Junbeum Kim, Braden Allenby, and Ming Xu May 15, 2007 A Center for Sustainable Engineering Education Module
The integrated human/natural/built systems that characterize the anthropogenic earth are highly complex, interconnected, and overlapping. One way to understand and visualize these complex systems is through conceptualizing them as networks. The theory of networks, and network analysis, have been applied widely, providing a unifying language to describe disparate systems ranging from social interactions to power-grids. Thus, the science of networks is a promising vehicle by which to study, and advance our understanding of, the complicated systems that are at the heart of sustainability and sustainable engineering. A major challenge of sustainability is to visualize all the relevant information on various issues and demonstrate the connections between seemingly disparate factors. Network theory and analysis can support identification of causal loops, help with prioritization of conflicting factors, and facilitate intervention at the right levels. This module is about a set of models and tools collectively based on, and illustrating, a new competency we call “sustainability network theory” or “SNT”. The first part of the module introduces network concepts and examples of their application. The second part develops SNT as a means to reflect and model complex aspects of industrial networks, including interconnections between environmental, economic and social aspects. As this is a cutting edge integration of theory and practice in sustainable engineering, students and practitioners should be encouraged to develop their own applications. The target audiences of this module are advanced undergraduate engineering classes, and graduate classes in sustainable engineering and industrial ecology. This module is part of a series designed for the Center for Sustainable Engineering (CSE). Instructor’s guides and further information are available at the Center’s website (www.csengin.org).
Keywords: Industrial ecology, network theory, complexity, industrial ecology theory, sustainability
Sustainability Network Theory and Industrial Systems
Junbeum Kim, Braden Allenby, and Ming Xu
1. Introduction The classic definition of “sustainable development” as provided by the Brundtland Commission is “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” (WCED, 1987, at 43) While there are many elaborations on this theme, most recognize that “sustainability” comprises three domains: the environmental/ecological, the economic, and the socio-cultural. Thus, firms are encouraged to attend to their “triple bottom line,” or financial, environmental, and social performance (Allenby, 2005). While conceptually simple, the idea of sustainability is quite difficult to quantify for many reasons, ranging from data inadequacy to hidden value systems and problematic assumptions. In response, the scientific and engineering communities developed the field of industrial ecology, the first, and perhaps most mature, effort to understand the systemic relationships among industrial, economic, and social systems (Frosh and Gallopoulos, 1989; Allenby and Richards, 1994; Graedel and Allenby, 1998, 2003). Industrial ecology has since become institutionalized, with the establishment of an International Society for Industrial Ecology, a Gordon Research Conference on Industrial Ecology, and the Journal of Industrial Ecology. It has become the basis of government policies in countries such as China, where it is the foundation of the “circular economy” policy, and has developed a growing toolbox of methods such as Design for Environment and Life Cycle Assessment. But both industrial ecology theory and methodologies are incomplete in that they have difficulty addressing complex integrated human/natural/built systems, which...