Environmental potentials from wood cascading: A future-oriented consequential yet dynamic approach considering market and time-dependent biogenic carbon effects for selected scenarios under German conditions

Abstract

As sustainable forestry limits the roundwood supply, wood cascading emerges as a promising concept to meet the growing demand resulting from Germany's transition to a bioeconomy. To assess the environmental impacts of wood cascading resulting from shifting the incineration of recovered wood and the associated substitution of future energy mixes and materials, a consequential life cycle assessment (CLCA) of a wood cascading system providing glued-laminated timber (GLT), particleboard, heat, and electricity is conducted. The assessment of environmental consequences requires a holistic approach, including future-oriented German energy and market scenarios. Furthermore, to analyze the impact of biogenic carbon dynamics, this CLCA was coupled with a dynamic life cycle assessment (DLCA) considering forest growth scenarios and temporal aspects. The results indicate a strong influence of market shifts related to material substitution, followed by energy substitution on the environmental impacts of wood cascading. In fact, the results endorse the implementation of the concept of high-quality wood cascading for substituting non-wood products in Germany, as a transformational path towards a bioeconomy and the achievement of net greenhouse gas neutrality. Compared to the effects of the material and energy substitution scenarios, the forest growth scenarios, which focus on tree species composition influenced by future temperature change and CO₂ concentration scenarios, only show a minor influence on global warming impacts. As the findings from applying DLCA contrast with the static approach, it emphasizes the importance of a time-differentiated analysis of biogenic carbon in the evaluation of wood cascading.