An important criterion for bioenergy systems evaluation is their greenhouse gas mitigation potential. Sugarcane bioenergy systems are able to produce grid-bound surplus electricity but also have net CO2 emissions associated with the upstream fossil-fuel consumption for plantation management, transportation and processing of the fibrous biomass. However, when compared to coal-based power generation systems, sugarcane bioenergy systems are able to avoid CO2 emissions at rates that range between 1.081 and 1.137 kg CO2/k Wh depending on the cane-residue utilisation strategy adopted. As a consequence, sugarcane bioenergy systems stand out as promising energy projects for funding under the Kyoto Protocol's proposed clean development mechanism and joint implementation.