Interview with Sveaskog, Sweden's largest forest owner:
More biomass needed - Forest industry adapts!
The market for forest fuels is changing shape. This year, Swedish prices for forest biomass for the first time reached that of pulp wood. Sveaskog, the largest forest owner in Sweden, is re-evaluating its 100-year-old forest care strategy which is based on extracting as much lumber as possible from the forest. The countries of the world are clamouring for biomass in order to meet mandatory requirements for renewable energy.
“The Swedish Forest Agency says that Sweden can increase the extraction of forest fuels by 300-500 %”, says Roger Johansson, bio fuel coordinator at Sveaskog, “from 10 TWh to 35-55 TWh. Currently there is a gap between supply and demand and this situation will continue to carry the development quickly forward.”
At Sveaskog biomass-based fuels now comprise a product segment of its own, and is the segment growing the fastest.
More branches and tops can be extracted
Removing more branches and tops from the forest can increase the amount of forest fuels. Transportation is a key issue in making this profitable. As early as 10 years ago, Sveaskog began using a machine that could compress the branches and tops into compact bundles. However, back then both the interest in and price of biofuels were low and the development came to a halt. The bundles provide a 10-20 % greater volume from the forest and improve the transport economy.
In traditional forest felling, the branches and tops protect the ground from the heavy forest machinery. But will the ground hold when driving over it without this protecting layer?
“Certain types of ground withstand more than others and we will have to adjust our extraction to that fact. Development of forest machinery is needed in order to spare the ground”, says Johansson. “There is a prototype of a forest machinery with 10 wheels in Finland which reduces the damage to the ground by 20-30%.”
Nutrients returned with ashes
The research surrounding the ecological impact of extraction of branches and tops has gone on for a long time and there are today clear guidelines which take into account the environment and the nutritive balance of the soil.
The nutrients lost with the forest fuel can to a certain extent be replaced with a mineral-rich ash. Returning the ash is necessary but costly. The ash is taken from the district heating plant or industrial boiler where it is produced to a plant where it is sintered and crushed to get a product with a slow nutrient release. Then it is transported to the forest for spreading. It is important that the ash is from biomass boilers that burn forest biomass and nothing else. Ash from demolition timbers and impregnated timber may contain environmentally hazardous substances.
Photo: Leif Öster
Making use of the stumps
There are various ways to further increase the extraction of forest fuels. Making use of the stumps after a felling is the most promising. For the past four years, a pilot project has been going on with stump extraction on 600 hectares of land in central Sweden. During the autumn of 2009, the Swedish Forest Agency will release new guidelines and then stump extraction can become commercial.
“The economy of stump extraction is still a problem”, says Johansson. “Specially equipped excavators are needed and the technology is far from perfected; one proceeds through trial and error.” Forestry research in Finland and Sweden cooperates on the development of these machines.
The stumps must then be disintegrated to avoid bulky transports. The traditional wood chipping with knives does not work well as stumps contain stones and gravel. If one chooses crushing instead, the awkward stumps must be hauled to a crushing terminal. The optimal is to have smaller crushing units that can be placed in the forest. There is also an ongoing pilot project with this kind of equipment and the technology needs to be developed further.
Research on the ecological impact
However, there is still a knowledge gap pertaining to the effects on the land, water and the biological diversity from large-scale extraction of stumps. Research is ongoing and the Swedish Forest Agency is recommending keeping stump extraction at a low level while waiting for the research results.
“One cannot take the stumps from every kind of ground, such as in shallow soil depths or extremely dry or wet grounds. The stumps improve the ground’s nutritive composition when it breaks down and it counteracts erosion. From other types of ground we know we can take stumps. There is a grey area in between the two where we need to study more.”
There are also insects, lichens and fungi that are dependent on dead wood and could be affected if the stumps are removed. The effects depend on the kind of wood and where one harvests.
Delivery swaps for better logistics
The logistics within the forestry industry are complicated but well-developed with regard to timber and pulp wood. The customers are often located far from the forest. In Sweden, there are about 10 large forestry companies and in order to reduce the transportation distances, one “swaps” timber. Those who have forests near a customer provides the timber to them even if it is sold via another forestry company. Such efficient logistics are still not in place for biomass but is under development. Once in place, both the economy and the environment will be positively affected.
Biofuel competing with timber?
“The price of forest biomass has increased by 5-10 % each year over the past ten years. This year is the first time that Sveaskog sold pulp wood as bio fuel”, says Roger. “If the price trend continues at the same rate for another ten years, the price of forest biomass can compete with the price of timber.”
Text: Elisabeth Kempemo, Logos Kommunikation