While legal restrictions on the use of fossil fuels are being applied to conserve natural resources, mixed spirit fuels, vegetable oils and their esters are attracting increasing attention as promising alternative sustainable energy sources for tractors and agricultural machinery. The paper substantiates the need for the use of biofuels in tractor diesel engines. It is shown that the choice for diesel alternative biofuel with a perspective should be carried out in accordance with the design features of the engine and during its primary tests. In the paper we investigate such environmentally friendly energy sources such as methanol, ethanol and methyl ester of rapeseed oil (MЕRО). Methanol, ethanol and MЕRО have the potential to lead to some solutions to environmental problems, as there are abundant resources for their production and these sources of energy are characterized by relatively low emissions of harmful substances during combustion. The ways of bioethanol production from various raw materials and the process of rapeseed oil methanolysis are considered. It is shown that agricultural enterprises that consume mainly petroleum products as fuel are now quite capable of producing at least environmentally friendly renewable biofuels for their tractors. Experimental studies of tractor diesel engines on biofuels of the following compositions were carried out: alcohol-fuel emulsion (AFE, alcohol (methanol, ethanol) - 25 %, detergent-dispersing additive succinimide C-5A - 0,5 %, water - 7,0 %, diesel fuel - 67,5 %); methanol (88,0 %) and MЕRО (12,0 %). Based on the studies of the thermal performance of tractor diesel engines running on biofuel, the nature of the influence of their work on the characteristics of heat dissipation and defined their numeric values.