Uganda is dying because of deforestation. Its women are terribly affected by smoke from cooking fires.
He has devised a zero-cost mud stove that reduces firewood use to half, and eliminates indoor smoke.
The description took me back to my mudsmith days, and is very similar to mud pizza ovens we in Australia build for fun. In Uganda, though, the technique is used for survival.
More strength to Badru Kyewalyanga.
Photograph: Jake Lyell/Alamy