The Kyoto Box solar Oven is an invention that so simple, and so inexpensive, yet it could have a huge impact:

The basic problem that this simple invention is trying to solve has to do with cooking fuel. In the developing world, the process of gathering cooking fuel takes a lot of time. Usually the fuel is wood or dung. Cooking over a smoky fire also creates a lot of health problems (from inhaling the smoke). And in overpopulated areas, cutting wood can cause deforestation (as described here).

The Kyoto Box solar oven addresses all three problems by eliminating the fuel and the smoke. It is claimed that the oven can boil 10 liters of water in two to three hours, and boiling or near-boiling water can cook beans, rice, grains and meat. Because cardboard is a fairly good insulator, the Kyoto Box solar oven can also act as an insulated place to keep food warm once the cooking is done. The simplicity of this invention is its genius.

More info:
- Inventor turns cardboard boxes into eco-friendly oven
- Solar Cooker Heats Up $75K Climate Change Contest

See also: DIY – make your own mini wood stoves

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