While individual states and the federal government continue to incentivize the purchase of plug-in hybrids and full electric cars, one state in particular-Maine-doesn't, and is considering charging extra fees for those vehicles instead. According to the Portland Press Herald (via Hybrid Cars), Maine's Department of Transportation is mulling whether to jack registration fees on greener vehicles: $150 for gas-electric hybrids and $250 for full electric cars. The reason? Road taxes.

As hybrids and EVs consume less gas, they contribute a smaller amount to the state's overall gas-tax revenues, money that's used to maintain roads, bridges, and other transportation infrastructure. "The idea is that the owners of these types of vehicles are paying far less in the gas tax than other vehicle owners and they are using the highway system just like any others," said Meghan Russo, manager of legislative services for the MDOT, to the Press Herald. "There has got to be a way to try and capture revenue from those drivers who are using our road system." Meanwhile, drivers of the targeted vehicles aren't too pleased about the prospect of paying more for registration.

"I feel like I am being punished if this bill goes through because I am doing the right thing," said Gretchen Ebbesson-Keegan, a retired teacher from Camden, who drives a nine-year-old Toyota Prius. "At some point, we have to take a stand on transitioning to alternative energy. They need to come up with a way to take care of the roads that does not set people against one another." In all, hybrids and EVs make up less than 3 percent of the total vehicles registered in Maine. Even with the extra fees collected from owners of those cars-which the Press Herald estimates to be $2.9 million annually-Maine is still tens of millions short in funding infrastructure projects and maintenance.

Other ideas, such as redirecting the sales tax collected on cars and car parts toward the state's highway fund, have also been considered.