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76 4 Environmental

76 4 Environmental results: presentation, discussion and interpretation 4.4.8 Switzerland In the result table below there is an overview of the advantages and disadvantages from the biofuels compared to their fossil counterparts. The scheme for determining and assessing the significance of the results for each impact category was published in Wolfensberger and Dinkel (1997). Impact category RME Firewood vs. light oil Firewood vs. nat. gas Biogas Use of fossil fuels Very favourable Very favourable Very favourable Very favourable Greenhouse effect Favourable Very favourable Very favourable Very favourable Acidification Unfavourable Comparable Unfavourable Unfavourable Eutrophication Favourable Unfavourable Unfavourable Comparable Human toxicity Comparable Favourable Very unfavourable Unfavourable Summer smog Comparable Favourable Unfavourable Favourable Regarding the major reasons of the authorities for promoting biofuels (saving of fossil fuels and reduction of global warming), all three investigated biofuels are highly recommendable. But one has to be aware of the fact that for biogas these advantages have to be partly paid with higher potentials in acidification and human toxicity. Moreover, the outcome for RME, which is more favourable as it was the case in previous studies (the results are unfavourable here only for acidification), partly depends on the procedure applied for taking into account the contribution of rape seed meal (this comment is valid first of all for eutrophication and the use of fossil fuels). Research is needed concerning the real relevance of these negative environmental aspects in the whole assessment. The results indicate that the probably best biofuel is wood compared to oil heating, because there only the impact potential eutrophication is unfavourable and the result does not depend on a methodological choice.

4.5 Summary of comparisons between the countries for each biofuel 77 4.5 Summary of comparisons between the countries for each biofuel This chapter is a summary of the results presented in Chapter 7.2 in the Annex, where the environmental effects of all biofuels are compared between the various countries that investigated them. Table 4-4 lists the comparisons carried out in this context: Table 4-4 Life cycle comparisons and the countries that investigated them Life cycle comparison Countries involved Traditional firewood vs. light oil Austria, Italy, Switzerland Triticale vs. coal Austria, Denmark, France, Germany Miscanthus vs. light oil / natural gas Denmark, France, Germany, Netherlands Willow vs. light oil / natural gas Denmark, Germany, Netherlands Wheat straw vs. light oil / natural gas Austria, Denmark, France, Germany, Greece Biogas from swine excrements vs. natural gas Austria, Denmark, Greece, Italy, Netherlands, Switzerland Rape seed oil methyl ester vs. diesel fuel Austria, Denmark, France, Germany, Switzerland Sunflower oil methyl ester vs. diesel fuel France, Greece, Italy ETBE from sugar beet vs. MTBE France, Germany, Netherlands The results reflect differences in production and conversion methods within the various countries, leading to differences in the environmental performance of the different fuels. This comparison enables an assessment of where within Europe it might be most efficient to produce any of the biofuels considered here. All country representatives were responsible for the input data of their respective country. Differences in yields also influence the results of the environmental analysis. The differences between countries are most profound with the perennial crops, which may be explained by differences in the scarce experiences with these crops and their cultivation. The influence of this variation in yields on the results is limited however, if GJ primary energy is used as functional unit. The influence is larger when the analysis focuses at efficiency of land use. The results give a very heterogeneous picture: for certain biofuels and impact categories the differences between the countries are relatively small, while for others they are significantly large. The magnitude of the differences appears to be more dependent on the biofuel than the impact categories, thus for some chains, such as wheat straw, the values for all countries and with respect to most impact categories lie relatively closely about the European average, while for other chains, e.g. biogas, the values differ significantly. It is noticeable that with the exception of biogas for all biofuels the parameters use of fossil fuels, greenhouse effect and human toxicity show very similar results between the countries, while for the other categories the differences tend to be larger.

Bioenergy Update 10-02 - General*Bioenergy