Global agreements in support of renewable sources of energy are driving increasing demand for biomass fuels. However, there is limited quantitative information on metal emission from biomass fuels combustion, particularly those measured in field in developing countries, causing insufficient information in the evaluation of the environmental impact of biomass fuels combustion. This study was performed to compare the emission characteristics of metals (Cu, Cd, Pb, Ni, As) from biomass pellets and uncompressed biomass fuels burnt in residential household in rural China. Results showed that metal concentrations in flue gas and bottom ash from biomass pellets were mostly higher than uncompressed biomass fuels. However, when energy-based metal emissions were calculated, metal emissions from biomass pellets were mostly close to or lower than uncompressed fuels. Therefore, delivering unit energy using biomass pellets would produce less metal emissions than uncompressed biomass fuels.
