The energy consumption and economic costs of different vehicles used in transporting woodchips

Abstract

One of the weak points in the energy-wood chain is the transport of woodchips from the forestry yard to the power station. This operation is critical because the vehicles used must be very versatile to operate under different conditions while maintaining low operating costs. The goal of this study is to implement the information on this topic by examining the different categories of vehicles that are considered to be appropriate for this purpose. For each category of vehicle, the working time, working rate, fuel consumption, energy costs and economic costs were processed.Tests were conducted using both “agricultural convoys” (tractor+trailer) and “industrial vehicles” (lorries).All vehicles were tested on short itineraries of approximately 5, 15 and 25km and on long itineraries of 50, 100 and 200km.The study showed that on routes longer than 25km, lorries had the highest average transfer speed (42kmh−1) whereas agricultural vehicles had the lowest (24kmh−1).The transport costs depending on the distance, the type of vehicle used and the unit cost (€km−1) were high, especially for distances less than 20km (up to 5€km−1).The application of these values to a biomass-fed thermal power unit of 1MW with an annual use of 2000h and a supply of biofuels in the radius of 75km shows that 1500hyear−1 are needed for the bestowal of chips to power the unit (3700tss). The total cost for a lorry is approximately € 148,000year−1 and approximately four times higher for agricultural convoys.The energy required to transport the woodchips is approximately 90MJm−3 loose chips for agricultural vehicles and 35MJm−3 loose chips for lorries. In both cases, these values represent a small claim (2%) of the energy value of the biomass transported.