|SHISA STOVE TESTS|
The Shisa Stove was tested in December 2002 by Vivienne Abbott (Tanzania) who did a few cooking tests for GTZ (ProBEC) in a village near Polekwane, Limpopo Province, South Africa.
While the stove performed as expeected, one of the unusual portions was the boiling and simmering of 2 litres of water using only dung as a fuel. The preheating of the primary air is believed to cause the dung to pyrolize at a temperature high enough, and in an enclosed environment, that it can burn properly and completely - something it rarely does unless it is mixed with other fuels.
The testing compared an open fire, a modified Mali Stove (which it turns out is in fact a charcoal stove though they were burning wood in it), an Eco Stove (basically a stainless steel, two pot Rocket Stove with an integrated oven), a Rocket Stove (á-la Aprovecho) and the Shisa Stove which they called a Swazi Stove in their document.
The Shisa Stove is designed to burn wood up to 110mm in diameter and up to 140mm long. It has provision for preheating the primary and secondary air. Nearly all the available heat contained within the biomass fuel can be liberated. It also means there there is less smoke, particulate matter and Carbon Monoxide (CO) emitted, compared with most other stoves and open fires.
The Shisa Stove is constructed from a custom made 25 litre paint can. It has three grooves in the sides which provide support for components at certain points. This allows for the stove parts to be nested for shipment and later assembled without welding. There is a top deck which supports the pot rest, a rotating ring-shaped air controller, a secondary air preheating tube and a basket-type fire grate. Inside the top section there is a flame shield to protect the outside top of the stove from heating up too much and to reflect the flame's heat back to the pot. The pot (up to a No. 2 cast iron three legged pot or any flat bottomed pot up to 230mm in diameter) sits inside the upper section to receive maximum heat transfer and to shelter from the wind.
The average fuel load is between 300 and 900 grammes of wood.