Institutional Improved Cook Stoves (IICS) minimize the problem of dirty smoke generated from burning firewood and alarming deforestation rates. There are many species of trees all with different forms based on their varying fiber structures and densities. This means they differ in the ways they can be used and also the amounts of energy they store. Firewood does not always contain the same amount of energy. The main reason for this is the water that is stored inside it:
Fresh wood contains up to 50% of water, and water does not burn.
When firewood is dried for one year, its calorific value doubles, having the water content decrease from 50% up to 15%
Burning dry firewood with efficient combustion results in clean burning with few particles. When firewood burns, three things happen:
1. Water is removed by evaporation
2. Chemically, the firewood breaks down into charcoal, gas and volatile liquids, with carbon dioxide and water being the chief end products
3. The charcoal burns, forming carbon dioxide either directly or with an intermediate conversion to carbon monoxide.
Educating schools and kitchen staff on how best to store firewood is one of the many aspects involved in our training programme. Here below, a picture that clearly shows the bubbles in the firewood stick while burning, that result from a high water content. This in not a one-off session, but an on-going exercise that is documented, with those involved during the kitchen visits signing the training sheets.
