Price Range: range of manufacturer’s suggested retail price + destination fee for different trim levels
EPA City/Hwy MPG: official mpg estimates for city and highway driving; your mileage may vary
Annual Fuel Cost: assumes $2.85/gallon regular gasoline, $3.00/gallon diesel, with 15,000 miles driven annually at 55% city, 45% highway
Air Pollution Score: from the EPA; zero = most tailpipe emissions, 10 = least
Greenhouse Gas Score: from the EPA; zero = most greenhouse gas emissions, 10 = least
UCS Hybrid Value: from the Union of Concerned Scientists; a measure of the bang for your buck of the hybrid system; best rating is Very High; learn more at Hybrid Center.
ACEEE Green Score: from the American Council for an Energy-Efficient Economy; the higher the score, the more eco-friendly the car; highest 2010 score is 57; learn more at ACEEE’s Green Book online.

2010 Ford Fusion Hybrid

Type: Gasoline-electric hybrid, sedan
Price Range: $28,675 – $32,620
EPA City/Hwy MPG: 41/36
Annual Fuel Cost: $1,096
Air Pollution Score: 8
Greenhouse Gas Score: 10
UCS Hybrid Value: High
ACEEE Green Score: 47

• The best hybrid from an American automaker. Better mpg than the Toyota Camry
• Hybrid, and a legitimate competitor to the Toyota Prius.
• Capable of running up to 47 mph solely on electric power.
• Its fun, intuitive and interactive real-time mpg information screens and feedback icons make it easy to improve your driving habits and maximize the car’s hybrid system.
• Comfortable interior with room for five passengers.
• Smooth drive: Ignore the mpg screen and you might not realize you are driving a hybrid.
• Ties with the Honda Civic Hybrid for best crash safety ratings of the six winners.
• Winner of the prestigious Motor Trend Car of the Year award for 2010. Some experts say it is the most fun to drive hybrid on the market.

2010 Honda Civic Hybrid

Type: Gasoline-electric hybrid, sedan
Price Range: $24,510 – $27,710
EPA City/Hwy MPG: 40/45
Annual Fuel Cost: $1,018
Air Pollution Score: 9
Greenhouse Gas Score: 10
UCS Hybrid Value: High
ACEEE Green Score: 51

• Great option if you prefer a more traditional car design over the “Hey, it’s a hybrid” look.
• The perennial No. 2 green car behind the Prius, the Civic Hybrid remains a great option but faces increasing competition.
• A Top Safety Pick from the Insurance Institute for Highway Safety. Ties with the Ford Fusion Hybrid for best crash safety ratings of our six winners.

2010 Honda Insight

Type: Gasoline-electric hybrid, hatchback
Price Range: $20,510 – $23,810
EPA City/Hwy MPG: 40/43
Annual Fuel Cost: $1,043
Air Pollution Score: 8
Greenhouse Gas Score: 10
UCS Hybrid Value: Medium
ACEEE Green Score: 50

• Most affordable hybrid car available.
• Intuitive real-time driving feedback displays make it easy to maximize mpg.
• Capable of significantly better mpg than the EPA’s estimates with a little effort.
• Has a decent amount of zip; transitions between gas power, electric power and gasoline-electric are super smooth.
• If you don’t regularly need much room for multiple passengers (the back seat is really tight), the Insight may be your best option among hybrids because of its price.

2010 Toyota Prius

Type: Gasoline-electric hybrid, sedan/hatchback
Price Range: $23,550 – $28,820
EPA City/Hwy MPG: 51/48
Annual Fuel Cost: $855
Air Pollution Score: 8
Greenhouse Gas Score: 10
UCS Hybrid Value: Very High
ACEEE Green Score: 52

• The benchmark for green cars, now in its third generation. New version is bigger and more powerful, but still holds the top mpg rating among all cars.
• Capable of electric-only mode at low speeds (up to about 25 mph) and highway coasting.
• Optional solar roof powers a fan that helps cool the interior when parked in hot weather.
• Named best new-car value by Consumer Reports for its reliability and low cost to operate.
• Comfortable interior, with room for five. Solid safety ratings and features (but do ask about the specific car’s brake recall status when you’re Prius shopping).

2010 Volkswagen Golf TDI

Type: Diesel, hatchback
Price Range: $23,104 – $24,809
EPA City/Hwy MPG: 30/42
Annual Fuel Cost: $1,324
Air Pollution Score: 6
Greenhouse Gas Score: 8
ACEEE Green Score: 43

• The best small diesel car for your buck.
• Eligible for a federal tax credit of up to $1,700.
• Sporty drive and looks, but still capable of mpg in the upper 30s or low 40s.
• With 40-plus mpg at highway speeds, the Golf is a great option for primarily highway drivers.
• If maintained, diesel engines typically hold up longer (with better mpg, too) than gas engines.
• May require slightly more ongoing maintenance (which might be covered in the buyer’s package, depending on current offers) than a comparable gas car.

2010 Volkswagen Jetta TDI

Type: Diesel, sedan
Price Range: $23,580 – $24,680
EPA City/Hwy MPG: 30/42
Annual Fuel Cost: $1,324
Air Pollution Score: 6
Greenhouse Gas Score: 8
ACEEE Green Score: 43

• One of the best examples of how clean diesel technology makes diesel cars a competitive green alternative to hybrid cars.
• Eligible for a federal tax credit of up to $1,300.
• A roomy, comfortable sedan. Wagon version also available for more cargo space.
• Great option for primarily highway drivers and/or those with small families.
• Capable of better mpg than the EPA estimates with a little effort.
• More affordable than the Prius, with comparable real-world highway mpg (low to high 40s).
• Long-term reliability projections are good, but the clean diesel system may require a bit more ongoing maintenance than you’d need for a comparable gas car. Warranties and buyer packages may cover some of that maintenance.

Best Green Cars 2010, Runners-Up

Honda Civic GX (natural gas); 24/36 mpg; ACEEE Green Score: 57
Smart ForTwo; 33/41 mpg; ACEEE Green Score: 50

Best Green Cars for the Least Bucks

Chevy Aveo: $12,685; 27/35 mpg (manual trans.)
Honda Fit: $15,610; 27/33 mpg (manual trans.)
Nissan Versa: $10,710; 26/34 mpg (manual trans.)
Suzuki SX4: $14,224; 23/33 mpg (manual trans.)
Toyota Yaris: $13,355; 29/36 mpg (manual trans.)

Best Green Cars if You Win the Lottery

Fisker Karma: plug-in hybrid; $87,900
Lexus LS 600h L: hybrid; $109,675
Tango T600: electric urban car; $108,000
Tesla Roadster: electric two-seater; $109,000

Best Green Cars for City Driving

Ford Fusion Hybrid: 41 city mpg
Honda Civic Hybrid: 40 city mpg
Honda Insight: 40 city mpg
Smart ForTwo: 33 city mpg
Toyota Prius: 51 city mpg
ZAP Xebra: electric three-wheel sedan;
25 miles per charge; about 56 cents of
electricity to recharge

Best Green Cars for Commuters

Audi A3: 42 hwy mpg (diesel)
Chevrolet Cobalt XFE: 37 hwy mpg
Honda Civic Hybrid: 45 hwy mpg
Honda Insight: 43 hwy mpg
MINI Cooper: 37 hwy mpg (manual trans.)
Toyota Prius: 48 hwy mpg
Volkswagen Golf: 42 hwy mpg (diesel)
Volkswagen Jetta: 42 hwy mpg (diesel)

Best Green Sedans

cu. ft. p.v. = cubic feet passenger volume
Ford Fusion Hybrid: seats 5; 100.3 cu. ft. p.v.
Nissan Altima Hybrid: 35/33 mpg; seats 5; 100.7 cu. ft. p.v. (only available in CA, OR, NY, NJ, MA, CT, VT, RI, ME)
Toyota Camry Hybrid: 33/34 mpg; seats 5; 101.4 cu. ft. p.v.
Toyota Prius: seats 5; 93.7 cu. ft. p.v.

Best Green Wagons & Minivans

cu. ft. p.v. = cubic feet passenger volume
Audi A3: 30/42 mpg (diesel); seats 5; 89 cu. ft. p.v.
Dodge Caliber: 23/31 mpg (manual trans.); seats 5; 95.2 cu. ft. p.v.
Honda Odyssey: 16/23 mpg; seats 7; 171.4 cu. ft. p.v.
Kia Soul: 24/30 mpg; seats 5; 102.3 cu. ft. p.v.
Mazda 5: 21/27 mpg; seats 6; 142.1 cu. ft. p.v.
Toyota Matrix: 26/32 mpg (manual trans.); seats 5; 94 cu. ft. p.v.
Toyota Sienna: 16/21 mpg; seats 7; 177.4 cu. ft. p.v.
Volkswagen Jetta SportWagen: 30/42 mpg (diesel) seats 5; 91.7 cu. ft. p.v.

Best Green Cars for Reliability

Ford Fusion Hybrid
Honda Civic
Honda Fit
Honda Insight
Hyundai Elantra
Nissan Altima Hybrid
Subaru Outback
Toyota Camry Hybrid
Toyota Prius
Toyota Yaris
Volkswagen Golf
(Based on reliability ratings from Consumer Reports and JD Power and Associates.)

Best Green Cars for Safety

Audi A3
Honda Civic and Civic Hybrid
Subaru Outback
Volkswagen Golf
Volkswagen Jetta
(Top safety picks from the Insurance Institute for Highway Safety.)

Best Green Gasoline-Only cars

Chevrolet Aveo: 27/35 mpg (manual trans.)
Honda Fit: 28/35 mpg
Hyundai Accent: 27/36 mpg
Kia Rio: 28/34 mpg (manual trans.)
MINI Cooper: 28/37 mpg;
(manual trans.; requires premium gas)
Nissan Versa: 28/34 mpg
Smart ForTwo: 33/41 mpg (requires premium gas)
Toyota Yaris: 29/36 mpg (manual trans.)

Best Green Diesel Cars

Audi A3: 30/42 mpg
Volkswagen Golf: 30/42 mpg
Volkswagen Jetta: 30/42 mpg

Best Green SUVs/Crossovers

Ford Escape Hybrid 2WD: 34/31 mpg
Honda CR-V 2WD: 21/28 mpg
Nissan Rogue 2WD: 22/27 mpg
Saturn Vue Hybrid 2WD: 25/32 mpg
Toyota Highlander Hybrid 4WD: 27/25 mpg
Toyota RAV4 2WD: 22/28 mpg

Best Green Trucks

Chevrolet Colorado 2WD: 18/25 mpg
Chevrolet Silverado 15 Hybrid 2WD: 21/22 mpg
Ford Ranger 2WD: 22/27 mpg (manual trans.)
Toyota Tacoma 2WD: 20/26 mpg (manual trans.)

Great Green Car Hopes for the Future

The new CAFE standards: automakers’ fleets must average about 35 mpg by 2016
Chevy Cruze (up to 40 hwy mpg; 2011)
Chevy Volt (electric car with range extender; 2011)
Ford Fiesta (30/40 mpg; 2011)
Nissan Leaf (electric sedan; 2012 mass production)
Tesla Model S (electric sedan; 2012)
Toyota Prius plug-in hybrid (2012)

John Rockhold is a green car enthusiast and Contributing Editor for MOTHER EARTH NEWS. Find him on Google+.