Abstract

The biomass of forests is one of the oldest and most popular sources of renewable energy. Aside from round wood, logging residue is also being used with increasing frequency to produce energy. Under European conditions, the most frequently implemented technology of using logging residue is chipping, either directly at the cutting site or at the forest roadside. However, for over a dozen years now, with more and more success, solutions have been implemented which make it possible to compress the biomass into bundles. The aim of this study was to estimate the work efficiency of a John Deere 1490 bundler working in clear cuts with various degrees of material preparation. The structure of a working day, work productivity rates, as well as cost and energy consumption were determined for each of three variants. The effectiveness of using a bundler, expressed by the productivity achieved, depends largely on the extent the wood slash is prepared. When the slash is concentrated in rows or piles, the machine does not have to travel over the entire work area to gather scattered material, which increases work efficiency by about 25 to 30%. The obtained values relevantly affected costs and the amounts of energy consumed.

Key words: Renewable energy, forest biomass, slash bundler, time study, energy use.