It's not news that the roads and bridges in many states are falling into disrepair.

Much of the money to fund maintenance of this infrastructure comes from taxes on fuel, but that's something that doesn't apply to drivers of electric cars--and hybrid drivers pay less than others.

RELATED: Why Electric-Car Owners Should Be Happy For New Colorado Tax

That's led some states to institute fees, intended to recoup the tax revenue on the fuel those cars' drivers aren't buying.

Five states already have these fees, and Wisconsin could become the sixth, according to Greentech Media (via ChargedEVs).

2015 Nissan Leaf

2015 Nissan Leaf

The proposed $50 annual charge would apply to both electric cars and hybrids, and is expected to raise $4 million by 2017--part of $751 million in new fees and taxes proposed by the Wisconsin Department of Transportation.

It's intended to ensure that drivers pay their "fair share" of road-maintenance costs, state DOT Secretary Mark Gottlieb wrote in a letter to Governor Scott Walker.

Colorado, Nebraska, North Carolina, Virginia, and Washington currently charge an extra fee for electric cars, but this move would make Wisconsin the only state to put a fee on hybrids.

MORE: Virginia Sees Sense, Scraps 2013's Hybrid Vehicle Tax

Virginia dropped its $64 charge for hybrids earlier this year.

The Wisconsin plan would also maintain the existing $75 registration fee for gasoline cars, and increase gasoline and diesel taxes.

Naturally, the proposed fee is attracting criticism from environmental groups, including 1000 Friends of Wisconsin, which claims it would penalize buyers for choosing more-efficient cars.

It notes that the DOT has seen consistent funding increases over the past four years, and claiming the fee is a form of political retribution by the Republican administration against the stereotypical Prius-driving Democrat.

2015 Nissan Leaf

2015 Nissan Leaf

These comments echo those of green-car advocates in other states, who feel these fees do more to target certain drivers than they do to raise money to replace increasingly-shrinking gas-tax revenues.

While fees ensure that hybrid and electric-car drivers pay something, they're not a straight replacement for a tax. Unlike a gas tax, they don't apply to out-of-state drivers, for example.

The fee also presumably wouldn't apply to vehicles that use alternative fuels--like natural gas or propane--but still use state roads all the same.

That hasn't stopped other states from issuing ownership fees, though, so it will be interesting to see how things play out in Wisconsin.


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