Life Cycle Analysis of Glass vs. Polycarbonate Sidelights Natalie Henry Jaymie Meliker Mike Turnbull Melissa Vernon April 14, 1999
Agenda Goals System Overview Life Cycle Costs Impacts - Energy, Solid Waste, Air, Water Drivers Summary Recommendations
Goal Evaluate two automobile sidelight systems Sidelight = all windows except windshield Polycarbonate: –40% lighter than glass –200 times more resistant to shatter Glass: –scratch resistant
System Overview Data Sources: –Eco-profiles of the European Plastics Industry: polycarbonate –Life Cycle Inventories for Packaging: packaging glass
Assumptions Packaging glass data equivalent to flat glass PC does not need scratch resistant coating Equivalent mfg, recycling practices in Europe & US Identical mechanisms for window function during use phase
Polycarbonate Flow Diagram
Glass Flow Diagram
Vehicle of Study Vehicle: Chevy Express G Van Total surface area of sidelights = 51 sq ft Useful life of van = 110,000 miles Fuel Economy = 16.4 mpg
Life Cycle Costs
Energy, Solid Waste, Water Emissions Summary
Air Emissions Summary
Key Drivers PC Glass
Summary of Results Glass Lower environmental impact in Mfg phase Lower total: –Particulate matter –SO2 Lower total cost Polycarbonate Lower environmental impact in Use phase Lower total: –NOx & HC –Solid waste –CO –Lead in air emissions Overall: Neither product system is more environmentally friendly
Recommendations PC Manufacturers Reduce manufacturing costs Improve scratch resistant coating Develop single unit for sidelight & encapsulation Glass Manufacturers Reduce/recover energy used in manufacturing Increase recycled content from 15% to 50% Overall: Improve mpg of automobile End of life material recovery and recycling
Questions & Answers