Many have noted that Total VMT has flattened over the last 7 years and that VMT per capita has dropped over the last 10+ years. Generally people think that this shows that we're moving away from a car-oriented society as more people choose to bike, walk and take transit. I generally agree. But someone recently asked me if I thought that GPS-based directions were partly to credit for this. Afterall, wouldn't better directions result in more efficient driving?
Even if they do, and anyone who has used the devices knows that sometimes they direct drivers on weird routes, I suspect the bulk of driving is done by people who know exactly where they're going, because they go there 5 times a week. But that's just a hunch.
It's an interesting theory though.
The finding in economics is that in general increasing efficiency makes the cost of a good to the end consumer lower, which leads to increased consumption. So if GPS generally makes driving less costly by making trips shorter and faster, people will tend to drive more. Whether this results in a net increase depends on the elasticity of demand.
This doesn't bode well for using efficiency mandates to curtail consumption. If I'm forced to have a more efficient air conditioner, I'm likely to use it more because it's less expensive to run.
Posted by: contrarian | July 13, 2014 at 08:53 AM
I think the effect of GPS is a wash--it reduces the psychic cost of driving someplace you have never been so might increase some driving behavior but for the same reason increases the likelihood of taking more direct routes. But the effect of electrons reducing fossil fuel consumption is promising in more virtual ways. For example, there are no VMTs in the Matrix.
Posted by: Early Man | July 13, 2014 at 01:38 PM
Well, before I had GPS, I sailed just as much. I just hit the bottom more more often. Hope that helps.
Posted by: Smedley Burkhart | July 13, 2014 at 08:18 PM
My suspicion is that the rising price of motor vehicle fuels has impacted VMT over the last decade more than anything else. When I drive and use GPS, I'm more interested in the faster route than I am in distance because it's usually driving in traffic or a long distance. So in my case, the routes are usually slightly longer.
Posted by: T | July 14, 2014 at 08:59 AM
GPS use by companies might have a larger effect. Big thing by UPS/Fedex a few years ago that they mapped out their routes to avoid all left turns.
Posted by: charlie | July 14, 2014 at 09:22 AM
I have almost cut my VMT in half over the past 10 years. I don't own a GPS device (not even a smart phone). I just don't like to drive and bike when I can. I have also become less of a stuff person. So I rarely go shopping to mall and the like, and when I do most the time it is online.
I will admit cost was an inspiration at first. With everyone complaining about high gas prices, I just decided to do something about on my own. I changed my lifestyle. I am on my forth tank of fuel this year. I spend less and am happier not driving so much.
Posted by: twk | July 15, 2014 at 09:38 AM