Summary

Plant oil and biodiesel are alternative fuels based on renewable sources as opposed to fossil fuels. Both paths are available for small scale as well as for industrial applications by using well established and developed technologies. For the production of plant oil there are two processes established: cold pressing process as decentralized plant oil production and a combined process of pressing and extraction in industrial scale. Biodiesel is used as pure fuel for refitted vehicles or mixed with conventional diesel. Biodiesel or fatty acid methyl ester (FAME) will be produced by a catalytic reaction and esterification based on vegetable oils as raw material. As raw materials rape seed oil, soya oil, palm oil as well as cooking oil and fats are used. The physical and chemical characteristics of biodiesel depend on the used raw materials. Biodiesel production can be made discontinuously (batch process) or continuously. The technical periphery of the conversion technology and the raw material provision influence crucially the plant economy and the amount of greenhouse gas emissions. Figure 1 shows the typical and default values of the EU directives for vehicle fuel options. Besides the value of biodiesel based on used oil and fats, the GHG-value of plant oil is less than 50% lower compared to fossil conventional fossil fuels (diesel/petrol) (see Figure 1).

Figure 1.: Greenhouse gas emissions (GHG) of rapeseed oil and biodiesel according to EU*

Optimizing potentials in conversion technologies should be further activated to reach the decrease of GHG-emissions by 35 % (54,5 g CO₂equivalent) and 50% (41,9 g CO₂equivalent) from 2017 compared to fossil fuels.

* Source: European Parliament and Council of the European Union: Directive 2009/28/EC on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC

Full document