Application of Life Cycle Assessment and Design Tools to Instrument Panels: Analysis for Common Sense Initiative Pilot Project
Environmental management practices are currently undergoing two important shifts. First, companies, policy makers, environmental organizations and other stakeholders are increasingly focusing on the environmental impacts related to the entire product life cycle instead of concentrating on just one or two discrete stages, such as manufacturing. Second, the U.S. Environmental Protection Agency (EPA) and other regulatory groups are developing more flexible approaches for achieving environmental goals.
In late 1994, the EPA initiated a series of projects called the Common Sense Initiative (CSI) to demonstrate that the early and active participation of industry representatives and other stakeholders could improve the environmental policy process. These projects are addressing a wide variety of issues in six key industries, including the automobile manufacturing industry. The overall goal of these CSI projects is to develop "Cleaner, Cheaper, Smarter" environmental management practices.
This life cycle study of an automobile instrument panel (IP) supported the objectives of the Life Cycle Management/Supplier Partnership Project of the CSI Automobile manufacturing Sector. The framework and computer model developed during this study will enable project members to assess the impact of various environmental improvement strategies and will serve as a foundation for further evaluations.
For this study, an "average IP" was modeled based on the instrument panels of three popular U.S. car models: 1995 Chevrolet Lumina, 1996 Dodge Intrepid and 1996 Ford Taurus. This "average IP" consisted of seventeen (17) different materials and weighed over 22 kg (49 lbs). On a weight basis, the six most significant materials were steel, polyurethane foam, glass reinforced polypropylene, unfilled polypropylene, SMA resin and PVC resin. The other materials were magnesium and a variety of thermoplastic and thermoset resins.
The first life cycle tool applied to these complex automobile components was a Life Cycle Inventory (LCI) analysis. This analysis determined the types and quantities of environmental burdens created during the life cycle of an instrument panel. A thorough evaluation of solid waste production and energy consumption was completed and a partial inventory of air emission and water effluent releases was also conducted. The analytical steps for the LCI analysis were:
1) Specifying the scope and boundaries of the process
2) Diagramming the process
3) Gathering data
4) Determining the energy and mass flows for each stage in the process
5) Summing the energy and mass flows
Two of the more significant environmental burdens revealed by the LCI analysis were the generation of solid waste and consumption of energy resources, especially gasoline. The total amount of solid waste created during the IP life cycle is 29 kg. The majority, 53%, of landfilled material is created during the End of Life phase but significant quantities, 33%, are also produced during Material Production. A total of 7600 MJ of energy were consumed during the IP life cycle. The Use phase dominates with 57% of the total, while the Material Production stage is also important with 37% of the energy use.
A second life cycle tool, Multi-Criteria Matrices, was used because the success or failure of a product system depends on its environmental performance and many other factors. The stakeholders that influence the product life cycle, such as the manufacturer, suppliers, customers, regulators and environmental groups, specify a variety of requirements. The Multi-Criteria Matrices were used to identify and organize these Performance, Environmental, Legal and Cost requirements.
These Multi-Criteria Matrices showed that instrument panels must meet a set of complex and sometimes conflicting requirements. For example, IP's must have the strength and rigidity to support the use of air bags during collisions but must also be lightweight to minimize fuel consumption. Another conflict is the IP's are sometime painted to meet consumer's preference for non-glare surfaces, however this painting process can release air emissions and/or water effluents. The matrices highlighted the requirements that environmental improvement strategies must address.
In the Conclusions section, the following improvement strategies are evaluated relative to their potential for reducing the key environmental burdens and to their ability to meet the specified requirements.
For waste reduction:
For energy conservation:
Additionally, some other strategies that require more substantial systematic change are also described.
While each strategy has different advantages and drawbacks, the options involving more substantial change generally offer greater benefit but face significant technical, social and economic constraints. Regardless of the magnitude of change, the life cycle framework developed in this report can be used to evaluate potential strategies and enhance the overall management decision process.