How it Works
1) Rubbish collection: A community, or specific groups or individuals collect rubbish in baskets, bags and wheelbarrows.
2) Sorting Rubbish: Rubbish is deposited and sorted on the lowest of the three stepped steel welded mesh racks. Rubbish sorters receive training in solid waste management to ensure that non-combustible materials and material which create harmful fumes are intercepted and removed, such as torch batteries, glass and rubber. Biodegradable scraps that fall through become compost manure. The remaining rubbish such as plastic bags, packaging, food scraps and even flying toilets, are placed on the second tiered rack for drying. Dry materials are shovelled down the chute to the firebox.
3) Incineration: Two simple taps are the only moving controls on the cooker: one tap controls a drip flow of recycled sump oil (discarded oil from vehicles) and one tap controls a drip flow of water. A drop of each, in equal amounts, falls onto the super-heated steel plate of the firebox, where the water vaporizes and boosts the flames, thereby increasing the temperature from about 250 degrees Celsius to more than 800 degrees Celsius (the World Health Organisation (WHO) minimum burning standard for incinerators in developing countries). As the firebox gets hotter, the network of steel pipes that pass around the cooker produce hot water. As the rubbish burns, heat is distributed under 8 cooking plates on the top of the Cooker and 2 ovens in the sides of the Cooker.
4) Using rubbish as fuel: The cooker can be used 24/7 by individuals or community groups to cook food for their own use or as an income generating activity. The cooker has a cooking surface of 1.7 square meters, two large ovens for baking, and storage capacity for heating 800 litres of water at any given time. Each oven is large enough to bake up to 10 loaves of bread at one time or roast an entire goat.
5) Cleaner waste: A ten-metre-tall chimney rises out of the combustion chamber and above the neighbourhood rooftops. Because the flames are boosted by the regulated mixture of sump oil and water, the firebox and combustion chamber achieve ninety-nine percent combustion efficiency (Société Générale Surveillance Kenya, Environmental Measures Report NRB1152-0094, 21 March 2011). As a result, the chimney emits a nearly odourless white vapour when the stove is in use.
6) Maintenance: Once all the rubbish in the combustion chamber has been burned and the users are ready to turn off the Cooker, one simply turns off the oil and water drip feed and stops feeding the rubbish through the chute. At the end of a burn, the operator should use a pipe or shovel to remove the ash below the firebox and combustion chamber. The ash can be used for block making.