Indirect carbon dioxide emissions from producing bioenergy from forest harvest residues

摘要: Forest harvest residues are important raw materials for bioenergy in regions practicing forestry. Removing these from a site reduces the carbon stock of forest compared with conventional stem-only because less litter left on site. The indirect dioxide (CO 2 ) emission producing occur when logging is emitted into atmosphere at once through combustion, instead being released little by as result decomposition sites. In this study (1) we introduce an approach to calculate using production, and (2) estimate typical target residue removal, i.e. boreal Norway spruce Finland. removal stumps caused larger per unit energy produced than branches lower rate stumps. decreased time since starting collect older During 100 years conducting practice, average-sized (diameter cm) 340 70 kg CO eq. MWh ―1 that 26 160 . These emissions order magnitude other (collecting, transporting, etc.) production chain. When was started, total were comparable fossil fuels. practice had be carried out 22 (stumps) or four (branches) until dropped below natural gas. Our results emphasize importance accounting land-use-related correctly efficiency reducing atmosphere.