BIOENERGY FOR EUROPE: WHICH ONES FIT BEST?

4 Environmental results:
presentation, discussion and interpretation
In this chapter the following groups of results are presented:
• comparisons between biofuels and fossil fuels investigated on the European level
• comparisons between different biofuels regarding special objectives on the European level
• country specific life cycle comparisons (summary of Chapter 7.1)
• comparisons between the countries for each biofuel (summary of Chapter 7.2)
Before the result discussion, in the following introduction information will be given on various aspects
of the result presentation.
4.1 Introduction
In this chapter the most important definitions documented in the previous chapters are summarised.
Furthermore, presentation criteria, the types of sensitivity analyses carried out and the chosen form of
result presentation will be explained.
4.1.1 Life cycles under study
As explained in Chapter 2, each biofuel investigated was compared to its fossil counterpart by means of
complete life cycle analyses. The biofuels under study and their fossil counterparts are listed below.
Table 4-1 Life cycle comparisons and the countries that investigated them
Life cycle comparison Countries involved
Traditional firewood vs. light oil for residential heating Austria, Italy, Switzerland
Triticale vs. coal for electricity production Austria, Denmark, France, Germany
Miscanthus vs. light oil / natural gas for district heat production Denmark, France, Germany, Netherlands
Willow vs. light oil / natural gas for district heat production Denmark, Germany, Netherlands
Wheat straw vs. light oil / natural gas for district heat produc- Austria, Denmark, France, Germany,
tion
Greece
Biogas from swine excrements vs. natural gas for combined Austria, Denmark, Greece, Italy,
heat and power production
Netherlands, Switzerland
Rape seed oil methyl ester vs. diesel fuel for transportation Austria, Denmark, France, Germany,
Switzerland
Sunflower oil methyl ester vs. diesel fuel for transportation France, Greece, Italy
ETBE from sugar beet vs. MTBE for transportation France, Germany, Netherlands
All intermediate calculations and all result tables regarding the European chains are documented in the
external annex. Further information on this can be found in Annex 7.5.
4.1.2 Impacts under study and presentation criteria
The environmental impact categories that were considered in the analyses were discussed in the Chapters
3.3 and 3.4. They are listed in Table 4-2.
In the presentation of the results the following observations have already been considered: with regard
to the parameter greenhouse effect, the differences in the results for the 100 year and 500 year time
horizon respectively were smaller than their uncertainties. Therefore only the 500-year values are presented
here.
The effect of nitrous oxide is uncertain as explained in Chapter 3.4.2, due to the fact that N2O has
both ozone depletion as well as ozone forming properties and the net effect is not yet scientifically
proven. In the graphs a higher N2O emission is indicated as a disadvantage however.