Steel body announces environmental impacts of materials decisions in Vehicle GHG Emissions

UNITED STATES May 23 2016 4:40 PM

NEW YORK (Scrap Register): The Steel Market Development Institute (SMDI), a business unit of the American Iron and Steel Institute (AISI), announced results of a study, “The Importance of the Production Phase in Vehicle Life Cycle GHG Emissions.” The study shows the material production phase accounts for a significant portion of overall vehicle life cycle emissions; therefore, it must be considered as part of any overall regulatory program to reduce vehicle emissions.

The study compared greenhouse gas (GHG) emissions of advanced high-strength steel (AHSS) and aluminum sedans, trucks, SUVs and alternate-fuel vehicles. This study showed AHSS-intensive vehicles to have lowest total GHG emissions. Results also showed materials production accounts for nearly 20 percent of total GHG emissions for internal combustion engine vehicles, and as much as 47 percent for battery electric vehicles.

“Many studies on vehicle life cycle emissions have been completed in the auto sector, with varying results,” said Lawrence W. Kavanagh, president of SMDI. “We elected to test the sensitivity of input parameters, and when we applied credible, transparent and independently verifiable parameters, the AHSS vehicles had lower life cycle emissions in all vehicle classes. When we opened up the parameters to conditions more favorable to aluminum, the steel-intensive vehicles had lower life cycle emissions in approximately 70 percent of the cases.”

“Our study shows the difference in life cycle emissions is a few percentage points when comparing single vehicles,” Kavanagh continued. “The more significant point is the difference in production emissions for steel and aluminum - production of aluminum is four to five times more emissions intensive than production of steel in North America.”

“We need to look beyond the tailpipe when considering vehicle regulation,” said Dr. Jody Hall, vice president —automotive market for SMDI. “It is clear the only way to assure vehicle regulations result in a decrease in emissions is when new vehicles have lower combined production and tailpipe emissions than the vehicles they replace.”

The study also concluded that, in the future, as fuel economy increases driving emissions will decrease making production emissions even more significant.

“Production emissions from competing materials can be up to 20 times higher than steel, and therefore should be accounted for,” said Hall. “When we scaled the single vehicle results to an entire annual fleet, the results showed a net increase of GHG emissions of about 4 to 40 million metric tons depending on vehicle segment and overall volume.”