Bioethanol from poplar clone Imola: an environmentally viable alternative to fossil fuel?
BACKGROUND
Environmental issues, e.g. climate change, fossil resource depletion have triggered ambitious national/regional policies to develop biofuel and bioenergy roles within the overall energy portfolio to achieve decarbonising the global economy and increase energy security. With the 10 % binding target for the transport sector, the Renewable Energy Directive confirms the EU's commitment to renewable transport fuels especially advanced biofuels. Imola is an elite poplar clone crossed from Populus deltoides Bartr. and Populus nigra L. by Research Units for Intensive Wood Production, Agriculture Research Council in Italy. This study examines its suitability for plantation cultivation under short or very short rotation coppice regimes as a potential lignocellulosic feedstock for the production of ethanol as a transport biofuel. A life cycle assessment (LCA) approach was used to model the cradle-to-gate environmental profile of Imola-derived biofuel benchmarked against conventional fossil gasoline. Specific attention was given to analysing the agroecosystem fluxes of carbon and nitrogen occurring in the cultivation of the Imola biomass in the biofuel life cycle using a process-oriented biogeochemistry model (DeNitrification-DeComposition) specifically modified for application to 2G perennial bioenergy crops and carbon and nitrogen cycling.


RESULTS
Our results demonstrate that carbon and nitrogen cycling in perennial crop-soil ecosystems such as this example can be expected to have significant effects on the overall environmental profiles of 2G biofuels. In particular, soil carbon accumulation in perennial biomass plantations is likely to be a significant component in the overall greenhouse gas balance of future biofuel and other biorefinery products and warrants ongoing research and data collection for LCA models. We conclude that bioethanol produced from Imola represents a promising alternative transport fuel offering some savings ranging from 35 to 100 % over petrol in global warming potential, ozone depletion and photochemical oxidation impact categories.


CONCLUSIONS
Via comparative analyses for Imola-derived bioethanol across potential supply chains, we highlight priority issues for potential improvement in 2G biofuel profiling. Advanced clones of poplar such as Imola for 2G biofuel production in Italy as modelled here show potential to deliver an environmentally sustainable lignocellulosic biorefinery industry and accelerate advanced biofuel penetration in the transport sector.
Department of Chemical Engineering, Imperial College London, London, SW7 2AZ UK ; Department of Life Sciences, Imperial College London, London, SW7 2AZ UK.
Miao
0000-0001-7733-5077
M
Guo
Institute for the Study of Earth, Oceans, and Space, Morse Hall, University of New Hampshire, Durham, NH 03824 USA.
Changsheng
C
Li
Research Units for Intensive Wood Production (PLF), Agriculture Research Council (CRA), Casale Monferrato, Italy.
Gianni
G
Facciotto
Research Units for Intensive Wood Production (PLF), Agriculture Research Council (CRA), Casale Monferrato, Italy.
Sara
S
Bergante
Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Ceredigion SY23 3EB UK.
Rakesh
R
Bhatia
Department of Environmental and Land Sciences, Milano Bicocca University, Milan, Italy.
Roberto
R
Comolli
Department of Environmental and Land Sciences, Milano Bicocca University, Milan, Italy.
Chiara
C
Ferré
Department of Life Sciences, Imperial College London, London, SW7 2AZ UK ; Centre for Environmental Strategy, University of Surrey, Guildford, Surrey, GU2 7XH UK.
Richard
R
Murphy
2G biofuel; Bioethanol; Biogeochemistry model; Carbon and nitrogen cycling; DNDC; Life cycle assessment; Perenial bioenergy crop; Poplar; Supply chain