Forest products circular economy in an export-focused jurisdiction: Can it fill the emission reduction gap?

Abstract

The use of post-consumer wood in cascades offers several potential carbon-related benefits, including longer carbon retention, less landfilling, deferred tree harvesting, and increased substitution of emissions-intensive materials. However, the establishment of well-regulated wood cascading systems is limited in many jurisdictions. In this study, we utilized a wood products carbon dynamics model (MitigAna), and data from British Columbia (BC), Canada, to estimate the mitigation potential of cascading uses of wood.

We designed three scenarios: a baseline scenario without cascading, a reuse scenario assuming an 85 % recycling ratio (as the upper bound), and an achievable cascading scenario of different commodity pathways with an average 30 % recycling ratio.

The achievable cascading scenario resulted in a biogenic emission reduction of 1.16 MtCO₂e yr^-1 (2.4 %) compared to the baseline. Further mitigation benefits may be achieved by reducing harvest, potentially leading to an additional 1.1 MtCO₂e yr^-1 reduction. However, as a major wood exporter, the circular economy policies of BC have limited influence, as many of the end-of-life events occur outside of BC and Canada's jurisdiction. If the cascading system were to be implemented exclusively in Canada, the emission reduction would only be 0.2 MtCO₂e yr^-1.

Increasing the recycling ratio from 30 % to 85 % only yielded a further 2.2 % biogenic emission reduction, which suggests a diminishing rate of return for the cascading uses of wood. Jurisdictions therefore may prioritize implementing a simple and cost-effective system initially.

There are economic and environmental challenges associated with collection, sorting, treatment, transportation, remanufacturing and commercialization of the post-consumer wood in cascade. Continued research is necessary to address these challenges and inform the development of effective strategies in this area.