This is probably not the best time to talk about the social cost of driving, given that many readers are probably planning to drive to see family. But no one is saying that you should never drive anywhere — just that reducing driving has some positive benefits.
The math is simple. The environmental impact of driving equals:
(Emissions/unit of energy) x (units of energy/mile) x (miles traveled).
Environmental regulators have done things to reduce emissions per unit of energy, ranging from catalytic converters to unleaded gas to electric cars. CAFE standards are designed to reduce the amount of energy needed to travel a mile. These programs have really been quite successful. The trouble is that the third factor — the number of miles driven — rose quite a bit while the other changes were going on, counter-balancing the improvements in pollution control and fuel efficiency.
But there’s some recent good news on that front. Since 2007, the number of miles driven has actually been dropping, partly because young people are less likely to even have drivers’ licenses. In fact, according to a recent report, the average American is driving significantly less since 2005. But you ask: isn’t this due to the bad economy or the totalitarian machinations of government planners. As to the first, there seems to be no correlation between the driving loss and state unemployment. Nor is there much of a discernible political correlation — some deep red states are showing significant decreases. Consider Texas: a state that likes to brag about how well it’s weathered the recession, and a place that no one can accuse of socialist leanings. Average miles driven in Texas have dropped 10% since 2005.
The environmental payoff is great: less air pollution and reduced carbon emissions. There’s another dividend, too — less driving means less congestion and fewer accidents.
In the meantime, have a great Labor Day weekend, drive safely, and wear your seatbelt!