Carnegie Mellon University

The Piper

CMU Community News

Piper Logo
September 29, 2011

Bigger Isn't Better: Benefits of Plug-in Vehicles Depend on Battery Size, CMU Study Says

Electric CarIn a study appearing this week in the Proceedings of the National Academy of Sciences, Carnegie Mellon's Jeremy J. Michalek and his co-authors report that plug-in vehicles with smaller battery packs are more efficient in reducing societal costs for health care, environmental damages and oil consumption.

"Current government policy provides larger subsidies for vehicles with larger battery packs, assuming that larger is better," said Michalek, an associate professor of engineering and public policy and mechanical engineering at CMU. "While larger battery packs allow plug-in vehicles to drive longer distances on electric power instead of gasoline, they are also expensive and heavy, they are underutilized when the battery capacity is larger than needed for a typical trip, they require more charging infrastructure and they produce more emissions during manufacturing."

Read more: