Relative to fossil fuels, sustainably produced biofuels result in a reduction in carbon dioxide emissions across their lifecycle. Carbon dioxide absorbed by plants during the growth of the biomass is roughly equivalent to the amount of carbon produced when the fuel is burned in a combustion engine, which is simply

Second Generation Biofuels and Biomass: Essential Guide for Investors, Scientists and Decision Makers, First Edition. Roland A. Jansen. r 2013 Wiley-VCH Verlag GmbH & Co. KGaA.

Published 2013 by Wiley-VCH Verlag GmbH & Co. KGaA.

returning the carbon dioxide to the atmosphere. This would allow the biofuel to be approximately carbon-neutral over its lifecycle. However, there are emissions pro­duced during the production of biofuels, from the equipment needed to grow the crop, transport the raw goods, refine the fuel, and so on. When these elements are accounted for, biofuels are still anticipated to provide an estimated 80% reduction in overall carbon dioxide lifecycle emissions compared to fossil fuels. For example, analysis of Camelina feedstock use for aviation has shown even better results, with an 84% reduction in lifecycle emissions. Furthermore, biofuels contain fewer impurities (such as sulfur), which enables an even greater reduction in sulfur dioxide and soot emissions than present technology has achieved.

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