In 2003, the European Parliament and the EU Council adopted the Directive on the promotion of the use of biofuels and other renewable fuels for transport (no. 2003/30/EC), introducing measures for such incentives to replace the use of diesel fuel and gasoline in transport. This presents an important contribution to the realisation of objectives to improve the reliability of energy supply, reduce GHG emissions and create new possibilities of sustainable rural development. The Directive has set requirements that EU Member States provide a minimum share of biofuels and other renewable fuels in transport, and for this purpose, with regard to the marketing of fuels, determine their state target values of shares of biofuels for their areas. For EU Member States, referential values for the state target values of shares of biofuels in transport have also been set - 2 % by the end of 2005 and 5.75 % by the end of 2010.

Despite the optimistic forecasts on the positive effects of biofuels, doubts on their use have been increasing lately. Especially the production and use of the first generation of biofuels (agrofuels) is disputable; namely, the latter might have negative impacts on biological diversity, water and soil protection, global changes in land use, an increase in the prices of food, etc. Therefore, attention is slowly being redirected to the second generation of biofuels (waste, plant residues, such as wood biomass, straw, grass, etc.), which is still poorly researched and for which production is also expensive (EEA, 2008). Considering the high prices of engine fuels and our increasing energy dependence, the EU has high hopes for biofuels, which would, together with other renewable energy sources, by 2020 represent 10 % of the energy mix (EEA, 2009).

The EU Directive introduces significant changes regarding alternative fuels in Slovenia, since it lead to the adoption of a legislative basis and financial incentives, which present a solid basis for the implementation of measures for the promotion of the use of such fuels:
- Operational Programme for Limiting Greenhouse Gas Emissions, the amendments of which were adopted by the Government of the Republic of Slovenia in 2006, representing the starting programme document of the Republic of Slovenia for the introduction of measures for the promotion of the use of biofuels in transport (MESP, 2006).
- Excise Duty Act (OG RS, no. 02/2007), which stipulates that biofuels shall not be subject to excise control and the payment of excise duties, if used as engine fuels in their pure form. If mixed with fossil fuels, the exemption from the payment of excise duties can be claimed up to a maximum of 5 %.
- Decree on the promotion of the use of biofuels and other renewable fuels for the propulsion of motor vehicles (OG RS, no. 103/2007), which in accordance with the EU Directive no. 2003/30/EC stipulates: the types of biofuels used in transport, and the shares of annual amounts of biofuels marketed in the Republic of Slovenia for the propulsion of motor vehicles. In accordance with the provisions of Articles 5 and 6 of this Decree, distributors of fuels for the propulsion of motor vehicles in transport must ensure that the annual average content of marketed biofuels in all fuels for the propulsion of motor vehicles in Slovenia is equal to at least 2 % in 2007, at least 3 % in 2008, at least 4 % in 2009, at least 5 % in 2010, at least 5,5 % in 2011, at least 6 % in 2012, at least 6,5 % in 2013, at least 7 % in 2014 and at least 7,5 % in 2015.

The estimated shares of biofuel consumption are not achieving the referential shares referred to in the indicated Directive, since in Slovenia there are no refineries for the production of motor gasoline; biofuels appropriate for mixing with motor gasoline are not produced either. Biofuels in the Republic of Slovenia were experimentally mixed into diesel fuel intended for the propulsion of motor vehicles in road transport already in 2004. The added biodiesel in diesel fuels was partly imported from third countries, obtained from other EU Member States and partly also produced in Slovenian plants for the production of vegetable oil (MESP, 2005).

In Slovenia, the best technological possibilities exist for the production of biodiesel or pure (raw) vegetable oil as an alternative engine fuel. The basic raw material for them is oil, obtained by the cold pressing of oilseed rape or sunflower. For the final obtainment of biodiesel, a further procedure of vegetable oil estherification is necessary; for this procedure the raw material, produced on Slovenian agricultural land or imported, will be used. In the future, the majority of the planned production of biodiesel will be based on imported raw materials, since according to the estimates of the Ministry of Agriculture, Forestry and Food only a maximum of 6.000 to 7.000 hectares of land in Slovenia would be appropriate for the production of oilseed rape (MESP, 2009).