Evaluation of John Deere 1490D operation phase in typical conditions of the Czech Republic

The life cycle operation phase of John Deere 1490D energy wood harvester from the aspect of energy audit and environmentally negative influence caused by emissions were evaluated. Energy audit quantifies energy used in the form of fuels and oils as well as energy expended for manufacture, transport and distribution of these fuels and oils. Emissions produced by operation are determined according to the consumption of fuels and oils based on emission factors. We also made a comparison of the general calculation of costs based on data provided by the manufacturer with costs ascertained in real operating conditions. The costs are divided into purchase, operating and other costs. Total costs are subsequently converted into unit costs according to the assumed productivity of the machine, its estimated lifetime, and the mean real throughput of the machine. The machine throughput, and thus also its operating econom - ics, is greatly dependent on the character of the processed material, its stem volume, moisture, way of dendromass preparation, and operator's skills. Energy use was calculated at 74.4 MJ·FU -1 (functional unit) related to fuel consump- tion and 13.4 MJ·FU -1 related to the consumption of oils. The total energy use of the life cycle operation phase of the slash bundler was determined as 87.8 MJ per each bundle produced. The real productivity of the machine in the given operating conditions was several times lower than the productivity indicated by the manufacturer.