Productivity and cost of biofuel in ditch cleaning operations using tracked excavator based harvester
¹Latvian State forest Research Institute 'Silava', RPgas street 111, LV-2169 Salaspils,
²Forest Sector Competence Center, DzRrbenes street 27, LV-1006 RPga, Latvia
Forest ditches is one of the poorly utilized sources of biomass for energy production and timber industry. Increase of productivity and reduction of cost of extraction of biomass from the ditches, retaining at the same time high quality standards, are the key issues of mechanization of harvesting operations in this area. The scope of the study was to evaluate productivity and cost of biomass delivered from forest ditches, when tracked excavator based harvester and different work methods are used. New Holland 215B excavator with Ponsse H7 felling head was used in trials. The machine was operated by experienced operators. The study was implemented in drainage systems managed by Joint stock company „Latvia state forests”. Total extracted area 12 ha, extracted biomass – 734 m3. Duration of the study including harvesting and forwarding – 4 months. Average cost of roundwood production including road transport to 50 km distance in the trials was 27 EUR m-3, average cost of biofuel – 11 EUR m-3 (4.5 EUR LV m-3). The study approved advantages of excavators in ditch cleaning operations; however, several improvements are possible. The machine should be equipped with smaller accumulating felling head, delimbing and bucking should be done in parallel to a ditch direction, number of assortments should be reduced, as well as extraction of trees with diameter below 6 cm should be avoided.