ENTIRE INDUSTRIAL SYSTEMS
An early application within Industrial Ecology of ecological concepts to industrial systems
is the design and implementation of so-called industrial ecosystems, or eco- industrial
parks. Industrial ecosystems are characterized by the prevalence of what has been named
industrial symbiosis, a relationship between two or more firms that involves the exchange
of materials, energy, or information in a manner that is mutually beneficial. The most
famous of these is located in Kalundborg, Denmark; its structure is illustrated in Figure 4.
By utilizing what would otherwise be waste products from one firm as input resources for
others, the adverse environmental impact of this system of firms can be greatly reduced.
<Figure 4 near here> Industrial ecologists undertake to design industrial ecosystems
either from scratch or around an existing plant. Kalundborg, however, emerged in the
absence of advance planning and represents a sequence of accommodations and
agreements between pairs of firms. Like any ecosystem, this eco-industrial park is
continually evolving.
New firms may be introduced. Some existing firms increase in size or modify their product
lines and input requirements, while other firms decrease in size or disappear altogether.
Some Industrial Ecologists have turned their attention to larger systems, namely entire
economies, using the concepts and methods of input-output economics, a systems
approach to describing and analyzing an entire economy in terms of the inputs and
outputs of dozens or even hundreds of individual industries, products, and resources. The
use of input-output models in Industrial Ecology has grown substantially in recent years
as their ability to describe both physical stocks and flows and the associated money costs
and prices has been emphasized and expanded.
Input-output models require a database, a large portion of which for past years is
provided on a periodic basis by national statistical offices around the world. When
evaluating scenarios about the future, the framework is reliant on technical data about
resources and products, and it increasingly makes use for this purpose of the kinds of
information originating in MFA and LCA studies.
Input-output studies have investigated such environmentally significant challenges as
water scarcity and water management in different parts of the world including China,
Spain, and Southern Africa; emissions of carbon dioxide and other greenhouse gases; and
the management of a variety of wastes. Emissions of carbon, sulfur, and nitrogen under
alternative scenarios about future technological attributes have been estimated for the
world economy described in terms of the production and trade in the outputs of a few
dozen industrial sectors in over a dozen geographic regions.
As concern builds that the industrialized countries are appropriating disproportionately
large shares of the earth’s resources via resource-intensive imports from developing
countries, input-output models of the world economy that incorporate data from MFA
and LCA studies are certain to become more prevalent. An input-output model can
represent the complex interplay of ecological and industrial system concepts. Since being
introduced in a modified form into ecology, input-output models have been valued by
ecologists for their ability to track the paths of flows, thus accounting for indirect as well
as direct interactions and allowing for a more accurate estimate of the total (direct plus
indirect) energy and biomass requirements. Input-output techniques have also been the
basis for developing measures of ecosystem structure, such as throughput and cycling,
which have been applied to the analysis of numerous ecosystems. [cross-reference to
input-output analysis of biological ecosystems, this volume] The direct relevance of these
ecological system measures to industrial systems is evident, especially when recycling of
resources is of major interest. As a result these ecological measures have recently been
introduced into Industrial Ecology in, for example, analyzing material flow in the nylon
tufted carpet industry.
Consumption and Sustainable Development
Since its origins, Industrial Ecology has been mainly concerned with reducing the
environmental impact of the use of energy and materials in industrial production by
improving the efficiency of production processes. Some industrial ecologists have claimed
that material inputs could be reduced by substantial amounts (e.g., a factor of four or
even ten) without diminishing economic growth.
Such technological prescriptions are mainly addressed to public policy-makers and
corporate executives on the implicit assumption that they would not require much change
in the motives or behaviors of consumers or negatively impact their well-being. Recently,
however, a new emphasis on consumers and consumption has emerged. Many
researchers came to doubt that reliance on changes in the sphere of production alone
could achieve the required scale of impact. The inflow of social scientists into Industrial
Ecology brought the recognition that households are the major decision makers regarding
consumption, and analysis about alternative consumption behaviors should be addressed
in the first instance to them.
In a consumer society, industrial stocks and flows are demand driven, in contrast to the
dynamics governing the availability of traditional materials in ecosystems. In an
ecosystem, predators have control over the number of prey they seek to consume, but
they have no direct control over the number of prey potentially available for
consumption.
By contrast human consumers, particularly in the most affluent, industrialized economies,
have control over not only how much gets consumed but also over what gets consumed
and produced -- and through this connection potentially over how it gets produced. Life
cycle analysts and input-output economists have produced a substantial body of work
analyzing the environmental impacts of different types of households and their
consumption activities. Most attention has focused on motorized mobility, housing, and
intake of food because of the demonstrably intensive use of resources to satisfy
consumption requirements in these areas. The objective of this research is to explore
alternative ways for satisfying the human need for food, housing, and mobility with less
environmental damage. Recent studies have provided a framework for bringing physical
measures into the analysis of Social Accounting Matrices, datasets compiled by a number
of national statistical offices that describe the consumption patterns of distinct types of
households. A special issue in 2005 of the Journal of Industrial Ecology is devoted to the
industrial ecology of sustainable consumption. Such investigations are part of a broader
inquiry about the sustainability of systems and, in particular, sustainable development see
entry in this volume] of the global economy.
Development of alternate energy systems that can substantially reduce reliance on fossil
fuels by making more direct use of solar energy in both production and consumption, thus
moving industrial systems back in the direction of ecological systems, promises to be an
active area of research. A shift in the diets of the affluent from animal-based toward more
plant-based foods could have substantial impacts on resource use in agriculture. Such
scenarios about the future will be analyzed using frameworks that integrate material flow
data, life-cycle descriptions of products and processes, and input- output models of
individual economies and of the world economy. As increasing numbers of researchers
with roots in different disciplines turn their attention to the challenges of sustainable
global development, the distinctive contributions from Industrial Ecology will reflect its
origins in the ecology of the industrial system.
