Analysis of energy wood supply chain in thinning operations: a case study in a pine stand of Central Italy

Abstract

Thinning is an essential practice in Mediterranean pine forests management but is rarely applied because of the high harvesting costs. The new market of bioenergy products could give a profit to wood biomass harvesting activities, though the drawbacks of elevated supply chain costs, related to technical problems and lack of knowledge about the wood quality have to be overcome in advance. This study analyzed technical, economic, energy and environmental factors of a pine stand thinning in Central Italy, where collected biomass was directed to energy, in order to give a decisional support to reach economical profitability and environmental sustainability in thinning practices. The introduction of Full Tree System maximized the recovery of available biomass, full tree chipping produced material with Heating Value superior than single tree components. The use of a felling frame in motor-manual felling in comparison with the traditional chainsaw reduced operator effort, increasing the number of felled trees per hour, when the stump diameter remained under 15 cm. The energy wood supply chain is not sustainable from an economic point of view, the profitability could be reached only acting on suggested technical levers and particularly reducing costs of hauling operation. The estimation of output/input energy ratio in the supply chain underlined the feasibility of thinning practices for energy. The assessment of CO2 emissions confirmed the environmental sustainability of biomass supply chain in energy when compared to traditional fossil fuels. Study conclusions provide the guidelines for thinning treatment in Mediterranean pine stands, in order to reach environmental and economic sustainability of these practices

Life Cycle Assessment of Wood Chips from Residual Biomass: A Case Study

“…Residual biomass of forest origin is collected in the forest using a tractor and a winch (a machine used in forestry sites to move plant masses placed in positions that cannot be reached by self-propelled vehicles) (Figure 3). With reference to the indirect drag of the residual biomass (use of the tractor equipped with a winch), a productivity of 1.35 t/h was calculated for the tractor equipped with a forestry winch [13], while and an average consumption of 4.6 l/h of diesel as fuel was estimated [14] (Table 3).…”

“…Figure 3. Forestry tractor with a winch The methods of collection and drag are: -Indirect drag: the tractor remains stationary and the wood collection is carried out by means of the winch; -Direct drag: an activity in which the load (biomass) moves together with the towing vehicle (tractor and winch).With reference to the indirect drag of the residual biomass (use of the tractor equipped with a winch), a productivity of 1.35 t/h was calculated for the tractor equipped with a forestry winch[13], while and an average consumption of 4.6 l/h of diesel as fuel was estimated[14] (Table3).In order to examine the movement of the biomass to the storage site (direct drag), an average drag distance of 1 km was assumed[15].…”

Analisi della filiera foresta-legno in una prospettiva di (bio)economia circolare: il caso studio della foresta di Monte Morello

“…Verani et al (2017) stimano per la fase di abbattimento con motosega in piantagioni artificiali di conifere una produttività media di 1,2-1,6 t h -1 , mentre per l'esbosco effettuato con trattore munito di verricello sono state calcolate produttività comprese tra 2,9 e 3,8 t h -1 per operaio. Baldini et al (2010) hanno calcolato una produttività di 3,2 t h -1 per l'abbattimento in pinete mediterranee di 35 anni e 1,35 t h -1 per l'esbosco eseguito con Same Explorer 80 da 60 kW munito di verricello forestale.…”