Making solar cookers in Kinshasa

I was living in Kinshasa, Democratic Republic of Congo, when I first heard of solar cookers. At first, my mother and I were incredulous that all you needed to cook food and pasteurize water was a simple device made of cardboard, aluminum foil, and a heat-resistant plastic bag, on top of a regular black pot. The vast majority of people in Kinshasa rely almost entirely on charcoal to cook their food, which has resulted in severely degraded forests within a 200 km-radius ring around the city(1). The problem grows worse every year. And it is certainly not limited to Kinshasa. According to the World Health Organization, half of the world’s population uses firewood to cook (2). With charcoal and firewood being so hard to get, so dirty to burn, and so destructive for the environment, solar cookers seemed too good to be true. How could something so cheap and simple not be widespread already?

We had to see it for ourselves, so we ordered a “Cookit” from Solar Cookers International. We tried something simple first, white rice. Even though we had read it would work, it was still a shock when we opened the lid and saw a steaming pot of fully cooked rice, with no apparent source of heat – no flames under the pot, no hot oven. It was hard to believe, but it was just good old sunlight that had done the job.

We then tried out different recipes. Vegetables, beans, meats, it could do it all. Everyone noticed that the food was tastier than usual, as slow-cooking preserves more of the food’s nutrition than regular cooking. In many ways, it was also easier to cook this way, because we didn’t have to watch the pot. We could just set it out and pretty much forget about it. A timer set for 30 minutes would remind us to go nudge it slightly so it would face the sun again. If we did forget it though, no problem! The worse that could happen is that the sun would move and the cooking would slow down. This was a big bonus point for me, as I was known for being absent-minded and leaving food on the stove or in the oven to burn. It was impossible to burn food in the solar cooker, as temperatures never got high enough. So you could reduce the amount of oil or butter and water, and the pot was always easy to clean.

These cooking experiments convinced us that indeed, solar cookers really do work, and quite well at that. The next step was to make one ourselves. We printed out the online instructions, and set to work. The hardest part was getting the measures right for a full-size template from the one-page image on the computer screen. My mother made her own image with instructions on how to do this, called the “Happy Planet Cookit,” which I can send to anyone interested. It took my mother and me about two hours to make one Cookit panel, including cutting out the cardboard pieces, taping them together, gluing on the aluminum foil and cutting the extra off, and making the desired folds and cuts. See these links for pictures of making the solar cookit panels: https://picasaweb.google.com/108485528695279638079/SophieSStories# and a video of me, my mother and sister cooking a vegetable mix in the Cookit: http://www.youtube.com/watch?v=sYc1gms0ru8&list=UUWGPGJGy3gox06Isu9MBLNQ&index=3&feature=plcp

We made sure our homemade Cookit panel worked just as well as the one we had ordered by using it to solar cook more food. Finally, we wanted to show this technology to people who might really benefit from it, in the hopes that they would like the idea and be motivated to build their own Cookits. We built two more Cookit panels, and decided to search for the other components in Kinshasa, to see how easy it would be for locals to make their own complete Cookit. Not surprisingly, we couldn’t find any turkey oven bags – in fact I think it’s hard to find turkey oven bags anywhere outside America, as other cultures don’t celebrate Thanksgiving, and find other ways to cook turkey if they do at all. Although there are other ways to get around the problem of heat retention through a plastic heat-resistant bag (glass bowls, for example), we figured we would just use our turkey oven bags for the time being and order some more bags from the US if needed. At 50 cents apiece from SCI, these were affordable to most locals. Although there is no functional postal service in Kinshasa, non-governmental organizations usually had some way of obtaining needed items from abroad – often just by asking a friend to buy it on their next trip home and bring it back in their suitcase. Plastic bags hardly take up any room. Next came the pot issue. Finding a black pot that was more or less airtight and not too thick was a very hard task. We could not find the right kind of pot no matter where we looked - on the streets, in open-air markets, and even in the expensive stores meant for the few rich and/or privileged Kinshasa dwellers (incuding Embassy and UN workers). Cheap pots abounded, but they were all shiny aluminum, and were of such poor quality that their lids barely fit on them, as both the lid and pot were so easily deformed. We considered painting some of these black, but did not know where to get non-toxic paint (there are ways to make your own, which we later found out). Ironically, the problem of finding black pots in the field wouldn’t really be a problem in most cases, because all these shiny aluminum pots soon become black from sitting over smoky charcoal fires. Finally, we settled for a greyish pot that was a bit too large for solar cooking, and decided to make the best of it.

References (indirect) (1) http://www.jembala.eu/Download/Jembala_Mampu_CatherinePaul_14102011.pdf (2) http://www.she-inc.org/