Life cycle analyses applied to first generation biofuels used in France

Feb 2010

Aside from questions of economics (tensions on agricultural markets) and ethical issues (good agricultural resource use), biofuels are accused of not delivering the advantageous balances imputed to them early on, in terms of reducing greenhouse gas emissions and fossil resources consumption. Indeed, to produce biofuels requires consuming fossil resources, whether directly via agricultural machinery and via transforming agricultural matter into fuel, but also in non negligible quantity for producing fertilizers and other inputs.
In order to try addressing such objection, one should seek to objectify the debate. This can be achieved by using a life cycle analysis of fossil fuels and biofuels products, in order to compare both channels and hence determining the level of greenhouse gas emission reduction of one in relation to the other. Such work is complex, and calculation hypotheses influence the outcome non negligibly.
The study of life cycle analyses (LCA) applied to first generation biofuels used in France provides not only an actualization as complete as possible of biofuels energy balances and greenhouse gas emissions, but also an evaluation of three new impact indicators (eutrophication potential, photo-oxidization, human toxicity). It has led to methodological choices, but strictest scrupulousness was sought-after and applied to ensure that such choices were not arbitrary. Simulation and calculation steps were clarified and a large place was let for opposition, in light of the current state of scientific knowledge.
The existence of indirect effects on the markets adds to this complexity. That given, it became necessary to set up appropriate legislative frameworks, seeking to limit environmental risks (see box at the end of this chapter). So the "Grenelle environment Round Table" recommended completing an exhaustive and adversary evaluation of the impacts of biofuels consumed in France. A first study was conducted in 2007-2008 aiming at determining the methodology for biofuel life cycle assessment (LCA) based on comparing various studies conducted in the world on this subject. All parties concerned by biofuel development were associated for conducting the study: representatives from agricultural institutes, petroleum, and automobile industries, and environmental associations. The writing of a methodological guide concluded this work, defining recommendations for performing LCAs for biofuels consumed in France.
This document provides a synthetic version of the results presented in the full report. In order to clarify the analysis of the results, the main methodological choices as well as their main limits will be recalled first.

By: Bio Intelligence Service

 
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