Read the glossy magazine ads, watch the slick TV commercials, listen to Hollywood celebs rave about their choice of cars on talk shows, and you'll get the idea that hybrid cars can save the planet.

While some of them clearly curb pollution, hybrids aren't the answer - at least not for everyone. Many folks can't afford one, don't like what's available, or want to drive a car that doesn't use gasoline and spew smog into the skies.

Hybrids may be billed as a pollution solution, but they still run on gasoline, and some models increase gas mileage only by 2 or 3 miles per gallon while adding thousands of dollars to the cost of a car.

A group of Bay Area engineers is trying to launch a green car revolution at 100 mpg by souping up Toyota's Prius. The holy grail of their "plug-in hybrids:" less smog, less global warming and a cure for America's oil addiction.

Media: San Francisco Chronicle

"There's a lot of green-washing going on out there," said Spencer Quong, senior vehicles engineer for the Union of Concerned Scientists.

Experts say there are plenty of other options for motorists eager to combat global warming. Off-the-shelf options range from electric vehicles to conventional gas-powered cars to cars that run on compressed natural gas. For those willing to leave the fossil-fuel grid altogether, there's biodiesel or plug-in hybrid conversions.

Don't write off conventional cars, the experts say. Many gas-powered cars get mileage nearly as high as - or sometimes higher than - many hybrids. Auto manufacturers have begun producing higher-mileage compact cars such as the Honda Fit (35 mpg) or the Toyota Yaris (36 mpg). Of course, as the familiar auto dealer disclaimer says, your mileage may vary. Driven carefully - no quick starts, no high speeds - they can get squeeze more miles out of a gallon of unleaded.

Many used cars on the market also get respectable mileage, and at a far lower cost than even a used hybrid. The EPA Web site includes fuel efficiency ratings for used cars as well as new vehicles.

Quong recommends drivers consider smaller vehicles, depending on their needs and how often they actually use a large vehicle. Drivers with families may need an SUV or minivan, and contractors or landscapers might require vehicles with hauling capacity, he said. For them, he recommends smaller pickups or crossover sport utility vehicles - SUV's built on a car frame.

"There are things people can do without buying a new car," he said. "They can tune up their engines, properly inflate their tires, take the extra stuff out of the trunk. They can take off from stops much more smoothly."

Think plug-in

Electric cars are also an option - even for those who can't afford a $98,000 Tesla or other costly boutique vehicles. Neighborhood electric cars, which cost from less than $10,000 into the $20,000s, are gaining popularity - despite having a top speed of 25 mph in California and a range of about 50 miles.

For many drivers living in urban regions, like much of the Bay Area, that makes electric cars a realistic alternative, according to Marc Korchin, owner of Green Motors, a Berkeley auto dealership specializing in electric cars and plug-in modifications of Toyota Prius hybrids.

Korchin suggests that drivers who already own a conventional fuel car keep it - for freeway driving or longer trips - and buy a neighborhood electric vehicle for jaunts around town, which constitute the majority of trips for many drivers. Korchin calls that approach "a hybrid in two cars." And it's something he practices.

"If I go to work, I get in my electric car and it costs 2 or 3 cents a mile for the 2-mile drive," he said. "If I go to see my mom in Fremont, I take my gas car and it costs 60 cents a mile. When you're driving a gas car, you're driving with an albatross around your neck."

Neighborhood electric vehicles are no longer just golf-cart-style vehicles confined to retirement communities and resorts. Several models are on the market, including the Zenn that Korchin sells, which look like average compact cars - except for the green plug portal where the gas tank would be. Larger models, including sport utility vehicles and small pickups, are also available.

And while the vehicles are restricted to 25 mph, Korchin said, they're not timid.

"They're anything but sluggish," he said. "They've got a lot of torque. You can beat almost anything off the line at a stoplight. You just can't go faster than 25. It's really much less of a limitation than most people think."

Freeway-ready electric vehicles are available, but many of them are costly - ranging from around $40,000 to over $100,000 - and pretty funky looking. General Motors is working on its much-hyped Volt plug-in electric car - a mass-market electric car - but it's not scheduled to be on showroom floors until 2010.

Other options

Other cleaner vehicles available now include compressed natural gas cars, most of which are confined to fleet cars owned by businesses and government agencies. The Honda Civic CNG vehicle is the lone vehicle available to consumers, Quong said, though Toyota has announced plans for a CNG-powered Corolla.

Biodiesel is another cleaner choice, though the fuel is not widely available, and using the fuel may invalidate some warranties. Cars that run on E-85, a blend of 85 percent ethanol and gasoline, are also available at dealerships, but the fuel is hard to find in California.

And for some hybrid owners who want to charge into the future, and boost their mileage to around 100 miles per gallon, businesses including Korchin's will modify their Priuses by installing larger battery arrays, computer software and, of course, a place to plug in the extension cord.

"Commuters have lots of options when it comes to dealing with high fuel prices and global warming," said Quong. "Do research - look for the cleanest car you can afford that meets your needs."

Conventional, hybrid or other?

Is what you're driving the most ecologically friendly vehicle? We culled references that show you how vehicles stack up.

A good reference is a Web site run by California's Air Resources Board - It allows users to search for clean vehicles, compare them, and learn about the various clean vehicle technologies.

The Environmental Protection Agency also offers a comprehensive listing of fuel economy information at The site lists mileage ratings, allows drivers to compare vehicle fuel efficiency, and get mileage ratings reported by other drivers.

And by the beginning of 2009, California drivers will get some extra help. State law will require all new vehicles to display a sticker, like the fuel efficiency label, that shows a 1-10 global warming score and a 1-10 smog score. In both cases, the higher the number, the greener the vehicle.