In pictures: Charcoal in Chad

Once the charcoal arrives in the cities, it must be delivered quickly to customers. Mahamat is 50, and charcoal selling is a family tradition.

He starts work at dawn each day, and is finished by mid-morning.

"I like my work," says Mahamat, "except for the problem I have with forest controllers.

"Because there is no official tax rate, they just make the price up. They used to charge 20 US cents per sack to bring charcoal out of the forest but now they want 60."