Improvements in charcoal production and the environmental implications: Potential for the invasive Prosopis juliflora in Kenya

•Invasive Prosopis juliflora has potential for sustainable biomass for charcoal.•Small stems and branches of trees produce good quality charcoal hence save trees.•Drying wood well enhances charcoal yield and reduces emissions during production.•Capacity development and effective communication is needed for sustainable charcoal. Charcoal is a common woodfuel in sub-Saharan Africa (SSA). Unsustainable wood sourcing and inefficient carbonization result into negative environmental impacts. This action research aimed at building the capacity for sustainable charcoal production including `improving the traditional earth mound kiln (TEK) that is used by 99% of charcoal producers in Kenya. Small stems and branches of the invasive Prosopis juliflora were used and produced quality charcoal with 28 kJ/g which will save trees. Improved earth mound kiln (IEK) increased charcoal yield by 49% per mass of sun dried wood fed into the kiln and reduced emissions of carbon monoxide, carbon dioxide and hydrocarbons by 40%, 49% and 44% respectively. Net charcoal yield by a mass of dry wood in TEK and IEK was 26.4% and 28.4% respectively. Communication and capacity development on sustainable charcoal benefit people and environment. Studies on sustainable charcoal and effects on dryland socio-ecological systems will be needed.