The battery weight in Leaf and Volt is good for safety but bad for roads

The battery packs that power electric cars such as the Nissan Leaf and Chevy Volt are extremely heavy. This feature improves the safety rating of the EV’s, but also leads to more road wear. Since road maintenance is financed mainly with fuel taxes on gasoline and diesel, drivers of the Nissan Leaf and Chevy Volt get a free ride. Taxing drivers per mile rather than per gallon would be a fairer way to fund road maintenance.

Road maintenance is currently funded by the Highway Trust Fund, which is financed by federal fuel taxes set at 18.4 cents per gallon for gasoline and 24.4 cents per gallon for diesel in 1993. Since 2008, however, highway spending surpassed the revenues from the trust fund. To make up the shortfall, the Treasury has had to provide $30 billon to the trust fund.

Contributing to the shortfall is that people are driving more fuel-efficient cars. Drivers of electric cars pay nothing for road maintenance (since they don’t use any gasoline or pay gas tax), yet they still contribute to road damage. Although not having to pay for road maintenance may seem like a good incentive to encourage people to buy EV’s, it fails to address the urgent problems of deteriorating roads and bridges across the nation, which impacts all drivers.

One proposal is to tax people based on the miles they drive rather than tax the gas they use. This “pay-to-play” option would be a fairer way to charge drivers for the use of roads. Such a tax should also be tiered to weight, since a heavier vehicle would cause more wear.

But how much road wear, compared to similar sized cars, do EV’s really cause? An indication that driving EV’s would result in more wear is that, according to recent crash testing, the Leaf and Volt rate more safely than other size-comparable cars because they are heavier:

As small cars by length, width, and passenger capacity, the Volt and the Leaf might seem at a glance to be at greater risk in an accident. But there's one key thing that sets them apart from other small cars: their battery packs are extremely heavy. In fact, the Leaf and Volt tip the scales at 3,370 pounds and 3,760 pounds, respectively.

The Leaf or Volt actually weighs more than a SUV like the Jeep Cherokee, which has a curb weight of around 3,360 pounds.

Since the emissions from gasoline-powered cars cause damage to the environment, some sort of fuel tax should be maintained in addition to a per mile tax. If we expect our road system to outlast the combustion engine, however, drivers of electric cars need to start paying for the roads too.