It’s a tough exercise, getting cooks to chop the firewood to small pieces. It is understandable because they have been used to cooking with huge wood logs in the past when using 3-stone fires.
But the institutional improved cook stoves (IICS) do not need such big pieces of wood. Actually they can damage the combustion chamber, because they are very heavy and break the supporting bricks and grates.
Big wood logs DO NOT cook faster. Contrary to what most cooks believe, big logs only asphyxiate the firewood entrance, blocking aeration and making combustion more difficult. Below is a short video showing the right wood diameter and number of sticks needed to have the perfect combustion, as Kitebi Primary School cooks their beans in a 350 litres saucepan capacity.