New research from the University of Michigan Transportation Research Institute show a decline in the average mpg for new vehicles sales and that driverless cars in the future may cause more trips.
Average fuel economy (window-sticker values) of cars, light trucks, vans and SUVs purchased in February was 25.2 mpg, down from 25.4 mpg in January and now just 0.1 mpg higher than a year ago. Overall, vehicle fuel economy is up 5.1 mpg from October 2007*, the first full month of monitoring by researchers Michale Sivak and Brandon Schoettle.
Regardless of fuel economy, autonomous driverless vehicles may reduce the number of vehicles a family needs, but may lead to an increase in total miles driven, reported Sivak and Scholettle.
They examined U.S. National Household Travel Survey data and found a general lack of “trip overlap” between drivers within a majority of households based on vehicle sharing. The study is based on sharing of completely self-driving vehicles that employ a “return-to-home” mode, acting as a form of shared family or household vehicle, creating a possibility of more trip.
In the most extreme scenario, self-driving vehicles could cut ownership from an average of 2.1 vehicles to 1.2 vehicles per household (43%).
On the other hand, the shift could result in a 75% increase in individual vehicle usage from 11,661 to 20,406 annual miles per vehicle (this increase in mileage does not include additional miles that would be generated during each “return-to-home” trip).
*The average sales-weighted fuel economy was calculated from the monthly sales of individual models of light-duty vehicles and the combined city/highway fuel-economy ratings published in the EPA Fuel Economy Guide for the respective models.