Resource intensities of chemical industry sectors in the United States via input-output network models

Transitioning to more sustainable operations is widely considered to be among the premier challenges facing the chemical industry today. The motivators for such change include an increasingly tightening regulatory regime, increased consumer awareness, and inclination of investors to consider risks associated with lendings to hazardous material industries. As an effort to become greener, chemical industries are making conscious efforts to reduce their resource intensities or footprints. Such efforts need to be supported by models that can quantify the broad economic and environmental implications of industrial decisions. This manuscript uses the recently developed Ecologically Based Life Cycle Assessment (EcoLCA) model of the United States economy to analyze resource intensities of chemical industry sectors, comparing them with each other and with other industry sectors. The raw numbers are normalized by national flows to gain insight into possible resource vulnerabilities of industrial sectors. These numbers are also aggregated based on their mass or exergy to reduce their dimensionality and permit easier interpretation. Ecological cumulative exergy consumption (ECEC) allows consideration of a wide variety of ecosystem goods and services, human resources and emissions and their impacts on a consistent basis, and is shown to provide unique insight in addition to conventional measures based on mass and Industrial cumulative exergy consumption (ICEC). Ratios of ECEC to money indicate the relative throughputs of natural to economic capital, and are used for investigating supply chains of selected sectors and identifying likely keystone sectors. The insights obtained by juxtaposing resource intensities of chemical industry sectors amongst themselves and with those of the rest of economy are used to identify opportunities for reducing resources intensities of chemical industry sectors that could enable improvement of their environmental sustainability. (C) 2008 Elsevier Ltd. All rights reserved.