Solar-Powered Cookers offer sustainable solution in Kenya

For street food vendor Ian Duncun Onyango, it's part of his business. He cooks up boiled eggs and smokies (smoked sausages) for passersby in Nairobi. It saves him money and so boosts his profits.

The local solar powered oven was developed by entrepreneur Carolyn Olang. She saw an opportunity in the market for such an invention. In sub-Saharan Africa around 90% of the population use firewood and charcoal. In Kenya around 12 million households - or around 67% of the population - cook using firewood and charcoal. According to the World Health Organization, the method has been associated with health problems and climate change.

The smoke that emanates from charcoal and firewood can cause health problems and cutting down trees for firewood and charcoal contributes to deforestation. The solar oven is relatively easy to make. It is basically two wooden boxes, one smaller than the other. In between them is a thick layer of a heat absorber, like chicken corn husks. Then on top is a glass sheet with an aluminium covered panel to reflect the light into the box where the cooking happens.

Olang estimates the cost to produce one is around Ksh, 3,500 (USD $35) and she's selling them for Ksh,5,000 (USD $50) to break into the market. She says the benefits are that solar power is free, the oven doesn't produce smoke, and it helps combat climate change. But Olang admits some drawbacks. "The shortcomings are that during the rainy season, you can't use it because you can't put it out in the rain, and another thing, the sun won't be shining throughout. But when you consider that in Africa more often than not it is sunny, sunny Africa, I think it is a good alternative to the traditional methods of cooking using firewood and charcoal which is what most households use," she says.

Globally, there are around 2.5 billion people who cook using firewood and charcoal as their main source of energy which is a major cause of climate change and pollution.