Life Cycle Carbon Accounting of Thermally Modified Wood in the US Inland Northwest

Abstract

The thermal modification (TM) process has been developed as an alternative to chemical treatment of wood, which increases longevity of lumber used in exterior non-ground-contact applications. In one application, TM is being used to process the abundance of beetle-killed pine in forests of the western US. This study compiled a gate-to-gate life cycle inventory for the TM process using data collected from the first TM facility in the inland western US. The inventory focused on energy use, greenhouse gas (GHG) emissions, water use, and solid waste and analyzed two scenarios for modeling electricity impacts (Montana state average and all renewables). Results show that gate-to-gate GHG emissions for the TM process (excluding carbon uptake in trees) are 0.75 kg CO2e/BF (state average grid) and 0.49 kg CO2e/BF (all-renewables electricity). A case study was constructed to show changes over time in GHG impacts of TM and conventional wood products in exterior siding and decking applications requiring periodic surface treatment.