Student invents low-cost multi-purpose oven

By Brian OurienIT is said that necessity is the mother of all invention, and invention is the engine of development. Development and cost cutting is what David Tebandeke, a second year student of Electrical Engineering at Kyambogo University, had in mind when he set out to make a multipurpose oven.His fabrication operates like a modern electrical oven, but uses charcoal. The oven, made out of steel, is insulated with fibre-glass wool to reduce heat loss.The heaters, which are removable, are not in direct contact with the main body. This allows the oven to have a long life-span.The heat does not affect the main body. The vertical heaters are taken out of the oven and filled with charcoal, which is then lighted outside the oven. The heaters are then placed back into the oven and the door closed.This allows for even distribution of heat throughout the oven. The insulation also ensures minimal use of charcoal.A spadeful of charcoal, worth sh200, can run the oven for four hours. During this period, it can roast 16 chickens, two every 30 minutes.A bigger oven, sufficient to load 100 family size loaves of bread, can operate on two medium size tins of charcoal worth sh 2,000 for four hours. Since bread can get ready within thirty minutes, that amount of charcoal can bake 800 loaves of bread.The multi-purpose ovens are designed to last up to 20 years with minimum regular maintenance on the heaters. It can generate temperatures of between 100°C and 300°C and takes between 15 to 45 minutes to get to 300°C. The oven can work continuously for over 24 hours.The smaller oven is being used successfully at Namere Take-away in Bweyogerere. The take-away owner says it is efficient and saves charcoal, time and labour. “I’m satisfied with it,” he says. Tebandeke developed the idea in 1999 and built his first oven in October 2001. He does not have a workshop as yet but hires workshops to build the ovens. He also lacks capital for mass production.The small oven goes for sh300,000, while the big one that can bake 100 loaves goes for sh3m.“I thought of it because I wanted to add value to things like roasting and baking using the most economical source of energy available, but which is profitable at low costs and low labour,” Tebandeke says.He intends to mass-produce them so that they can be used widely, as well as to promote the effective use of biomass energy.ends