Reducing Built Environment Embodied Carbon: A Transport Perspective
摘要
The ‘whole-of-life’ perspective of built assets views resource consumption and emissions across their complete life, not just during the construction phase. Carbon embodiment into the built asset is an aggregation of the carbon embodied into individual elements comprising it. Life cycle analysis has transportation as a significant component, with its involvement within and between stages. In most cases, however, transportation carbon is considered ‘as-is’, with straight take-off of quantities taking transport inefficiencies into their fold. These inefficiencies primarily originate from operational deployment of transport assets, further accentuated by the highly fragmented supply chain, externalised asset ownership and management, and separate materials delivery and waste removal businesses. Optimising construction transport is a complex exercise, which demands integration at various scales, further compounded by need to ‘borrow’ planning and management tools from other domains. This paper examines the plasterboard supply chain in Auckland, New Zealand from the transport perspective. It quantifies transport inefficiency through the potential to reduce travel and fuel consumption. Tools from the supply chain and operations domain are applied for experimentation to improve transport efficiency in terms of loading as well as capacity utilisation and integrating reverse logistics into forward logistics operations. Improved efficiencies are converted into carbon equivalents based on domestic and internationally benchmarked parameters, quantifying reduction in embodied carbon. It draws a comparison of per-unit carbon embodiment in plasterboard between business-as-usual and the re-engineered transportation/distribution models. It employs real-world operational data to bridge the existing research gap of the means to reduce embodiment of carbon in manufactured construction products beyond the manufacturing stage, considered highly variable and expensive and difficult to evaluate. The analysis is specific to the Auckland setting and is meant to be a pointer to the potential for decarbonising the built environment over its life cycle from the transport perspective.