Solar Cooking
Last edited: 30 October 2018      
The article below is about a solar cooking promoter who is now deceased. This information is maintained here as a tribute to the important work done by Wietske Jongbloed.

Wietske Jongbloed

Wietske Jongbloed seated wearing black shirt

My name is Wietske Alma Jongbloed and I was born in Indonesia in 1932. I never minded getting old but these days I am sorry that I am not a couple of years younger to be able to work much longer for the advancement of solar cooking with all the inspiring solar friends I met in Varese, Kimberley, Nairobi, Nantes and Granada. You don’t find so many in the Netherlands because of the few really sunny hours.

With my family I lived twenty years in Africa (Uganda ten years, Senegal and Niger five years in each) and later I worked another five years in Niger.

My first solar cooker was a box model from Solar Cookers International, which we made in Niger in 1991 from the carton in which the fridge was packed, etc. We made several and gave a few away to Nigerians. But a box is often too cumbersome for the small houses (to stock) and also the glass plate broke easily and glass is expensive there. Also termites love carton, as well when box is made of wood.

Then the CooKit came along. Which we provide folded in a cotton bag that can be hanged on the rafters against those termites. Later in Holland we created a foundation called KoZon, which is a shortcut from the Dutch: “Koken met de Zon als warmtebron” meaning: “cooking with the energy of the sun”. We have a board of 5 persons and a couple of active advisers, we all are volunteers.

Our target countries are in the Sahel: Chad, Burkina Faso, Mali and Niger. As the CooKit is the cheapest solar cooker in Africa at the moment we think that it is the best way to learn women that solar cooking is possible. It is true that it is too small for the way food is cooked for the extended Sahelian families. But in combination with an improved stove and a large haybasket, large enough for the big pots, the CooKit is useful for many dishes which can be prepared when the sun is shining.

In the refugee camps in Chad, where our adviser Derk Rijks is the project manager, small groups of about 5 to 6 people live in the tents and there the women find the CooKit a wonderful tool as it diminishes substantially their need for firewood and as well it does the cooking nicely.

During the solar conference in Grenada one of the main questions was: why is solar cooking not accepted by so many persons who could so much benefit from it.

I think there are two reasons :

When for example you decide to spend money on a grater, to grate carrots or other vegetables, at least you can always use it when you need it. But to spend money on a solar cooker is hazardous as you can nòt always use it when you need it, breakfast, evening meal, rainy season, dust in the air . In fact I believe that this is the main reason why a person would hesitate to buy it, certainly if this person would not have much money to spend, even if (s)he thinks that it would be a fantastic tool.

It is always said or written that developing countries would so much benefit of solar cookers, especially the poor.

Years ago I read an article (but am still looking if I can find it again) about a solar cookers introduction in Lesotho (a little kingdom within South Africa) where a poor woman said: “Why do we have to work with solar cookers if the rich, who could easily buy them, are not interested”?

Margaret Owino mentioned in her presentation how in Kenya the mobile phone technology had taken everybody by storm, although they are not cheap. Here it is clear that the rich started it and that they are now used by the poorer people as well.

Agnes Klingshirn wrote in her conference article: “Addressing the more affluent urban and semi-urban population, who are looking for cheaper alternatives for the rising energy costs (electricity, L.P.G., kerosene, charcoal) and can afford to buy solar cookers, can demonstrate the value of the new technology well”.

That is why in Niger I am trying to convince some women who are working and get a salary to buy a HotPot (available from the Solar Household Energy, Inc. agent in Mali). If the richer people will solar cook, the poorer will follow sooner, even using a cheaper cooker like the CooKit. I am quite sure about that.

News and recent developements[]

  • October 2018: Solar Cooking KoZon schrijft: Begin oktober bereikte ons het droeve bericht dat Wietske Alma Jongbloed, de oprichtster van de Stichting KoZon, op 86-jarige leeftijd is overleden. Ruim 15 jaar heeft zij zich met grote kennis van zaken ingezet om het leven van vrouwen in Afrika te verbeteren. Vanaf de oprichting van KoZon in 1998 heeft ze enorm hard gewerkt om zoveel mogelijk vrouwen in West-Afrika de kans te geven gebruik te maken van de CooKit, de hooimand, een hout besparend kooktoestel en een WAPI. Deze geïntegreerde aanpak leidde tot flinke besparingen op brandhout en tot een veiliger en gezonder leven voor duizenden vrouwen en kinderen. Het werkgebied van KoZon breidde zich uit toen Derk Rijks, mede op initiatief van Wietske, en met steun van KoZon, het zonnekoken in een aantal vluchtelingenkampen in Tsjaad introduceerde. In 2004 startte Solar Cooking Nederland (SCN) met zonnekoken in Oost-Afrika, met begeleiding en advies van Wietske.
Idadafoua in Niger 2007.jpg
  • November 2007: At the 2006 International Solar Cookers Conference in Spain, Wietske Jongbloed of the KoZon Foundation learned a useful trick from David and Ruth Whitfield: a heat-retention cooker can be made from empty rice bags. The Whitfields advised that two large rice bags, with insulation such as wool or cotton in between, make a sack that will keep a pot of food at cooking temperatures long after it is removed from a heat source. KoZon introduced the idea in Tahoua, Niger, where cooking pots are typically very large — 12 to 16 liters. For these pots, four rice bags are needed to surround the pot, and a fifth bag stuffed with insulation covers the top. Of this five-bag system, Jongbloed says, “It is named ‘Idadafoua’ and works marvelously.” Jongbloed writes that women in the Sahel cook meals for families of 10 to 12 or more people. The KoZon project in Tahoua teaches the use of three cooking devices — fuel-efficient wood stoves, heat-retention cookers, and solar CooKits. CooKits are used on sunny days for meat or fish sauces, eggs, sweet potatoes, and groundnuts, and for cakes that are sold by the slice to earn money.
  • November 2006: Wietske Jongbloed reports that she and a team of three others in Tahoua trained 14 women, all teachers and civil servants, in the complimentary technologies of solar cookers, fuel-efficient wood stoves, and heat-retention cookers. The first two days of the training were cloudy, so the focus was on fuel-efficient stoves ("poêle économe") and heat-retention cookers ("bitatoré"). Heat-retention cookers are insulated enclosures in which is set a pot of food that has been brought to a boil, allowing the food to continue to cook after being removed from the heat source. Rice, meat, and legume dishes were cooked successfully using this method. On days three and four the sun started to shine. Peanuts and sweet potatoes were cooked in solar CooKits and shared with five visiting directors of ministries. The directors praised the solar-cooked food, along with the dishes prepared with the other devices. Jongloed recalled, "They asked where the cooked peanuts were, which I thought were meant for the children, and just ate the peanuts up and praised the CooKit in which the peanuts were cooked and made speeches telling us that they would help in all ways if the women of Tahoua could all be taught to use these complimentary devices." On the final day, several banana cakes were baked in CooKits, as were a couple dozen eggs. After the 14 women gain more experience using the three complimentary devices, several of them will be chosen to lead future training. The goal is to train close to 200 women, and to provide them each with a CooKit. Affordable purchase plans for the fuel-efficient stoves and heat-retention cookers are being explored.

Audio and video[]

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Wietske Jongbloed
Stichting KoZon
Hollandseweg 384
6705 BE Wageningen

Tel: 31-317412370