Presently, vegetable oil is regarded as a niche application. One liter of rapeseed oil substitutes for approximately 0.96 L of diesel. The annual yield is 1480 L/ha. CO2 reduction in relation to the diesel equivalent is about 80% [36]. However, this is questioned in newer literature [33] in terms of global warming reduction considering the effects of extra N2O entering the atmosphere as a result of using nitrogen-based fer­tilizers to produce crops for biofuels. Before unmodified vegetable oil is used as a fuel, the engine must be refitted for the fuel to correspond to the viscosity and combustion properties of vegetable oil. Refitting concepts include preheating either the fuel and the injection system or the equipment with a two-tank system. The engine is started with diesel and changes to vegetable oil only when the operating tempera­ture has been reached. Blends of pure vegetable oils and a conversion product together with additives (antioxidants) increase oxidation sta­bility, reduce viscosity, and give a better perspective for vegetable oil fuel markets.