2013 Nissan LEAF (© Nissan North America)Click to enlarge picture

The 2013 Nissan Leaf topped KBB.com's top 10 list of green cars.

With gas prices in a constant state of flux, and the federal government offering as much as $7,500 in incentives to buy "green" cars, it would seem the only question for someone buying a new vehicle is which one do I pick?

If it were only that simple; however, Kelley Blue Book's website, KBB.com, took a stab a making that decision a bit easier by putting out its list of Top 10 Green Cars for 2013. The car in the top spot shouldn't be a big surprise: the 2013 Nissan Leaf.

"You won't find an all-electric car that offers a better balance of range, practicality, refinement and value than the Leaf," according to the story on the company's website. "Nissan reduced the Leaf's starting price by $6,000 for 2013, so after the $7,500 federal tax savings, you can go all-electric for about $22,000."

The rest of the list for 2013 in descending order includes: Tesla Model S; Ford Focus Electric; Chevrolet Volt; Toyota Prius Plug-in; Ford C-Max Energi; Volkswagen Jetta Hybrid; Honda Fit EV; Toyota Avalon Hybrid; and Lincoln MKZ Hybrid.

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"A growing number of eco-conscious drivers are going 'green' when it comes to the new car they choose to drive, and auto manufacturers have primed the pump with the widest array of offerings in the 'Green Car' segment than ever before," said Jack R. Nerad, executive editorial director and executive market analyst for Kelley Blue Book's KBB.com.

Surprisingly, Ford boasts three vehicles on the list — Focus Electric, C-Max Energi and the Lincoln MKZ Hybrid. It's a surprise only because Ford is mired in a class-action lawsuit that alleges the maker's mileage claims on its C-Max Hybrid as well as the Fusion Hybrid, which is the MKZ's sibling, are "false and misleading." Ford denies the claims noting that driving styles greatly impact the mileage figures and countered is has seen results that exceed the company's listed fuel economy figures.

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Toyota captured two spots on the list with Prius and Avalon. An appearance by the Prius is as expected, but the Avalon, which reaches 40 mpg, captured the luxury title with KBB.com: "If comfort per gallon were a thing, Avalon Hybrid might be king."

Many of these vehicles are well known to eco-conscious shoppers, but none of them are blowing the doors off dealerships. The best-selling model of the group is the Volt, which moved 22,823 units in 2012. The vehicle with the best mileage rating, the Honda Fit EV at 118 mpg, sold just 93 units last year. This is due, in part, because it is available only in California and is only available for lease.

Tesla's Model S topped this pricing list coming in at $62,400, but the site seems enamored with the company's second all-electric offering.

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"One could argue that the 2013 Tesla Model S is the electric car most likely to gain mainstream success. With blistering acceleration, distinct but tasteful styling, abundant interior space and an EPA-estimated 265-mile range, the Model S is among the coolest cars available, electric or otherwise."

Gaining mainstream success is the ultimate goal and that goal just got a little closer to reality thanks to Tesla's founder, Elon Musk. He recently guaranteed that the pricey Model S would retain a resale value similar to Mercedes S-Class as part of a financing plan aimed as assuaging the fears of buyers that they may be "stuck" with the Model S if they wanted to trade it in after three years. In fact, he told reporters during the press conference to announce the financing he'll pay the difference out of his personal fortune, which is estimated at $11 billion, if the company goes under.

KBB.com's Top 10 List of green cars

1. Nissan Leaf

2. Tesla Model S

3. Ford Focus Electric

4. Chevrolet Volt

5. Toyota Prius Plug-in

6. Ford C-Max Energi

7.Volkswagen Jetta Hybrid

8. Honda Fit EV

9. Toyota Avalon Hybrid

10. Lincoln MKZ Hybrid