Assessing fossil fuel substitution through wood use based on long-term simulations

To fully analyze the forestry and wood products sector's impact on climate protection through the reduction of CO2 emissions, it is necessary to integrate all aspects of both carbon storage and the substitution effects of forestry and wood use. Substitution effects are assessed based on specific assumptions derived from life-cycle assessment studies, which for the purpose of comparison usually refer to the respective energy mix. This definition is, however, normative. Different assumptions regarding fossil fuel substitution, such as marginal benefit or changing energy mix, are also possible. This paper discusses which of these alternative assumptions are most appropriate for analyzing fossil fuel substitution and then, based on three different approaches (status quo, changing energy mix, marginal fossil), shows the variation in the results these assumptions provide. The calculations include three different forest management strategies in order to show the effects of forest C sinks and different wood volumes available for use (material and energy). Long-term simulations tracking the C effects of forestry and wood use reveal the greatest variations. These findings are useful for deciding between different forestry management scenarios and strategies for wood product and energy use from a climate protection perspective.