If there’s one thing that keeps people from buying electric cars, it’s range anxiety – what if your battery runs out before you reach your destination? Although most EVs do feature systems that estimate range, they can’t always be relied upon. A new software system, however, is said to be accurate to within two miles.
In existing electric vehicles, range is calculated based on the battery’s charge level combined with the average amount of energy that’s been consumed on the trip up to that point. If users then have to climb a long hill or go on a freeway with a high speed limit (as just a couple of examples), that estimate changes.
This could result in drivers being initially told that they can complete a trip based on their current charge level, only to be informed part way through that it’s no longer possible.
A program developed at North Carolina State University, however, accesses multiple online databases to see what energy-using factors will be involved in getting from the present location to a given destination – this includes things like road grades, traffic levels, speed limits, and weather. It also takes the battery’s charge level into account, along with the performance characteristics of the battery and the vehicle.
Based on average driving practices, it then lets drivers know if they’ll be able to get to where they want to go, without having to stop on the way to recharge.
“This predictive, big-data approach is a significant step forward, reducing the range estimation error to a couple of miles,” said Dr. Habiballah Rahimi-Eichi, lead author of a paper on the research. “In some case studies, we were able to get 95 percent range estimation accuracy.”
www.news.ncsu.edu/2014/10/chow-range-2014/
