Charcoal burning

Charcoal burning was traditionally big in the iron industries of the Weald, Forest of Dean, Lake District but is now practised widely as a part of woodland management.

Until well into the twentieth century, charcoal was made mainly using earth burns or earth clamps, but kilns and retorts were developed in the seventeenth century and have no taken over except for historical re-enactment. Recently a new generation of retorts have been favoured as being more efficient conversion of timber to charcoal than kilns (and masses better than clamps) and less polluting.

Charcoal is made for a variety of purposes, including for drawing, tandoori ovens, animal feeds, filtration, and charcoal fines for biochar/soil improvement.

Wood is heated with restricted oxygen until it begins to pyrolyse or release volatile compounds these are either released into the air (clamps and kilns) or captured, burnt and the heat produced continues to convert timber to charcoal until most of the volatiles are removed. The wood is then allowed to cool and the charcoal bagged for sale.

Market issues: Cheap imports of charcoal from unsustainable sources keeping prices down

• National Coppice Federation
• Local coppice groups

As of November 2018, the Coppice Products website lists 47 makers of charcoal and bio-char, although the output of each maker is not known.