ACQ-treated veneer based composite VBC hardwood hollow utility poles from mid-rotation plantation thinned trees: Life cycle GHG emissions

Hardwood plantations are slow to mature with low financial returns in the early stage. Veneer Based Composite (VBC) products from mid-rotation plantation thinned trees are currently being developed at Griffith University in partnership with the Salisbury Research Centre, Queensland Government, which may offer an opportunity to improve the industry’s profitability and win new markets. Due to shortage in utility solid hardwood poles, VBC poles are proposed as a potential alternative. In this study, greenhouse gas emissions of alkaline copper quaternary (ACQ) preservative-treated VBC pole was assessed using ‘cradle to grave’ life cycle assessment methodology. ACQ preservative was used to extend the service life of wood poles due to wood products are commonly to be degraded in wet environments subject to microbial or insect attack. The manufacturing process considered in this study is based on the current technologies in Salisbury Research Centre. Two (2) end-of-life scenarios were considered: landfilling and incineration with energy recovery. The function unit was a 1-metrelength pole with 115mm internal-diameter and 15mm wall-thickness. Global warming potential (GWP100) was calculated using the IPCC 2007 method. Results indicated disposal stage contributed the most impact. Incineration with energy recovery had the lowest GWP impact (0.337kg-CO2-Eq) followed by landfilling. Transportation distance was identified as a significant parameter affecting the result. Sensitivity analysis indicated that increasing the transportation distance by 100 km would increase the GWP100 by 21% in the incineration option

A comparative life cycle assessment (LCA) of alternative material for Australian building construction

The use of wood is seen as a sustainable alternative to reduce environmental impacts in building and construction sector. The low quality hardwood logs from plantation thinning are enhanced by producing engineered wood such as laminated veneer lumber (LVL). Nevertheless, engineered wood requires the use of chemicals and energy that may reduce its environmental benefits. A life cycle assessment (LCA) was conducted to compare the environmental performance of LVL produced from forestry thinning and final harvest to steel and concrete. The functional unit used in this study was a 1-m-long structural beam in a continuous beam system of 6-m-span designed according to the Australian standards. The Global Warming Potential (GWP) and embedded energy were assessed. The results indicated that LVL beam from thinned logs presented the lowest GWP impact (5.22kg-CO2-Eq). However, due to significant energy requirements for wood drying, the embedded energy in LVL was 186.78MJ which is only marginally less than steel (216.86MJ) but significantly less than concrete (352.82MJ). LVL from mature hardwood logs had slightly higher GWP than that produced from thinning; mainly due to extra energy and materials consumption in the plantation stage. Furthermore, LVL produced from mature trees had higher embedded energy than steel

A comparative life cycle assessment (LCA) of alternative material for Australian building construction

The use of wood is seen as a sustainable alternative to reduce environmental impacts in building and construction sector. The low quality hardwood logs from plantation thinning are enhanced by producing engineered wood such as laminated veneer lumber (LVL). Nevertheless, engineered wood requires the use of chemicals and energy that may reduce its environmental benefits. A life cycle assessment (LCA) was conducted to compare the environmental performance of LVL produced from forestry thinning and final harvest to steel and concrete. The functional unit used in this study was a 1-m-long structural beam in a continuous beam system of 6-m-span designed according to the Australian standards. The Global Warming Potential (GWP) and embedded energy were assessed. The results indicated that LVL beam from thinned logs presented the lowest GWP impact (5.22kg-CO2-Eq). However, due to significant energy requirements for wood drying, the embedded energy in LVL was 186.78MJ which is only marginally less than steel (216.86MJ) but significantly less than concrete (352.82MJ). LVL from mature hardwood logs had slightly higher GWP than that produced from thinning; mainly due to extra energy and materials consumption in the plantation stage. Furthermore, LVL produced from mature trees had higher embedded energy than steel