Fuel from the Fields: Charcoal from agricultural waste
Practical Action
• Hit the bottom of the press on a hard surface (e.g. the surface of the hammering station).
This pushes the ejector pin upwards, and lifts the briquette upwards.
• Repeat until you have made briquettes with all the material.
A lot of charcoal mixture will fall on the ground during this process; if you put a plastic sheet or tightly
woven cloth down where you are working, you can use it to collect the charcoal mixture to use it to make
one final briquette, so it isn’t wasted.
Drying the briquettes
These briquettes, now formed, will need to dry in the sunshine, to fully harden.
• Leave the briquettes to dry in the sun for at least 2 days. If rain is likely, make sure they
are protected from the water.
Hardening the briquettes (optional step):
After briquettes have dried in the sun, they may still be soft. To harden the briquettes, you can
fire them in an oil drum, while making another batch of charcoal. Put the briquettes in a wire
mesh basket, and gently toss the basket in a burning oil drum, just before you put the lid on and
seal it. When you open the drum after 2 hours, the briquettes in the mesh basket will have baked,
and hardened.
Complete
These fully formed briquettes (figure 17) are now
ready for use. They can be used in a normal
stove, or can be transported and sold at market.
Figure 17: Charcoal briquettes, ready to use.
Photo credit: Fuel from the Fields.
Conclusion
Household fuel use is a major energy problem in the developing world. Cooking with biomass
(which is free) is associated with childhood pneumonia; the leading cause of childhood death
across the world. Wood charcoal made traditionally is a clean alternative, but can be expensive,
and is also associated with deforestation.
The FftF technique allows clean-burning charcoal to be made from previously unused agricultural
waste, either for personal use, or to sell at market. It allows poor farmers to make a profit from
previously worthless crop waste. The technology is simple, cheap and quick, and uses locally
available materials. We have outlined the process required, to allow field-workers to produce
charcoal of their own and to run training sessions.
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