CO2 emissions and energy consumption of loaders in woodchip loading operation

Woodchip is the most widespread form of wood biomass used in power stations because it guarantees homogeneous sizes and high load densities. From an environmental point of view, woodchip production has been studied from many aspects (comminution wood, transportation.), but no experimentations have focused on loading operations. The goal of this work was to evaluate the energy consumption and CO2 emissions of four types of loader used in woodchip loading. A knuckle-boom loader and three front loaders were tested. In the trials, a different woodchip pile position (near a wall and in an open square) was considered. Higher values on energy consumption were obtained by a mechanical shovel equipped with a standard bucket (5.59 and 5.01 MJm(-3), for woodchip stored in piles sited near a wall and in an open square, respectively), whereas lower values were observed during the use of telescopic loaders (1.89 and 2.09 MJm(-3), for piles sited in an open square and near a wall, respectively). The same results were also observed for CO2 emissions, where the best performances were obtained by the telescopic handler (58.6 kg h(-1)), with the worst by the mechanical shovel (118.4 kg h(-1)). The study pointed out that in woodchip loading, telescopic handlers equipped with a hinged bucket are able to reach a higher working efficiency with lower energy consumption and CO2 emissions in all working conditions.