wrapping over the top?  If so, I guess I would cut the bottom out of the inner box so it will easily come on and off. Does this make sense?

[archer]

hmmmm.  I am trying to think how best to reverse engineer that.  It looks like the outer box has been lined with newspaper for insulation, the flaps are silver foil tape ( alluminum foil would work just as well).  the box inside is kind of hard for me to figure out from the picture though.  I can tell the top flaps are cut off and it fits snugly inside the other box.  the inside box has the sides lined with that same foil after that I am a little lost.  I can't see what the bottom of the inside box is lined with.   i guess that is a pot with a silver plate inside it all.  where does the acrylic top come in?  is that like a clear syran wrapping over the top?  If so, I guess I would cut the bottom out of the inner box so it will easily come on and off. Does this make sense?

You are close to what I see.
What I plan to do:
-paint outer box black
-put foil on the outer box lids and work out some support to keep them at a good angle
-put newspaper or something between the outer and inner box
-paint inside and outside of inner box black
-i have a sheet of plexiglass i picked up off of freecycle i'll cut a piece for so that it covers the inside of the outer box

[anthonyalston]

I read about this online and decided to give it a try.

It worked great. I was able to maintain 200 degrees F all day long. I used it like a crockpot and it worked well. I am looking forward to creating an entire meal using the solar oven. The most expensive part of the solar oven for me was the 18x20 inch piece of Plexiglas that I used for the top. I was very  impressed by the design. I used a 2x4 under the box to angle the oven to the sun.

I am now looking for ways to improve the solar oven for higher temperatures and heat retention. But, I do have to say for my first attempt at a solar oven, the design worked well and I was able to successfully cook food.

Being able to create this oven can be a really useful skill in times where fuel is short or when I just don't want to heat up the house or where camp fires are prohibited.

[Angie]

Wonder if anyone has build a home made solar oven using something more permanent than cardboard. I wondered if old microwave ovens would work?  I'm not knowledgeable enough to weld a metal box, but I'd like something that will last.  The steam and heat from cooking deteriorate the cardboard.  My primary purpose would be to save it for a SHTF situation.  Eventually cardboard will wear out.

I know you can order one from a charity that uses its profits to finance supplying these oven in 3 world countries.  It would be nice however, not to have to spend several hundred dollars.

Any suggestions for using something recycled buy long lasting?

[A Pawn]

You are close to what I see.
What I plan to do:
-paint outer box black
-put foil on the outer box lids and work out some support to keep them at a good angle
-put newspaper or something between the outer and inner box
-paint inside and outside of inner box black
-i have a sheet of plexiglass i picked up off of freecycle i'll cut a piece for so that it covers the inside of the outer box

Archer...you might want to rethink the plexiglass. I know that the solar oven is a low heat type cooker, but plexiglass only has a "continuous service temperature" of 180-200 degrees F so you might want to be aware of that....Above that it will soften and lose its shape.

Plexiglass may be great for a solar dehydrator though and is very good for a cold and hot boxs for starting plants and such... 

[Pathfinder]

This just in from CNN . . . .

The House of Representatives has just introduced a bill that would levy a special consumption tax on cardboard boxes used as solar ovens. The new tax i, if passed, will take effect immediately . . .





Just joking - for now.     

[Jimbo]

 Could you use sheet metal or flattened aluminum cans instead of foil if you're the sort who leans towards longevity?? 

[genocidal stain]

My son did this for Boy Scouts (with a lot of nagging from me) and we were able to reach 220 F by 10:30 am. Thats as high as the oven thermometer went. Next we'll try baking some bread perhaps.

[johnnyb_good30]

look u have to  check out this link it is badd   lots of ovens  http://www.solarcooking.org/plans/

[SLOHomemaker]

Maybe I can use DF's empty beer cans for the reflectors?

A tin snipper and some duct tape?

Piece of glass from Home Depot, some bricks, maybe more empty beer cans flattened out?