Energy use and environmental impact of roundwood and forest fuel production in Sweden

The increasing awareness of climate change issues, unstable fossil fuel prices and concerns about energy security are leading to a rising demand for forest products. If meeting this demand involves increased harvesting it is essential to employ efficient systems that allow sustainable forest management. This thesis examines the environmental performance of the Swedish forestry system and potential opportunities to improve this system. The focus was on roundwood and forest fuel procurement and timber transport, which were evaluated using a Life Cycle Assessment perspective. To evaluate the greenhouse gas savings from forest fuel, the dynamics of soil carbon stocks and the potential to replace fossil fuel were examined. Production of roundwood and forest fuel required little external energy and emitted low greenhouse gas emissions. About 3% of the inherent energy available in roundwood and 2-5% of that in forest fuel, logging residues and stumps was required in forest fuel production. More energy was required in northern Sweden than in southern Sweden, mostly due to higher energy use in transport operations. Secondary transport of roundwood and forest fuel comprised about 50% of energy use, which could be decreased by reducing the road transport distance by modal changes, e.g. between lorry and train, increasing the loading factor, decreasing the fuel requirements of vehicles and using an energy carrier with good environmental characteristics. There were great greenhouse gas savings when forest fuel, stumps and logging residues, replaced fossil fuel. Important factors when assessing the greenhouse gas savings from forest fuel, were the efficiency of the end use, type of fossil fuel substituted, allocation method, site productivity, intensity of the harvesting and bioenergy source (stumps or logging residues). Increasing the use of forest products and forest fuel may decrease energy use and emissions of greenhouse gases if fossil fuel and petrochemical-intensive products can be substituted. However, this can have other environmental impacts, indicating potential conflicts between different environmental areas