Not all green cars are hybrids, diesels, or plug-ins.

And with new fuel economy regulations now set through 2025, all cars are going to get more efficient--gasoline cars first and foremost.

The new 2013 Nissan Altima mid-size sedan has the highest EPA rating for combined gas mileage of any gasoline powered mid-size sedan: 31 mpg.

That breaks down to individual test ratings of 27 mpg city, 38 mpg highway. And it's 1 mpg better than the best Honda Accord and 2 mpg higher than the mild-hybrid Chevrolet Malibu with eAssist.

Sure, 31 mpg combined is far lower than the 47-mpg rating achieved by the new Ford Fusion Hybrid (the Fusion is also a Best Car To Buy 2013 nominee).

But the base Altima with the 182-hp, 2.5-liter four-cylinder engine and continuously variable transmission (CVT)--the one that achieves that rating--starts at $21,700.

That's fully $5,500 lower than the least expensive Fusion Hybrid model. (Both prices are before the makers' mandatory delivery fees are added.)

The new Altima range competes with longtime stalwarts in the segment--the Accord and the Toyota Camry--along with newly refreshed entries like the Fusion and the Chevrolet Malibu, and the Hyundai Altima and Kia Optima.

It's stylish, comes with an impressive array and standard and optional features, and proves that mid-size sedans with competitive prices can offer fuel efficiency ratings higher than anyone might have expected just a few years ago.

For that, we nominate the 2013 Nissan Altima as one of our Best Car To Buy candidates for 2013.

Watch for details on our other Green Car Reports 2013 Best Car To Buy nominees over the rest of this week.


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