Many of us might recall that in 1974, the National Maximum Speed Law capped all roads in the US at 55 MPH. The nation was gripped by the 1973 Oil Crisis, so the law was supposed to reduce fuel consumption. It didn’t work very well — mostly because people didn’t obey it!
But the lesson is right: over 50 miles per hour, most cars become significantly less efficient. It’s because of wind resistance, which increases exponentially as your speed goes up.
In real terms, “each 5 mph you drive over 50 mph is like paying an additional $0.26 per gallon for gas,” according to the data magicians at the Department of Energy. That’s a compelling case, with gas still well over three dollars a gallon.
So, should the environmentally-conscious driver should always go 50? I can’t advocate that — it can be frustrating, it’s impractical, and you’d probably get honked at (and possibly worse!). But it is definitely a tip to keep in mind. If everyone did it, we’d achieve a small but meaningful reduction in gasoline use and the pollution that comes with it. In the context of 300 million gallons of gasoline consumed per day in this country, that’s no small change.
Add it to your repertoire of ways to drive a little greener. And, OK, feel good about yourself for saving some fuel and polluting a little bit less.
But if we are to make an impact on the issues we care about — a polluted and changing climate, oil drilling catastrophes, tar sands extraction — we’ll need to do more than reform our speedometer habits. We need a transportation system that doesn’t encourage long-distance trips, we need better electric-car options, and we need more public transit options. And we won’t get there by smugly sitting in the right lane, griping about the planet-haters whizzing by.