Methane/Gasoline Bi-fuel Engines as a Power Source for Standard Agriculture Tractors: Development and Testing Activities

Abstract

Abstract. Promoting energy efficiency in agriculture means supporting economic growth by reducing both pollution and greenhouse gas (GHG) emissions while minimizing waste and the inefficient use of natural resources. Biomethane presents an interesting option given its possibility to be produced from livestock waste or other organic residues, with GHG emission savings ranging from 84% to 86% (wet or dry manure). Moreover, experiences with methane-fueled engines are widely available, thus leading to considering the possibility of using such a fuel in the agricultural sector as well. The aim of this research was to develop a first-generation tractor prototype provided with a commercially available bi-fuel engine adapted for the purpose and tested both in laboratory and field conditions. The main design aspects are depicted while the performance results show similar values of engine power and torque (87 kW maximum power for the diesel fuel tractor and 88 kW for the methane-fueled version; 1172 Nm maximum torque at 550 min-1 for the methane and 1155 Nm at 400 min-1 for the diesel tractor) with an autonomy of the methane prototype which is, at present, 40% of a comparable standard tractor. The possible role in farm fleet is also presented. Keywords: Agricultural machinery, CNG, Gaseous bio-fuels, Renewable fuels.