$6 Solar Cooker Wins $75K Climate Change Prize

by , 04/10/09

kyoto box, cardboard solar cooker, john bohmer, greenhouse effect technology, clean water, cooking water, lumber for heating, climate change challenge, global warming

Think humankind discovering fire was revolutionary? How about a cardboard box that uses the sun’s rays to cook without burning firewood? That’s precisely what the Kyoto Box, a cardboard solar cooker, can do. Made out of basic, 5th-grade-science-experiment type materials, the Kyoto box solar cooker offers a life-altering solution for thousands of people: the ability to cook and heat water without burning wood. So how does it work? Inventor John Bohmer says the box uses “the greenhouse effect for something good.”

The Kyoto Box consists of two cardboard boxes, one which Bohmer’s own 5-year-old daughter helped him paint black, and another covered with tin foil to help concentrate the sun’s rays. A plexiglass cover is used to trap heat inside making it possible for the box to boil and bake, but not fry, so it is arguable that it is healthy as well.  The Kyoto Box is already in production at a factory in Nairobi, and Bohmer hopes to offer a the box in a recycled plastic form in the future. The cost of the box will be a mere 5 euros.

kyoto box, cardboard solar cooker, john bohmer, greenhouse effect technology, clean water, cooking water, lumber for heating, climate change challenge, global warming

The idea for the Kyoto Box came from Kenyan-based inventor John Bohmer’s desire to create a cooking apparatus that would eliminate the need to burn lumber, which not only leads to deforestation but also emits harmful CO2. Judges of Forum for the Future’s Climate Change Challenge were certainly impressed by the ability of the box to alleviate global warming issues, but were even more keen on the what the Kyoto Box could mean to parts of the world where finding lumber to cook with and clean water to drink is an everyday struggle.

Photos courtesy of FastCompany.com and FT.com.

+ The Kyoto Box Solar Cooker

NOTE: Updates have revealed that the Kyoto Box is just one version of a solar cardboard cooker. Other examples can be found here and here, or through a google search.

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  1. Tara Howell December 8, 2012 at 3:41 pm

    Serious Bull Poop! We made these things all the time when I was in Girl Scouts THIRTY years ago!!!

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  3. wilchongsky August 5, 2009 at 3:21 am

    I read with interest your marvelous invention. I understand solar energy can be harnessed to create cooking heat up to over 160 degress celcius. I have been involved in helping my students build soalr oven for the past 3 years with materials quite similar to yours. However, we have yet to generate temperatures beyond 71 degrees celcius. We applied the “greenhouse effect as well as “Black Body Radiation” principles but to no avail. We would appreciate your advice. Thank you.

  4. lawrence agira May 2, 2009 at 5:20 am

    this is the time the world has needed solar heater most.its existence for more than a decade or a century could not catch the judges eyes for their were more alarming issues at the time hence congratulations to Bohmer and the judges for their timely invention.

  5. Yuka Yoneda April 13, 2009 at 9:33 am

    Mayhla, I completely agree with your bewilderment that this awesome invention is not unique. In fact, Bohmer even states in his interview that the practice of using the sun’s rays to cook has been around for 240 years!

    Although I’m not quite sure why it took such a long time for such a useful tool to gain the recognition it deserves, I think the important thing is that it finally did. The inventor is using the momentum to mass-produce and bring the kyoto box to the people who need it most.

  6. mayhla April 12, 2009 at 6:56 pm

    This exact thing has been around for over 10 years. In fact there is a organization that has used local people to make them and they are given away for free and they even fold up! I don\’t understand why this person is receiving a huge amount of money for something that has already been invented! Just put in SCI Solar Cooking International….or here is a link to a youtube video about solar cooking in Darfur! http://www.youtube.com/watch?v=Yz_a6sCP0Ww
    Here is another one that shows people actually making them! http://www.youtube.com/watch?v=r_aNGYrBGbI
    Now, tell me that this guy deserves this money?!?

  7. Carlo April 11, 2009 at 9:21 pm

    I think the main point here is the fact that it cleans up water (to a certain degree anyway). Actually I know it is, having read a short interview with the creator about a week ago.

  8. Yuka Yoneda April 11, 2009 at 5:02 pm

    Kudos to your son saltchunk. Is he into progressive design?

    I agree with you about the success of the product riding on whether or not locals will use it for making their favorites. I think it’s great that the cooker can make rice (which is a must for anywhere in Asia and many other parts of the world), but I do hope that Mr. Bohmer continues to study, adapt and even provide training programs for how to use the Kyoto Box.

  9. saltchunk April 10, 2009 at 9:11 am

    Funny, my son\’s fourth grade science experiment was a solar oven quite similar to this cooker. It is indeed very cheap to make and it worked fairly well even in relatively mild spring conditions in the mountains of east Tennessee.

    I think that the biggest challenge for solar ovens is figuring out how to adapt them to local cultural food practices. There are numerous advantages in solar ovens in terms of saving trees and in cutting down on indoor air pollution, for example. Also, these cookers allow hands free cooking thereby freeing up people to do other things with their time. However, if indigenous folks can\’t cook their traditional faves they are less likely to use these solar cookers. So, for this device to truly succeed, the designer should team up with anthropologists, local chefs and the like to figure out how to cook food which will satisfy local palate.

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