Changes, challenges and opportunities in the wood energy supply chain
Seinäjoki University of Applied Sciences, School of Agriculture and Forestry,Ilmajoentie ⁵²⁵, ⁶0⁸00 Ilmajoki, Finland;
e-mail: antti.pasila@seamk.fi
Abstract:
One of the biggest challenges in using bioenergy has been the problem of logistics;that is how, in many cases, to process and transport these low density and bulky raw materials.Finnish forestry technology is advanced and the same machinery which is used in timberharvesting is often used in energy wood harvesting.A change in the forest industry has however caused some new expectations concerning thewood energy supply chain. One of the basic requirements for woodchips is low moisturecontent. In the transportation of wood chips high moisture content, and therefore a high weight,may limit the carrying capacity of vehicles and roads. Also in syngas and charcoal productiondry raw material is needed to be able to control the combustion process.The reduction of moisture content under natural drying conditions means an extended storagetime. With Finnish climate conditions this normally means a storage period of at least one year.The various types of energy wood: stems, whole tree harvested stems, logging residues orstumps are piled in storage sites and covered. The raw material is chipped or crushed at theseintermediate storage sites and after that transported to bio-refineries.In the measurement of the energy wood’s quality and quantity there are some differencescompared to timber measurements. Normally the timber measurements are based on solidvolume in cubic metres. The forest harvesters are equipped with on-line measurement systems.This on-line measurement is more complicated to carry out in the case of energy wood.Especially difficult are the volume measurements in whole tree and stump harvesting. A newmethod used in the measurement of energy wood is weight.
Key words:
drying, logistics, moisture content., transport, weight measurements, Wood energy