Current limits of life cycle assessment framework in evaluating environmental sustainability – case of two evolving biofuel technologies

Abstract The growing need to use biofuel raw materials that do not compete with food and feed have resulted in a growing interest in lignocellulosic materials and microalgae. However, the life cycle environmental benefits of both biofuels have been questioned. The aim of this study was to evaluate how environmental sustainability of forest-based and microalgae biodiesel can be estimated by using the life cycle assessment framework. These biofuel chains were chosen because they are contrasting systems, as the first one is based on a “natural” feedstock production system, while the second one is an entirely anthropogenic system using an artificial infrastructure and external inputs to grow microalgae. This study focuses on life cycle impact categories still under methodological development, namely resource depletion, land use and land use change, water use, soil quality impacts and biodiversity. In addition, climate impacts were quantified in order to exemplify the uncertainty of the results and the complexity of estimating the parameters. This study demonstrates the difficulty to assess the absolute range of the total environmental impacts of the two systems. The results propose that the greenhouse gas emissions of microalgae biodiesel are higher than those of forest residue-based biodiesel, but the results of the microalgae chain are very uncertain due to the early development stage of the technology, and due to assumptions made concerning the electricity mix. On the other hand, the microalgae system has other advantages such as low competition on productive land and low biodiversity impacts. The findings help to recognise the main characteristics of the two production chains, and the main remaining research issues on bioenergy assessment along with the methodological development needs of life cycle approaches.

[1]  Mark A. White,et al.  Environmental life cycle comparison of algae to other bioenergy feedstocks. , 2010, Environmental science & technology.

[2]  R. Clift,et al.  Soil Organic Carbon Changes in the Cultivation of Energy Crops: Implications for GHG Balances and Soil Quality for Use in LCA , 2011 .

[3]  S. Soimakallio.  Assessing the uncertainties of climate policies and mitigation measures. Viewpoints on biofuel production, grid electricity consumption and differentiation of emission reduction commitments , 2012 .

[4]  Margareta Wihersaari,et al.  Aspects on bioenergy as a technical measure to reduce energy related greenhouse gas emissions , 2005 .

[5]  Sampo Soimakallio,et al.  Greenhouse gas balances and new business opportunities for biomass-based transportation fuels and agrobiomass in Finland , 2009 .

[6]  Ottar Michelsen,et al.  Assessment of land use impact on biodiversity: Proposal of a new methodology exemplified with forestry operations in Norway , 2008 .

[7]  T Wiesenthal,et al.  How much bioenergy can Europe produce without harming the environment , 2006 .

[8]  Jari Liski,et al.  Heterotrophic soil respiration—Comparison of different models describing its temperature dependence , 2008 .

[9]  Jari Liski,et al.  Indirect carbon dioxide emissions from producing bioenergy from forest harvest residues , 2011 .

[10]  Pekka Leskinen,et al.  Uncertainty in environmentally conscious decision making: beer or wine? , 2012, The International Journal of Life Cycle Assessment.

[11]  D. M. Tillett,et al.  Design and operation of an outdoor microalgae test facility , 1989 .

[12]  Jacinto F. Fabiosa,et al.  Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change , 2008, Science.

[13]  E. Hertwich,et al.  Affluence drives the global displacement of land use , 2013 .

[14]  T. Koellner,et al.  Rarefaction method for assessing plant species diversity on a regional scale , 2004 .

[15]  Bo Pedersen Weidema,et al.  Data quality management for life cycle inventories—an example of using data quality indicators☆ , 1996 .

[16]  J. Liski,et al.  Leaf litter decomposition-Estimates of global variability based on Yasso07 model , 2009, 0906.0886.

[17]  Arnaud Hélias,et al.  Life-cycle assessment of biodiesel production from microalgae. , 2009, Environmental science & technology.

[18]  Sarah Sim,et al.  Land use impact assessment of margarine , 2012, The International Journal of Life Cycle Assessment.

[19]  A. Holma,et al.  Assessing environmental impacts of biomass production chains - application of life cycle assessment (LCA) and multi-criteria decision analysis (MCDA). , 2012 .

[20]  Gjalt Huppes,et al.  Life cycle assessment of flax shives derived second generation ethanol fueled automobiles in Spain , 2009 .

[21]  Ottar Michelsen,et al.  Impact Assessment of Biodiversity and Carbon Pools from Land Use and Land Use Changes in Life Cycle Assessment, Exemplified with Forestry Operations in Norway , 2012 .

[22]  Thomas H. Bradley,et al.  Quantitative measurement of direct nitrous oxide emissions from microalgae cultivation. , 2011, Environmental science & technology.

[23]  Nigel W.T. Quinn,et al.  A Realistic Technology and Engineering Assessment of Algae Biofuel Production , 2010 .

[24]  L. Lardon,et al.  Life-cycle assessment of microalgae culture coupled to biogas production. , 2011, Bioresource technology.

[25]  Manuele Margni,et al.  Assessment of land use impacts on soil ecological functions: development of spatially differentiated characterization factors within a Canadian context , 2011 .

[26]  Mary Stewart,et al.  A Consistent Framework for Assessing the Impacts from Resource Use - A focus on resource functionality (8 pp) , 2005 .

[27]  Rabbe Thun,et al.  Identification and quantification of indirect land and resource use changes – Challenges caused by expanding liquid biofuel production , 2012 .

[28]  T. Koellner,et al.  Land use impacts on biodiversity in LCA: a global approach , 2013, The International Journal of Life Cycle Assessment.

[29]  J. Kiviluoma,et al.  The complexity and challenges of determining GHG (greenhouse gas) emissions from grid electricity consumption and conservation in LCA (life cycle assessment) – A methodological review , 2011 .

[30]  Rabbe Thun,et al.  GHG emission performance of various liquid transportation biofuels in Finland in accordance with the EU sustainability criteria , 2013 .

[31]  S. Hoekman,et al.  A review of variability in indirect land use change assessment and modeling in biofuel policy , 2013 .

[32]  Amy E. Landis,et al.  Microalgal biodiesel and the Renewable Fuel Standard's greenhouse gas requirement , 2012 .

[33]  Stephan Pfister,et al.  Review of methods addressing freshwater use in life cycle inventory and impact assessment , 2013, The International Journal of Life Cycle Assessment.

[34]  Erwin Lindeijer,et al.  Biodiversity and life support impacts of land use in LCA , 2000 .

[35]  Helias A. Udo de Haes,et al.  How to approach land use in LCIA or, how to avoid the Cinderella effect? , 2006 .

[36]  T. Koellner,et al.  Principles for life cycle inventories of land use on a global scale , 2013, The International Journal of Life Cycle Assessment.

[37]  Z. Johnson,et al.  Air-water fluxes of N₂O and CH₄ during microalgae (Staurosira sp.) cultivation in an open raceway pond. , 2012, Environmental science & technology.

[38]  M. Huijbregts,et al.  Toward meaningful end points of biodiversity in life cycle assessment. , 2011, Environmental science & technology.

[39]  S. Monni,et al.  Uncertainty in Agricultural CH4 AND N2O Emissions from Finland – Possibilities to Increase Accuracy in Emission Estimates , 2007 .

[40]  Sampo Soimakallio,et al.  How to ensure greenhouse gas emission reductions by increasing the use of biofuels?: Suitability of the European Union sustainability criteria , 2011 .

[41]  C. Bauer,et al.  Key Elements in a Framework for Land Use Impact Assessment Within LCA (11 pp) , 2007 .

[42]  A. Chapagain,et al.  Assessing freshwater use impacts in LCA: Part I—inventory modelling and characterisation factors for the main impact pathways , 2009 .

[43]  Fabiano Ximenes,et al.  A proposal for accounting for biodiversity in life cycle assessment , 2010, Biodiversity and Conservation.

[44]  Llorenç Milà i Canals,et al.  Method for assessing impacts on life support functions (LSF) related to the use of ‘fertile land’ in Life Cycle Assessment (LCA) , 2007 .

[45]  Roberto Dones,et al.  Evaluation of ecological impacts of synthetic natural gas from wood used in current heating and car systems , 2007 .

[46]  Pekka Leskinen,et al.  Social life cycle assessment of biodiesel production at three levels: a literature review and development needs , 2013 .

[47]  Erwin Lindeijer,et al.  Review of land use impact methodologies , 2000 .

[48]  Jesse H. Ausubel,et al.  Peak Farmland and the Prospect for Land Sparing , 2013 .

[49]  Carolien Kroeze,et al.  Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories : Chapter 4. Agriculture , 1997 .

[50]  Eric F. Lambin,et al.  Forest transitions, trade, and the global displacement of land use , 2010, Proceedings of the National Academy of Sciences.

[51]  Roland W. Scholz,et al.  Assessment of Land Use Impacts on the Natural Environment. Part 1: An Analytical Framework for Pure Land Occupation and Land Use Change (8 pp) , 2007 .

[52]  Kaisa Manninen,et al.  Effect of forest-based biofuels production on carbon footprint, Case: Integrated LWC paper mill , 2010 .

[53]  Hayo M.G. van der Werf,et al.  Soil quality in Life Cycle Assessment: Towards development of an indicator , 2012 .

[54]  Vincent Mahieu,et al.  Well-to-wheels analysis of future automotive fuels and powertrains in the european context , 2004 .

[55]  Jessica R. Corman,et al.  Sustainability Challenges of Phosphorus and Food: Solutions from Closing the Human Phosphorus Cycle , 2011 .

[56]  Risto Soukka,et al.  Uncertainty and Sensitivity in the Carbon Footprint of Shopping Bags , 2011 .

[57]  Esa Kurkela,et al.  Process evaluations and design studies in the UCG project 2004-2007 , 2008 .

[58]  Manuele Margni,et al.  A framework for assessing off-stream freshwater use in LCA , 2010 .

[59]  S. Pfister,et al.  Assessing the environmental impacts of freshwater consumption in LCA. , 2009, Environmental science & technology.

[60]  K. L Kadam,et al.  Environmental implications of power generation via coal-microalgae cofiring , 2002 .

[61]  Harro von Blottnitz,et al.  2nd Generation biofuels a sure bet? A life cycle assessment of how things could go wrong , 2011 .

[62]  J. Schröder,et al.  Towards global phosphorus security: a systems framework for phosphorus recovery and reuse options. , 2011, Chemosphere.

[63]  M. Finkbeiner,et al.  The anthropogenic stock extended abiotic depletion potential (AADP) as a new parameterisation to model the depletion of abiotic resources , 2011 .

[64]  M. Thring.  World Energy Outlook , 1977 .

[65]  S. Polasky,et al.  Land Clearing and the Biofuel Carbon Debt , 2008, Science.

[66]  D. Batten,et al.  Life cycle assessment of biodiesel production from microalgae in ponds. , 2011, Bioresource technology.

[67]  Anders Hammer Strømman,et al.  Life cycle assessment of bioenergy systems: state of the art and future challenges. , 2011, Bioresource technology.

[68]  Göran Berndes,et al.  Bioenergy expansion in the EU: Cost-effective climate change mitigation, employment creation and reduced dependency on imported fuels , 2007 .

[69]  Kullapa Soratana,et al.  Evaluating industrial symbiosis and algae cultivation from a life cycle perspective. , 2011, Bioresource technology.

[70]  K. Balāzs,et al.  Modelling soil quality changes in Europe. An impact assessment of land use change on soil quality in Europe , 2011 .

[71]  S. K. Bhatnagar,et al.  Algae-Based Biofuels: a review of challenges and opportunities for developing countries. , 2011 .