When Ford debuted its Escape Hybrid in 2004, it was the world's first hybrid SUV. Today, the Escape, its corporate twin the Mercury Mariner and their cousin, the Mazda Tribute, all vie for the title of the most fuel-efficient SUV on the road. The Escape remains one of the best-selling hybrid SUVs, and it enjoyed a 10 percent sales boost in 2008.

The five-seat SUVs use a 2.5-liter, four-cylinder engine accompanied by a 330-volt electric motor to deliver 34 miles per gallon during city driving, 30 miles per gallon on the highway. The Escape and Mariner are both full hybrids and can run on the electric motor during slow speeds, the gas engine while cruising the highway, or a combination of both, depending on whether efficiency or power is needed more.

While not the most beefy SUVs on the market, they are still rated to tow 1,500 pounds and have a weightier, albeit less efficient, 3.0-liter V6 available. Four-wheel drive is also available.

Ford offers an eight-year, 100,000-mile warranty on all the hybrid-electric components on both vehicles.