Forest15.04.2010

Energy can be transformed into currency

Branch and sticks are good sources of energy

Branch and sticks are good sources of energy 

A thicket, trunks, stubs and branches…Plenty of wood that is easily considered useless. Energy logging is not something to be underrated, because in addition to making forestry more effective, it converts thickets into heat and electricity. Often the forest owner receives a noticeable compensation for the raw material sold.

The harvesting amount and area of energy wood will triple if the objectives of the National Forest Programme for the year 2015 are realised. The target of the programme is to raise the annual consumption of energy wood to 8–12 million cubic metres. This would mean that almost half of the regeneration cutting areas and a considerable portion of preliminary thinning areas of young forests would be included in energy wood harvesting.

Energy wood is all the wood material which is not accepted by the timber industry and which is collected during commercial timber harvesting or for this exact purpose. Woodchips are made from energy wood and then used in the boilers of communal thermal power stations. Also electricity can be produced in many of the stations.

“Energy wood can be chipped in the forest right after cutting and delivered to the end user or otherwise transferred into intermediate storage to await handling. However, energy wood has to be dried in the forest or in storage for at least one summer season. For the forest owner it’s easy to order an energy felling because it can be implemented, for example, alongside the normal intermediate cutting. The regeneration of the forest is speeded up when the logging waste is collected after the final felling. The forest is brought to growth condition and the compensation received from the energy wood covers the felling costs,”Koskitukki’s Energy Wood Supervisor,Juha Hyvärinen, explains the benefits of energy wood felling.

The felling method counts

In energy harvesting, lopped poles and whole tree are gathered for chipping. In the final felling areas the most significant amount of logging waste comes from spruce copses. The logging waste volumes of pine and birch copses are often less than half of the volumes accumulated from spruce copses, so gathering logging waste from them is not very common. Also stubs can be collected from the final felling stands. Good targets are the harvesting areas where fungi have damaged the forest, as well as the harvesting areas of roads or building sites.

Juha Hyvärinen tells the story of a forest owner who ordered an energy wood harvesting for a forest lorry road, the sides of which had grown full of all kinds of “waste trees”.

“The side of the road was full of stout alders, which is the best of fuelwoods. The harvesting costs of energy wood are high but when it’s done using the right method, the harvesting becomes more cost-efficient. With the help of the right forestry equipment, both pulpwood and energy wood can be made at the same time, using the same method. The spacing method is often discussed with the forest owner to ensure that the harvesting trace is the best it can be.”

Subsidised by the state

According to Juha Hyvärinen, energy wood harvesting is presently subsidised through the state’s Kemera subsidy, so it is well worth while.

“Open growths of forest that are too dense dry up if the spacing is not performed in time. Especially in young forests growth losses will arise very quickly if the forest is “poled”. Spacings are very important considering the whole turnover time of the forest,” Hyvärinen reminds us.