Three-in-one oven

From SciDev.net Researchers trial 'three-in-one' oven:

"A new 'three-in-one' stove that provides electricity as well as acting as a cooker and refrigerator is undergoing field trials in Nepal and the United Kingdom.

Developed by scientists at the UK-based University of Nottingham, the stove harnesses 'thermoacoustic' energy.

A fire at one end of a gas-filled pipe creates a temperature gradient, which triggers sound waves as gas moves from hot to cold regions, similar to a 'singing' kettle. The mechanical energy of the sound waves is then converted into electrical energy.

A separate thermoacoustic engine works in reverse to generate a cooling effect for the refrigerator, and food can be cooked on the heat from the fire. All three processes can occur simultaneously.

The oven is more efficient than similar devices and can be built using local materials, as recent tests in Nepal using propane as the energy source showed.

The team are hoping to develop a generator that runs on biomass — wood or dung for example — and weighs between ten and 20 kilograms, at a cost of no more than £20 (US$33). They believe that communities in the Indian subcontinent, Sub-Saharan Africa and South America could benefit from the stove.

The project, known as SCORE (Stove for Cooking, Refrigeration and Electricity Supply) was launched two years ago."
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