Search Results

In recent years, the environmental impact of automotive products and processes has become an issue of increasing competitive importance. Life cycle analysis (LCA) provides a tool that allows companies to assess and compare the environmental impact of a variety of material and process choices. This enables companies to manufacture environmentally sound products of exceptional value by environmentally conscious processes. In this study, we used LCA to compare the environmental burdens associated with three aluminum casting processes: lost foam, semi-permanent mold, and precision sand. We obtained data from one primary and one secondary facility for each of the three processes studied. These data included all of the environmental burdens associated with raw material and energy consumption, gaseous emissions, and waste generation. In addition, we modeled the environmental burdens associated with the production and transport of the materials used during the manufacturing processes.

Federal standards that mandate improved fuel economy have resulted in the increased use of lightweight materials in automotive applications. However, the environmental burdens associated with a product extend well beyond the use phase. Life cycle assessment is the science of determining the environmental burdens associated with the entire life cycle of a given product from cradle-to-grave. This report documents the environmental burdens associated with every phase of the life cycle of two fuel tanks utilized in full-sized 1996 GM vans. These vans are manufactured in two configurations, one which utilizes a steel fuel tank, and the other a multi-layered plastic fuel tank consisting primarily of high density polyethylene (HDPE). This study was a collaborative effort between GM and the University of Michigan's National Pollution Prevention Center, which received funding from EPA's National Risk Management Research Laboratory.

During the fall of 1992, the Michigan Roadside Study was conducted. During this study IM240 tests were conducted on vehicles that had also been emissions tested during on-road operation via two remote sensors that were separated by 100 feet. The use of two remote sensors provided an indication of the short-term real-world emissions variability of a large number of on-road vehicles. This data was used to determine the frequency of flippers, i.e. vehicles that are sometimes high emitters (>4% CO) and at other times low emitters (<2% CO). The data show that the flipper frequency increases for older model year vehicles. Also, the correlations between remote sensor readings of emissions concentrations and IM240 mass emissions rates were determined. The data show that the correlation between remote sensing and IM240 improves with increasing numbers of remote sensing readings. For three remote sensor readings, CO correlates with an r2 of 0.69 and HC correlates with an r2 of 0.54