The American Chemistry Council’s Plastics Division has sponsored two new studies into the environmental impact of utilizing more plastics in automotive vehicles. The life cycle performance of two polymers in comparison to more commonly used steel alloys were assessed using two real-world metal components – a bolster and a running board – over a total service life of 150,000 miles.
The bolster study analyzed a 46 percent lighter plastic front support bolster on the 2010 Ford Taurus, which replaced the 2008 plastic and steel front bolster of the same vehicle. The running board study reviewed a 51 percent lighter plastic automotive assist step (running board) for the Chevrolet Trailblazer/GMC which replaced a previous steel running board on the same model.
The key conclusions of the studies are that the savings of fuel, emissions and other environmental impacts during the “use” stage of a vehicle far outweigh the environmental impacts during manufacturing or end-of-life. In fact, lightweighting the running board on all 148,658 GMC 2007 Trailblazers would reduce the use of energy by an amount equivalent to saving 2.7 million gallons of gasoline over the life of the vehicles.
Lightweighting the bolster on all 70,666 Ford Taurus 2010 models would reduce the use of energy by an amount equivalent to saving 770,000 gallons of gasoline over the life of the vehicles. The full reports and the underlying methodologies have undergone independent critical reviews by Dr. Roland Geyer, Asst. Professor, at David Bren School of Environment at University of California, Santa Barbara; Dr. Allan Murray, President, Ecoplexus Inc., and CTO, Allied Composite Technologies LLC; and Dr. John Sullivan, Environmental Scientist, Sustainable Development Strategies, LLC.
The studies by independent consultant PE INTERNATIONAL, Inc. describe the environmental impacts of the bolster and running board for each stage in the product’s life cycle. The life cycle stages examined include 1) production of upstream resources and energy, 2) product manufacturing impacts, 3) product use, and 4) end-of-life treatment for all materials used throughout the product’s life cycle. The inventory and impact categories assessed were non-renewable primary energy demand, global warming potential, acidification potential, eutrophication potential and smog potential.
Both studies conclude that the lighter weight plastic intensive products examined have lower net impacts over their full life cycles than earlier versions made with metals.
“Many plastics, including plastics composites, have a history of helping to make cars lighter and more agile while enhancing safety and performance,” said Steve Russell, ACC’s Vice President of Plastics. “These studies quantify the contributions of specific plastics parts.”
“Experts estimate that plastics make up 50 percent of today’s vehicles by volume—but only 10 percent of the weight. Since less energy is required to power a lighter vehicle, lightweight and versatile plastics can make an important contribution in helping automakers meet the new fuel efficiency standards,” Russell said.
In addition to making vehicles lighter and more fuel efficient, plastics materials have enabled some of the most significant vehicle safety innovations of the past decades, such as advanced seatbelts and air bags, as well as structural enhancements, such as bumpers, door panels and front fenders that also can play a role in improving passenger safety.
America’s Plastics Makers continue to support federal agencies’ efforts to document the safety of mass reduction in vehicles and to develop predictive engineering tools that assist designers and engineers in incorporating the use of plastics into new vehicles.
This article was brought to our attention by Plastics News