When we first got the Leaf last winter — one of the snowiest on record in Chicago — we discovered that the EV’s range was totally unpredictable. In February, in mostly below-freezing temperatures, the Leaf would show erratic range numbers. In one instance, the range was only 24% accurate from the beginning to the end of the trip. No distance, condition or driver correlated definitively with the range results, according to Cars.com Executive Editor Joe Wiesenfelder.
After 5,000 miles of driving the Leaf since then, we are pleased with the way it performs as a daily driver. But the Leaf isn’t a normal car; it’s an electric car with a finite range before it needs to be charged back up, which can take up the better part of a day. It’s that range number that the driver immediately fixates on when getting in. That’s how you know just how far you have to go before … well, before you’re stuck on the side of the road waiting for a charge.
The variations all the editors experienced were anecdotal, so we decided to study the numbers more. How does the Leaf fare under warmer, more welcoming conditions? And, more importantly, how does it fare after installing the Vehicle Control Module update, which was supposed to help better predict range?
The results were surprising. After going through a month’s worth of driving data (29 trips, totaling more than 350 miles in Chicago’s balmy September) we found that the computer’s predicted range was about 86% accurate on average.
We use the stated range at the trip’s start, on average a predicted range of 91.06 miles. Then we looked at the length of the trip. Our trips averaged 12.25 miles, and the average remainder was 68.65 miles. That means — somewhere, somehow — we’re losing about 10 miles of predicted range.