Is cascading of harvested wood products really an environmentally beneficial strategy in Finland and Norway?
C A S Hill, G Alfredsen, M Hughes, L R Gobakken
The role of cascading wood waste in the bioeconomy is highlighted in the several strategic documents. The European Waste Framework Directive describes a waste hierarchy where re-use and recovery are considered more favourable options compared with energy recovery, and applies strict re-use and recycling targets to household waste and non-hazardous construction and demolition waste. It is not fully clear if setting such targets will result in a positive environmental benefit. The assumption is generally made that cascading of bio-materials is good and incineration is bad. But how true is this assumption and is it universally applicable? This paper discusses the methodology to be used in order to determine the best strategy for the use of end of life wood waste in Norway and Finland. The scenario considered is that of the cascading of wood at the end of life into different product categories as counterfactuals compared to the incineration of wood with energy recovery. The paper considers both the LCA aspects by comparison of the global warming potential of different scenarios, as well as the storage of atmospheric carbon in the materials. Knowledge gaps that need to be covered in order to determine the best approach to utilising wood waste from an environmental perspective have been identified.
Keywords: cascading, circular economy, end of life, harvested wood products, life cycle assessment, recycled wood waste