Environmental performance of north american wood panel manufacturing
Manufacturing building products such as wood panels has environmental impacts, including contributions to climate change. This paper is a compilation of four studies quantifying these impacts using the life-cycle assessment (LCA) method on five wood-based panel products made in North America during 2012. LCA is an internationally accepted and standardized method for evaluating the environmental impacts of products. Using LCA, holistic environmental impacts were calculated based on survey data from mills on emissions to air and water, solid waste, energy consumption, and resource use. The present study incorporated cradle-to-gate production of nonwood materials including additives and energy products, such as natural gas and coal, consumed at the production facilities. In addition, primary transport of wood materials to the production facilities was included. These primary data were entered in LCA modeling software on a production unit of 1 m3 of the panel to estimate manufacturing gate-to-gate lifecycle inventory (LCI) flows and major environmental impacts. The LCI flows and environmental impacts were converted to a functional unit of 1 m2 of the wood panel (i.e., final product) produced. The following products were evaluated with their stated panel thicknesses in millimeters: oriented strandboard (9.5), southeast (SE) and Pacific Northwest (PNW) softwood plywood (9.5), cellulosic fiberboard (12.7), and hardboard (3.2). Results are provided here on cumulative energy consumption and global warming impacts. Cumulative energy consumption was 74.0, 73.5 (SE), 68.7 (PNW), 76.0, and 88.3 MJ/m2, with biomass energy percentage of 50%, 50% (SE), 64% (PNW), 12%, and 47 %, respectively. Global warming impact was 1.97, 1.90 (SE), 1.23 (PNW), 3.91, and 2.47 kg CO2-equivalent/m2, respectively. The panel products evaluated here are mostly not interchangeable, thus results for the panel products should not be compared. Using woody biomass energy for panel production reduces their impact on climate change.