Short communication. Evaluation of the energy requirements in tractor-disc harrow systems

Abstract

Soil working operations in traditional farming systems involving the use of tractors are among the operations which incur the highest energy costs. The sustainability of such systems requires strictly-controlled resource management leading to a significant reduction in cropproduction costs deriving from savings in fuel consumption.The overall energy efficiency is the ratio of the energy transferred from the tractor to operate the implement, to the energy equivalent to the fuel consumption required to perform the operation.The overall energy efficiency depends on a range of performance factors namely, engine, power transmission and the interaction of tyres with the soil. This last factor implies the definitive influence of soil as a major factor in overall energy efficiency. This is the reason why different authors (Bowers, 1985;Riethmuller, 1989;Smith, 1993), are cautious about the domain of application of their results.The Tractor Performance Monitor (TPM) is increasingly being supplied as standard tractor electronic equipment, or as a factory-fitted option. They provide information to assist tractor drivers and farm managers. The TPM is also an excellent base to perform experiments under real working conditions gathering data that can be used to validate the importance of the different AbstractA three years research project was developed to study tractor-implement dynamics in tillage operations. This paper reports the results of field tests performed under real working conditions, using four wheel drive tractors and trailed disc harrows combinations, under different soils conditions. The data show a linear relationship between the drawbar pull per unit of implement width and the fuel consumption per hectare. The results give evidence of the benefits of the «gear up, throttle down» approach.