volume: 47, issue: 2
A substantial percentage of global timber grows on challenging and steep terrain. This resource can be accessed with cable yarders or traction-assisted forwarders. When choosing which harvesting solution to employ for a particular logging job, its energy efficiency should also be considered, given the ever-rising energy cost. This theoretical study develops analytical models to determine and compare the fuel consumption of a cable yarder and a traction-assisted forwarder used for uphill extraction. Simulation results indicate that forwarding requires on average 69% more fuel per unit of transported payload across a range of work conditions (e.g. distance, slope gradient, payload size) and at least 47% more fuel under all simulated conditions. The efficiency advantage of cable yarding could be boosted further by transporting heavier loads. In cable yarding, a significant portion of fuel is consumed during standstill, when the engine runs idle or at low efficiency for extended periods of time. In forwarding, loading and unloading are particularly energy intensive. While cable yarders could greatly benefit from electrification, forwarders may see lower efficiency gains due to the challenges in electrifying linear hydraulic actuators in a cost-effective and robust manner.
volume: issue, issue:
A substantial percentage of global timber grows on challenging and steep terrain. This resource can be accessed with cable yarders or traction-assisted forwarders. When choosing which harvesting solution to employ for a particular logging job, its energy efficiency should also be considered, given the ever-rising energy cost. This theoretical study develops analytical models to determine and compare the fuel consumption of a cable yarder and a traction-assisted forwarder used for uphill extraction. Simulation results indicate that forwarding requires on average 69% more fuel per unit of transported payload across a range of work conditions (e.g. distance, slope gradient, payload size) and at least 47% more fuel under all simulated conditions. The efficiency advantage of cable yarding could be boosted further by transporting heavier loads. In cable yarding, a significant portion of fuel is consumed during standstill, when the engine runs idle or at low efficiency for extended periods of time. In forwarding, loading and unloading are particularly energy intensive. While cable yarders could greatly benefit from electrification, forwarders may see lower efficiency gains due to the challenges in electrifying linear hydraulic actuators in a cost-effective and robust manner.
