Environmental and economic assessment of utility poles using life cycle approach

Abstract

Due to increasing demand for utility poles and the banning of native forests logging in Australia, it is necessary to find sustainable alternatives to roundwood utility poles. Currently, steel and concrete are the most common alternatives. Veneer-based composite (VBC) is a newly developed product made from hardwood plantation mid-thinning. To assess the viability of VBC, comparative life cycle assessment (LCA) and life cycle costing (LCC) analysis were conducted. Two end-of-life scenarios for VBC pole were assessed: incineration with energy recovery and landfilling. Five impact categories were considered: global warming (GWP); acidification (AP); eutrophication (EP); fossil depletion (FDP) and human toxicity (HTP). VBC pole with incineration showed the best environmental performance, particularly on GWP (63.22 kg-CO2-eq), AP (0.29 kg-SO2-eq), FDP (30.78 kg-Oil-eq) and HTP (2.27 kg-1,4-DB-eq), which are less than half of concrete and steel poles. However, VBC had higher EP than concrete and steel due to use of adhesives and preservatives. VBC pole also had the lowest LCC ($1529), due to use of low-value materials and lower manufacturing cost. The LCC showed that both VBC scenarios performed equally on economic grounds. Sensitivity analysis showed that service life was the most sensitive parameter affecting both environmental and economic results, especially the VBC. Transportation distances and fossil fuel consumption also had significant effects on LCA result. Monte Carlo analysis further revealed that despite the high levels of uncertainties in the input parameters, the overall ranking of the options remained the same with VBC being the best performer and concrete the least.