Energy use indicators in energy and life cycle assessments of biofuels: review and recommendations

In this study we investigate how indicators for energy use are applied in a set of life cycle assessment (LCA) and energy analysis case studies of biofuels. We found five inherently different types of indicators to describe energy use: (1) fossil energy, (2) secondary energy, (3) cumulative energy demand, (4) net energy balance, and (5) total extracted energy. It was also found that the examined reports and articles, the choice of energy use indicator was seldom motivated or discussed in relation to other energy use indicators. In order to investigate the differences between these indicators, they were applied to a case. The life cycle energy use of palm oil methyl ester was calculated and reported using these five different indicators for energy use, giving considerably different output results. This is in itself not unexpected, but indicates the importance of clearly identifying, describing and motivating the choice of energy use indicator. The indicators can all be useful in specific situations, depending on the goal and scope of the individual study, but the choice of indicators need to be better reported and motivated than what is generally done today.

[1]  Göran Wall,et al.  Exergy conversion in the Japanese society , 1990 .

[2]  Henrikke Baumann,et al.  The hitch hiker's guide to LCA : an orientation in life cycle assessment methodology and application , 2004 .

[3]  Morgan Fröling,et al.  Life cycle assessment of hydrotreated vegetable oil from rape, oil palm and Jatropha , 2011 .

[4]  Wim Turkenburg,et al.  Exploration of the ranges of the global potential of biomass for energy , 2003 .

[5]  G. Murthy,et al.  Life cycle analysis of algae biodiesel , 2010 .

[6]  Detlef P. van Vuuren,et al.  Bio-Energy Use and Low Stabilization Scenarios , 2010 .

[7]  Morgan Fröling,et al.  Assessing the Environmental Impacts of Palm Oil , 2011 .

[8]  Francesco Cherubini,et al.  LCA of a biorefinery concept producing bioethanol, bioenergy, and chemicals from switchgrass , 2010 .

[9]  Gjalt Huppes,et al.  Impact categories for natural resources and land use : survey and analysis of existing and proposed methods in the context of environmental life cycle assessment , 1997 .

[10]  A. Lichtenberg,et al.  Energy and Well-Being. , 1972 .

[11]  Sune Balle Hansen,et al.  Feasibility Study of Performing an Life Cycle Assessment on Crude Palm Oil Production in Malaysia (9 pp) , 2007 .

[12]  M. Huijbregts,et al.  Is cumulative fossil energy demand a useful indicator for the environmental performance of products? , 2006, Environmental science & technology.

[13]  M. Huijbregts,et al.  Cumulative energy demand as predictor for the environmental burden of commodity production. , 2010, Environmental science & technology.

[14]  A. Pizzigallo,et al.  The joint use of LCA and emergy evaluation for the analysis of two Italian wine farms. , 2008, Journal of environmental management.

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

[16]  Sven Bernesson,et al.  LIFE CYCLE ASSESSMENT OF RAPESEED OIL, RAPE METHYL ESTER AND ETHANOL AS FUELS - A COMPARISON BETWEEN LARGE- AND SMALL- SCALE PRODUCTION , 2004 .

[17]  Bruce Hannon Bottles cans energy , 1972 .

[18]  U. K. Rout,et al.  Energy and emissions forecast of China over a long-time horizon , 2011 .

[19]  A. Antón,et al.  LCA of poplar bioenergy system compared with Brassica carinata energy crop and natural gas in regional scenario , 2009 .

[20]  Vaclav Smil,et al.  Energy at the Crossroads: Global Perspectives and Uncertainties , 2005 .

[21]  Peter F. Chapman,et al.  1. Energy costs: a review of methods , 1974 .

[22]  U. Sonesson,et al.  Life cycle assessment of integrated food chains—a Swedish case study of two chicken meals , 2008 .

[23]  Wouter Achten,et al.  Life cycle assessment of a palm oil system with simultaneous production of biodiesel and cooking oil in Cameroon. , 2010, Environmental science & technology.

[24]  Y. Basiron Palm oil production through sustainable plantations , 2007 .

[25]  Clive Ponting,et al.  A New Green History of the World: The Environment and the Collapse of Great Civilizations , 1991 .

[26]  Stefanie Hellweg,et al.  Solar energy demand (SED) of commodity life cycles. , 2011, Environmental science & technology.

[27]  Sven Gärtner,et al.  Rain forest for biodiesel? : Ecological effects of using palm oil as a source of energy , 2007 .

[28]  Jun Zhang,et al.  Emergy analysis of cassava -based fuel ethanol in China , 2010, 2010 The 2nd Conference on Environmental Science and Information Application Technology.

[29]  E. Gnansounou,et al.  Life cycle assessment of soybean-based biodiesel in Argentina for export , 2009 .

[30]  Simone P. Souza,et al.  Greenhouse gas emissions and energy balance of palm oil biofuel , 2010 .

[31]  Rita Puig,et al.  Is it environmentally advantageous to use vegetable oil directly as biofuel instead of converting it to biodiesel , 2011 .

[32]  Christel Cederberg,et al.  System expansion and allocation in life cycle assessment of milk and beef production , 2003 .

[33]  Shabbir H. Gheewala,et al.  Full chain energy analysis of biodiesel production from palm oil in Thailand , 2009 .

[34]  S. Molander,et al.  Life cycle assessment of wastewater systems : Influence of system boundaries and scale on calculated environmental loads , 2000 .

[35]  Kasra Samiei,et al.  Entropy Analysis: A tool for optimal sustainable use of biorefineries , 2010 .

[36]  Gregory M. Bohlmann,et al.  Biodegradable packaging life-cycle assessment , 2004 .

[37]  Xavier Gabarrell,et al.  Exergy analysis applied to biodiesel production , 2007 .

[38]  Reinout Heijungs,et al.  Einstein’ssons for energy accounting in LCA , 1998 .

[39]  Keat Teong Lee,et al.  Life cycle assessment of palm biodiesel: Revealing facts and benefits for sustainability , 2009 .

[40]  Fausto Freire,et al.  Life-cycle studies of biodiesel in Europe: A review addressing the variability of results and modeling issues , 2011 .

[41]  Kritana Prueksakorn,et al.  Full chain energy analysis of biodiesel from Jatropha curcas L. in Thailand. , 2008, Environmental science & technology.

[42]  François Maréchal,et al.  Hydrothermal gasification of waste biomass: process design and life cycle asessment. , 2009, Environmental science & technology.

[43]  M. Hubbert,et al.  Nuclear energy and the fossil fuels , 1956 .

[44]  Gengqiang Pu,et al.  Life cycle inventory and energy analysis of cassava-based Fuel ethanol in China , 2008 .

[45]  T. Buchholz,et al.  Sustainability criteria for bioenergy systems: results from an expert survey , 2009 .