Sustainable futures
Clean cooking, kitchen culture and climate change
According to the Clean Cooking Alliance, cooking on open fires and on inefficient wood-burning stoves emits 25% of global black carbon emissions; the second largest contributor to climate change after carbon dioxide. Hence, clean cooking is vital to combat climate change and to reduce environmental degradation.
My research into sustainable, appropriate technologies includes the design of novel fuel-efficient wood-burning stoves and biogas cooking systems. But developing new cooking technologies is only one part of the solution.
I’ve worked on cooking stoves for about 20 years. In that time, I’ve heard many stories about cooking that have challenged my simplistic engineering approach to technology. Simply building a “better” stove isn’t enough to guarantee success – it can be very hard to convince people who have been cooking in a certain way to change their behaviour, particularly since cooking is embedded in cultures around the world, with many invisible rules and traditions that may not be immediately obvious to an outsider.
A Nigerian friend reflects on how food must be prepared with love. During cooking a dish, you have to 'stir in the spirit' to replace the energy that has been cut off from the food when it was harvested in order to nourish the body. She explained: “My grandmother was raised in a deep ancestral worshipping family (a priestess, to be exact), and she brought that into raising us, despite her religious conversion after marriage.”
Many African dishes need a lot of stirring – cooking is hard work! In Malawi, the vigorous stirring required to cook nsima can damage improved cook stoves or, worse still, tip the contents of the pot onto the cook, which can cause serious burn injuries. In some cultures where I work, there is no word in the language for “accident” and injuries can be regarded as unpreventable events that just happen.
The way we cook has an impact on climate change, as well as an intrinsic link to health. It’s obvious that what we cook and what we eat affects our health, but in addition to the problems with burns I mentioned earlier, the smoke from cooking on wood fires can cause long term damage to the lungs. The World Health Organisation estimates that inhaling smoke from cooking causes four million deaths each year; that’s ten times as many deaths from malaria.
Replacing smoky stoves with slightly less smoky stoves will probably have little impact on the number of deaths, particularly where there is no way to dispose of rubbish or crop residues apart from burning. Instead, a whole community approach is required, which tackles all the sources of smoke and comes up with safer alternatives which are acceptable to everyone. I’m working on such an approach with the Smokeless Village Project in Malawi, but progress has been hampered due to the Covid pandemic.
"The way we cook has an impact on climate change, as well as an intrinsic link to health."
One final story from Tanzania to end with, where I’m involved with a biogas cook stove project, which uses gas produced from cattle manure to replace cooking with firewood. It’s always good to hear how changing cooking practice has benefitted families. I’m used to hearing about cost savings and time saved collecting firewood, but one interview produced a surprising result. When asked about the benefits of biogas, one lady replied that it had improved her marriage! She continued: “Another thing that is really good is now my husband comes into the kitchen and we can talk about the family. Men do not like smoky kitchens, but now I can talk to my husband while I am cooking.” Her husband explained that he used to stay out of the kitchen because the smoke made his eyes water. In Maasai culture, it is shameful for an elder to be seen crying, but now he enjoys spending much more time in the kitchen with his wife and the rest of the family.