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Investigating the Targets for the U.S. Light Duty Vehicles’ Fuel Efficiency and Greenhouse Emissions


Corporate Average Fuel Economy (CAFE)


The National Research Council (NRC) released a new report on Corporate Average Fuel Economy (CAFE) and greenhouse standards for U.S. cars on June 18th. The report, titled “Cost, Effectiveness, and Deployment of Fuel Economy Technologies for Light-Duty Vehicles,” offers an independent assessment of the challenges and benefits of various technologies that are expected to contribute to meeting new standards implemented in 2012. These CAFE and greenhouse gas standards will require the U.S. new light duty vehicle fleet — passenger cars and light trucks offered for sale — to double its fuel economy by 2025.

The new standards, developed jointly for the first time by the National Highway Traffic Safety Administration (NHTSA) and the U.S. Environmental Protection Agency (EPA), are due to be reviewed in 2017 for the automakers’ implementation hurdles and successes. The NRC report is contributing to this analysis.

Anna Stefanopoulou, University of Michigan Mechanical Engineering Professor and Director of the University’s Automotive Research Center participated in the study.

“Light duty vehicles are contributing to 15 percent of CO2 and other greenhouse gases. So, they are to blame for the 15 percent of global warming or 15 percent of how humans adversely and perhaps irreversibly affect our planet,” said Stefanopoulou. “This report looks into an important step our nation is taking toward taming this 15 percent monster.”

Stefanopoulou was involved with a dozen other committee members to help to review powertrain technologies (engines, electrification and transmission) and especially the effectiveness of modeling, optimization and control vehicle fuel consumption.

According to Stefanopoulou, these last three years were very intense; a tremendous undertaking and specially rewarding due to the collaboration with exceptional individuals from industry, academia, and the non-profit public sector.  

Apart from Stefanopoulou’s contributions as a committee member, Dr. Jason Martz, Dr. Robert J. Middleton and Dr. George Lavoie from the ME department fed this report with an important analysis through their “Full Vehicle Simulation Study” commissioned by the committee.

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