internship thesis by Alain ZANARDO. Agro Industrial transformations 2005-2006. University Department of Agen.
Keywords: biofuel, yield, production, comparisons, costs, inputs, fertilizers, flow, impact, CO2, energy balance.
The study of cropping inputs from an energy point of view is the subject of this memoir.
"Energy assessment of inputs and agricultural and forestry production. "
Alternatives to these inputs and their effects on the yields of energy crops will be addressed; The societal aspect focuses on the peasant world will be underlying.
Energy assessment of 15 crop inputs for sunflower and maize.
Creating an energy equivalency bank for each input for calculating the energy efficiency of crops.
Application for energy crops:
1) Direct combustion seeds
2) Pure vegetable oil
3) oils Esters
4) Ethanol Fuel
Paralleling ethanol production the USA and France.
This study was born from the virtual meeting with two scientists, one in 1990 at the time of the publication of his works on large crop productions (1972 dice), the other in 2005 at the publication of his study on alcohol USA indicating energy efficiency lower than 1. A height for energy production.
The reading of the works of Dominique Soltner (DS) 17th edition of 1990 page 6 shows that he knew the works of David Pimentel (DP) quoted by Joel de Rosnay in Research 47 July-August 1974: "Agricultural production: a deteriorating energy balance ". In the 2005 edition there is no longer any reference to DP jobs.
The work of DP was controversial in January 2006 by Alexander Farrell (AF) who shows that the production of fuel ethanol has a yield of 1,2 when the energy of the co-products is counted: DDGS-CGF-CGM.
In 2002 the ADEME reports a study on this subject with a yield superior to 2.
In December 2005 INRA recounts the correction of the ADEME figures by the IPCC and we find 1,18 for wheat ethanol and 1,28 for beet ethanol.
In March 2005 an evaluation of the externalities of the bioethanol corn sector in France by ECOBILAN results in an energy efficiency of 1,35 or 1,88.
Finally in February 2006, a billion euros will be injected by the French state in this sector so controversial by scientists.
The low energy efficiency of ethanol production from agricultural production is beyond doubt. What is doubtful is the close dependence of this output on the energy inputs used for these productions. Undervaluation or omission may be fatal to this performance; this is written by DS (in 1990) and DP (in 2005). The same is true for any overvaluation of average yields of crops and transformation into final energy.
Limitations of the study:
Industrial transformations are not studied nor greenhouse gases.
The quantifications of each input depend on the authors; they are often distant: the arbitrations attempted in this memoir can not be definitive; when will a Hand Book on inputs and agricultural production?