Abstract

Urban slum kitchens use bio-fuel, which emanates smoke and black carbon. Expensive eco-stoves available in the market do not make use of India’s perennial supply of warm sunshine to improve their efficiency. This forms the basis of our study. We propose a radical remoulding of slum kitchens, aimed at efficient bio-fuel burning and sunlight assisted seasoning in a desiccation chamber. This is possibly the first design anywhere in the world and has been funded by Villgro under the Young Innovator Programme. First, we use ecotect analysis to configure optimal daylighting, form and fabric of these kitchens. The results suggest that in Northern Hemisphere, the preferred orientation is south or south westerly. It is observed that such a chamber made of glass provides a temperature increase of 14 degrees C above the ambient. This will increase seasoning efficiency because the humidity content is lowered by 20%, causing a substantial decrease in smoke emissions. We base this study on Chennai city, where roughly 2 million people reside in slums. We use a USEPA plume dispersion model that accounts for the undulating topography, land and sea breeze effects, and most importantly, building downwash effects. The latter effect is important, particularly because the Chennai slums are located adjacent to high-rise buildings, causing a blocking flow. Finally, we present an environmental impact assessment analysis on emissions of these bio particles over distributed area sources, with and without the presence of the desiccation assisted eco stoves in slum kitchens. A cost benefit model is also presented to highlight economic gains that the Chennai city corporation would achieve if it provided a green subsidy for construction adaptation and proliferation of these new kitchen designs. We estimate that a reduction of approximately 50% in soot carbon emission can be achieved in less than 50 USD.