Researchers determined that hybrid and plug-in vehicles with small battery packs could provide cost-effective reduction of greenhouse gas emissions.
The study, conducted at Carnegie Mellon University, determined that although small battery pack vehicles still use some gasoline, they offer greater greenhouse gas reductions per dollar spent than large pack vehicles.
The results suggest that the automakers should focus on vehicles with shorter electrical ranges, rather than those that can travel greater distances on a single charge because they have larger batteries.
Results of this work could affect government and corporate strategy for vehicle electrification and reduction of automobile-based greenhouse gas emissions. The findings could also help provide more cost-effective options for consumers interested in hybrid and plug-in vehicles.
The government has set a target of 1 million plug-in vehicles on the road by 2015 and currently provides incentives for automakers to increase battery pack size. A longstanding goal has been to increase the range of electric vehicles.
The study's results suggest, however, that hybrid electric vehicles and plug-in vehicles with small battery packs may be better solutions. Larger battery packs are expensive and underutilized when drivers travel distances shorter than the range of their battery packs. This means that on many trips drivers are effectively carrying around expensive dead weight.
A given level of resources can provide more small-pack vehicles than large-pack vehicles. In addition, small-pack autos would grant drivers higher utilization at a lower cost--one they are more likely to recoup over the life of the vehicle. Finally, smaller packs could achieve greater greenhouse reductions per tax dollar and consumer dollar, especially if parallel efforts reduce harmful emissions from the electricity grid.