Bioenergy Production from Perennial Energy Crops: A Consequential LCA of 12 Bioenergy Scenarios including Land Use Changes

• Published in: Environmental science & technology Vol. 46; no. 24; pp. 13521 - 13530
• Main Authors: Tonini, Davide, Hamelin, Lorie, Wenzel, Henrik, Astrup, Thomas
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 18.12.2012
• Subjects: Agriculture; Air pollution caused by fuel industries; Anaerobiosis; Animals; Applied sciences; Biofuels - analysis; Biomass; Carbon - analysis; Carbon Dioxide - analysis; Crops; Crops, Agricultural - growth & development; Emissions; Energy; Energy. Thermal use of fuels; Environmental impact; Exact sciences and technology; Fuel processing. Carbochemistry and petrochemistry; Fuels; Global Warming; Land use; Manure - analysis; Metering. Control; Natural energy; Nitrogen - analysis; Solid fuel processing (coal, coke, brown coal, peat, wood, etc.); Sus scrofa; Sustainable development; Denmark; Monocotyledones; Cogeneration; Ecobalance; Lolium; Heat production; Combustion; Biomass; Pollutant emission; Energy plantation; Anaerobic digestion; Land use; Gramineae; Environment impact; Angiospermae; Co-combustion; Spermatophyta; Bioenergy; Gasification; Herbaceous plant; Electric power production
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es3024435

In the endeavor of optimizing the sustainability of bioenergy production in Denmark, this consequential life cycle assessment (LCA) evaluated the environmental impacts associated with the production of heat and electricity from one hectare of Danish arable land cultivated with three perennial crops: ryegrass (Lolium perenne), willow (Salix viminalis) and Miscanthus giganteus. For each, four conversion pathways were assessed against a fossil fuel reference: (I) anaerobic co-digestion with manure, (II) gasification, (III) combustion in small-to-medium scale biomass combined heat and power (CHP) plants and IV) co-firing in large scale coal-fired CHP plants. Soil carbon changes, direct and indirect land use changes as well as uncertainty analysis (sensitivity, MonteCarlo) were included in the LCA. Results showed that global warming was the bottleneck impact, where only two scenarios, namely willow and Miscanthus co-firing, allowed for an improvement as compared with the reference (−82 and −45 t CO2-eq. ha–1, respectively). The indirect land use changes impact was quantified as 310 ± 170 t CO2-eq. ha–1, representing a paramount average of 41% of the induced greenhouse gas emissions. The uncertainty analysis confirmed the results robustness and highlighted the indirect land use changes uncertainty as the only uncertainty that can significantly change the outcome of the LCA results.