Open AccessCO 2 emissions from biomass combustion for bioenergy: atmospheric decay and contribution to global warming
Author(s) -
CHERUBINI FRANCESCO,
PETERS GLEN P.,
BERNTSEN TERJE,
STRØMMAN ANDERS H.,
HERTWICH EDGAR
Publication year - 2011
Publication title -
gcb bioenergy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.378
H-Index - 63
eISSN - 1757-1707
pISSN - 1757-1693
DOI - 10.1111/j.1757-1707.2011.01102.x
Subject(s) - bioenergy , environmental science , biomass (ecology) , biofuel , combustion , global warming , greenhouse gas , climate change , atmospheric sciences , carbon cycle , carbon neutrality , ecosystem , ecology , waste management , chemistry , engineering , organic chemistry , biology , geology
Carbon dioxide (CO 2 ) emissions from biomass combustion are traditionally assumed climate neutral if the bioenergy system is carbon (C) flux neutral, i.e. the CO 2 released from biofuel combustion approximately equals the amount of CO 2 sequestered in biomass. This convention, widely adopted in life cycle assessment (LCA) studies of bioenergy systems, underestimates the climate impact of bioenergy. Besides CO 2 emissions from permanent C losses, CO 2 emissions from C flux neutral systems (that is from temporary C losses) also contribute to climate change: before being captured by biomass regrowth, CO 2 molecules spend time in the atmosphere and contribute to global warming. In this paper, a method to estimate the climate impact of CO 2 emissions from biomass combustion is proposed. Our method uses CO 2 impulse response functions (IRF) from C cycle models in the elaboration of atmospheric decay functions for biomass‐derived CO 2 emissions. Their contributions to global warming are then quantified with a unit‐based index, the GWP bio . Since this index is expressed as a function of the rotation period of the biomass, our results can be applied to CO 2 emissions from combustion of all the different biomass species, from annual row crops to slower growing boreal forest.