Firewood and charcoal supply: Impact on the biosphere

Vanishing woodland, smoky kilns and heavy loads

What this tab covers Effects on human, animal, plant, fungal and microbial life and on whole ecosystems: in the short term (construction and early years), medium term (operating life) and long term (decommissioning and legacy).

Unsustainable charcoal and firewood harvesting clears and degrades woodland, and kilns release methane and carbon monoxide.

Methane from a mound kiln (Cote d'Ivoire study) About 40 g per kg of charcoal³ Carbon monoxide from a mound kiln (same study) About 233 g per kg of charcoal³ Forest loss linked to charcoal, Tanzania 100,000 to 125,000 ha per year⁴ Earth kilns used each year, Tanzania About 160,000⁴ Deaths a year from household air pollution About 3.2 million⁹

Effects over time

Life affected	Short term	Medium term	Long term
Humans⁵⁹¹⁰	Heavy loads (about 50 to 60 kg) and long walks for wood collection; kiln smoke exposure for producers	Low incomes (about USD 0.50 per hour in Kenya); smoke from cooking with wood and charcoal contributes to about 3.2 million deaths a year from household air pollution	Loss of woodland reduces future fuel and income
Animals⁴	Disturbance from cutting	Habitat loss as woodland is degraded; magnitudes not quantified in sources found	Little evidence of effect
Plants⁴	Felling of trees for kilns	About 30 million cubic metres of wood a year for Tanzania's charcoal	Regrowth possible if land is not converted to farms
Fungi and soil life³	Soil heated and burned under kilns	Little evidence of effect	Little evidence of effect
Ecosystems³⁴	Clearing near roads and cities	100,000 to 125,000 hectares of forest lost a year in Tanzania	Climate effect from methane and non-renewable harvest

How the effects are reduced

Improved kilns roughly double the charcoal from each tree. Community forest management with legal, traceable harvest and royalties lets woodland regrow. Plantations and woodlots move harvesting off natural forest. On the demand side, efficient stoves and switching to LPG or electricity reduce both wood use and smoke.

Sources

Review of technologies for the production and use of charcoal (Kammen and Lew) Renewable and Appropriate Energy Laboratory, UC Berkeley, 2005
Environmental Crisis or Sustainable Development Opportunity? Transforming the Charcoal Sector in Tanzania: A Policy Note World Bank, 2009
Sustainable Business Models for Tree-based Value Chains in Sub-Saharan Africa: Analysis of the Charcoal Value Chain in Kenya (Mutta) Swedish University of Agricultural Sciences (SLU), Formas project, 2020
Household air pollution: health risks World Health Organization, 2026
Women's work is never done: lifting the gendered burden of firewood collection and household energy use in Kenya (Njenga, Gitau and Mendum, Energy Research and Social Science 77) Elsevier, 2021