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A mixed-unit input-output model for environmental life-cycle assessment and material flow analysis
Troy Hawkins1, Chris Hendrickson, Cortney Higgins
1Green Design Institute, Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Environmental Science & Technology
|March 3, 2007
Summary
This study integrates materials flow analysis and economic input-output models to track economic and material flows. The new mixed-unit model enhances supply chain analysis for materials like lead and cadmium.
Area of Science:
- Environmental Science
- Economics
- Systems Analysis
Background:
- Traditional materials flow analysis models track material lifecycles.
- Economic input-output models assess economic and environmental impacts across supply chains.
- Existing models lack integrated tracking of both economic transactions and material flows.
Purpose of the Study:
- To develop a novel mixed-unit input-output model.
- To integrate materials flow analysis with economic input-output modeling.
- To enable detailed tracking of economic and material flows in response to demand.
Main Methods:
- Augmented a U.S. Bureau of Economic Analysis input-output matrix with U.S. Geological Survey material flow data.
- Formulated mixed-unit input-output models for lead and cadmium.
- Demonstrated model capabilities with illustrative examples.
Main Results:
- The developed model combines the strengths of both materials flow analysis and input-output modeling.
- Achieved detailed tracking of material flows through entire supply chains.
- Provided a framework for analyzing economic and material impacts of production changes.
Conclusions:
- The mixed-unit input-output model offers enhanced capabilities for economic and environmental systems analysis.
- The model facilitates comprehensive tracking of material flows and economic transactions.
- Further research can explore model uncertainty and extensions for broader applications.
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