Electric cars have been around for as long as their gas-guzzling counterparts. But technical limitations such as battery size and efficiency have until recently hampered mass adoption of what is demonstrably a cleaner and more efficient form of fuel-powered transport.

Today, thanks to innovations in how electricity is collected, stored, and discharged, we have recently entered a new era of motorized mobility. Innovations such as high-energy lithium ion battery cells, the development of battery-charging networks, and engineering feats like hybrid drivetrains and regenerative braking, are rapidly making electric vehicles and gas-electric hybrids a new normal. Now, most of the world’s largest automakers either offer eco-friendly electric and hybrid cars or are developing them.

While internal combustion engines will be around for the foreseeable future, fuel economy is climbing thanks to a combination of technological development and regulatory nudges, such as vehicle fuel economy mandates in the United States and European countries, among other nations.

With the new hybrid technologies, today it is possible to own hybrid cars able to drive the equivalent of over 40 miles to the gallon. Fully electric cars fare even better, able to drive the equivalent of over 100 miles on a gallon of gasoline.

While hybrids and electric cars have only been adopted by a small portion of the market, they are growing in popularity. One of the models on this list, the BMW i3 was among the 26 fastest selling cars of 2018.

The following is a list of the most eco-friendly vehicles in the U.S. marketplace for the 2018 model year. All figures come from the U.S. Environmental Protection Agency’s annual review of fuel economy for all passenger vehicles sold in the United States to determine the most fuel-efficient vehicles in the market for the 2018 model year. For electric vehicles, the fuel efficiency figure listed is in MPGe, or miles-per-gallon equivalent, a metric developed by the EPA to translate the fuel economy of vehicles running partially or exclusively on electricity into miles per gallon of gasoline.

In a few cases, multiple versions of a given model have different fuel efficiencies, all of which are high enough to make the list. In those cases, we list only the most fuel-efficient model.

Click here to see America’s most eco-friendly vehicles
Click here to read our methodology