If your wallet is taking a beating from high gas prices and all this talk of green energy has inspired you to shop around for a hybrid car, new fuel-efficiency ratings may help you.

The Environmental Protection Agency (EPA) has ranked 10 hybrid vehicles. Topping the list: the Toyota Prius, which gets 48 miles (77 kilometers) per gallon on city streets and 45 mpg (72 km) on the highway.

The Honda Civic Hybrid is next, racking up 40 mpg (64 km) for city driving and the same as the Prius on the freeway. No. 3 is the Nissan Altima Hybrid, which takes you 35 miles (56 kilometers) per gallon in the city, 33 miles (53 kilometers) per gallon on the expressway.

  • Tied at fourth for providing 31 to 34 mpg (50 to 54 km) per gallon are three cars: the Ford Escape Hybrid FWD, Mazda Tribute Hybrid 2WD and Mercury Mariner Hybrid FWD
  • Two Smart Fortwo models — the Convertible and Coupe — rank fifth, offering 33 to 41 mpg (53 to 66 km)
  • At sixth is the Toyota Camry Hybrid, at 33 to 34 mpg (53 to 54 km) 
  • The Volkswagon Jetta and the Jetta Sportswagon, both stick shifts, are seventh, at 30 to 41 mpg (48 to 66 km)
  • The companion automatic Jettas are eighth, at 29 to 40 mpg (47 to 64 km)
  • The Toyota Yaris stick shift is ninth, with 29 to 36 mpg (47 to 58 km)
  • Rounding out the list: the automatic transmission Toyota Yaris, which gets 29 mpg (47 km) in stop-and-go traffic, and 35 mpg (56 km) on the highway. Most hybrids are automatic, but a few manufacturers offer stick-shift versions.

The EPA didn't rank the efficiency of other alt-energy cars, such as those powered by hydrogen fuel cells. But you can check out their mileage — as well as their "greenhouse gas score," here. The hydrogen-fueled Chevy Equinox, test driven for a Scientific American article, received a 5 out of 10 on the EPA's greenhouse gas scale (and got 17 to 24 miles, or 27 to 39 kilometers per gallon). The EPA did not rate another hydro-car, the 2008 Honda FCX Clarity, also featured in that piece.

For more on clean-running cars, see Steven Ashley's take on the Clarity, part of our new in-depth report on green energy.

(Image by iStockphoto/John Bloor)