5 years ago



14 2 Biofuels under

14 2 Biofuels under study The results of previous projects and reports were also taken into consideration in order to find the most adequate sources of biofuel to be assessed in each country. The results of these considerations are given in Table 2-1. The various assessments carried out within each country were then combined in order to obtain average results for the European scenario. These are presented in the Chapters 4.2 and 4.3. The results for each individual country are found in Chapter 7.1 in the Annex. A summary is given in Chapter 4.4. The comparisons between the biofuels and the fossil fuels depend partly on the intended use of the respective fuel. Thus whether a particular biofuel is compared to diesel fuel, light oil, hard coal or natural gas depends partly on whether it is to be used for transport, for producing heat or electricity. The nine biofuels were compared to the particular fossil fuels listed in Table 2-2. Table 2-2 Investigated biofuels, their utilisation and fossil counterparts Biofuel Utilisation Fossil fuel Triticale Co-firing for electricity Hard coal Willow District heating Light oil and natural gas Miscanthus District heating Light oil and natural gas Rape seed oil methyl ester (RME) Transport Fossil diesel fuel Sunflower oil methyl ester (SME) Transport Fossil diesel fuel ETBE from sugar beet Transport MTBE Traditional firewood Residential heating Light oil and natural gas Wheat straw District heating Light oil and natural gas Biogas from swine excrements Heat and electricity Natural gas Hemp Gasification for electricity Hard coal The investigated chains differ with regard to the type of energy (i. e. heat, electricity, transportation) and the level of technological development. For space heating, different sources of renewable energy are available, bioenergy being one of them. For electricity generation, high quality fuels and/or expensive technologies are required. The firewood chain is well established on the market. The technology for ETBE from biomass as an additive for gasoline is already relatively mature and the change from MTBE to ETBE is a feasible one. Due to the high iodine number the car industry avoids the use of sunflower oil methyl ester. Biogas from swine excrements for heat and power is on its way to market establishment. For heat production, willow has reached the pilot stage and wheat straw the slightly more advanced demonstration phase. No proven technology is available for heat from Miscanthus, but this can be expected by 2010. Electricity from triticale and hemp has not been produced yet and the development seems to be uncertain, as the same slagging and corrosion problems can be expected as is the case with straw. 2.2 Principles of the biofuel-fossil fuel comparisons The comparisons between the various biofuels and their respective fossil counterparts were based on the principle of life cycle assessment (LCA). This involves an assessment of the environmental effects associated with the production as well as utilisation and/or disposal of a certain product. All processes involved are taken into consideration, i. e. “from cradle to grave”. With regard to biofuels from agricultural crops for example this includes the manufacture and application of fertiliser and pesticides, the fuel used in tractors and so on, through to processing and the combustion of the fuel. All these effects are then compared to those arising from the use of fossil fuels. This is done with regard to a number of environmental parameters such as greenhouse gas emissions, acidification, etc. Figure 2-1 is an example of a schematic life cycle comparison between a biofuel and a fossil fuel. A more detailed description of the parameters involved, the methodology applied and other criteria used within an LCA is given in Chapter 3. For every biofuel, the whole life cycle was analysed to a high degree of differentiation and in accordance with the ISO 14040 ff. standards. Likewise, the life cycles of the fossil fuels were investigated in detail. An example of a life cycle comparison showing the full details considered within the calculations in this project (e. g. how the system boundaries were chosen etc.) can be found in Chapter 3. Pro-

2.2 Principles of the biofuel-fossil fuel comparisons 15 viding this information for all the life cycles investigated within this project would exceed the scope and the objective of this report, but the source for detailed information can be found in Annex 7.5. In this chapter, simplified representations are given of all the biofuel life cycles investigated in this project. In the following sections the biofuel life cycles are described. They are grouped according to the nature of the production line of the fuels, i. e. whether they stem from solid cultivated raw materials such as Miscanthus, or liquid ones like rape seed oil, or else from residual materials from agriculture or forestry. Finally, the novel production line of hemp is given in a separate section. In all of these life cycle comparisons, the fossil fuels are represented on the left hand side of the diagram. On the right hand side the reference system is given. The reference system defines the indirect effects of the bioenergy production system, which are not covered by the comparison with the fossil fuel directly, such as the use of non-energetic co-products like fodder, which contribute to save conventional resources. It also defines what the land area that is used for biofuel production would be used for in the case of fossil fuel utilisation, i. e. an alternative land use. In this project it is generally taken to be fallow land, because this is considered to be the simplest and most realistic reference system. Furthermore, where relevant, additional environmental “credits” are indicated, which arise from any co-products and result in the potential saving of conventional resources and the effects of their utilisation. Fossil fuel production system Resource extraction Fossil fuel Raw material production Transport Processing Transport Combustion Comparison Bioenergy production system Pesti- cides Fuel Agriculture Biofuel Fertil- iser Environmental credits for the biofuel Fallow maintenance Co-products Figure 2-1 Simplified representation of a life cycle comparison between a fossil fuel and a biofuel

Bioenergy Update 10-02 - General*Bioenergy
Maximising the environmental benefits of Europe's bioenergy potential
Desktop Management Tools — Which One Is the Best?
Choose The One That Best Fits Your Lifestyle! - Java Fundraiser