Hybrid vehicles pair a fuel-burning engine with a battery-powered electric motor to reduce fuel consumption and tail-pipe emissions that contribute to air pollution and global warming. Not only are hybrids good for the environment, they can help wean the U.S. from its dependency on foreign oil. Click here to find out how a hybrid vehicle works.

Hybrid vehicles have been available in the United States since the 1999 arrival of the Honda Insight but sales have ratcheted up this year: 92,558 hybrids were sold in the first half of 2005 – a 255% increase from the same time period in 2004. Hybrids haven't flooded the market enough yet to deflate the $2,000 to $5,000 premium tacked onto the sticker price but it's merely a matter of time before they do. Even with the premiums, if you put on a lot of city miles in a region with high gas prices, a hybrid vehicle may prove to be a money-saver. (Find out if the numbers work for you.) The IRS and state and local governments are sweetening the deal with tax breaks for hybrid buyers. The IRS offers a one-time “clean fuels” $2,000 tax deduction to anyone who purchases a hybrid vehicle this year and the Energy Policy Act recently signed by President Bush includes limited tax credits for hybrid consumers ranging from $250 to $3,400 in 2006 and beyond.

NOT ALL HYBRID VEHICLES ARE CREATED EQUAL
With Priuses being scooped up faster than Toyota can make them, auto manufacturers have been playing catch-up to meet consumer demand. Toyota is doubling its hybrid production which includes the Prius and Highlander SUV. A Camry hybrid is in the works. Toyota also manufactures the Lexus RX 400h hybrid SUV. Honda makes hybrid Accords, Civics and Insights and Ford has entered the scene with the Escape Hybrid SUV and the soon-to-be released Mercury Mariner SUV. Expect a wait if you're interested in a meatier hybrid vehicle – the Highlander and Lexus RX 400h have 2-6 month wait-lists and Ford is already taking orders for the Mariner. A bounty of hybrid vehicles are on the horizon to quell the burgeoning demand: Chevrolet, Nissan, Saturn, and Porsche all have hybrid programs underway.

Amidst this hybrid vehicle buying frenzy, it's important to slow down to study the numbers. EPA mileage figures listed by manufacturers are slightly inflated because they're measured in ideal driving conditions without accounting for traffic, terrain, weather, and other factors so take them with a grain of salt. Sadly, the most recent crop of hybrids suggests that manufacturers have opted for performance over efficiency. The Acura Hybrid sports a V-6 engine but gets the same mileage as a 4-cylinder non-hybrid Accord. You'll pay the $3,400 premium without saving money on gas though you will have a more powerful engine. Test drives by The New York Times report average mileage for the Highlander and Lexus RX 400h that's easily beat by lighter, non-hybrid SUVs or wagons. So, before you plop down the extra dollar for a hybrid, take a careful look at mileage and automotive reviews. Remember that the smallest, lightest vehicle that suits your family's needs will deliver you the best mileage, whether it's a hybrid or not.

THE FUTURE – IT SMELLS LIKE DONUTS
If manufacturers can stay focused on fuel efficiency, there are many promising developments in the field of greener cars.

1. More affordable hybrid vehicles: As production increases, batteries are expected to become lighter, longer-lasting and less expensive. Expect the hybrid vehicle price gap to close in coming years.
2. Plug-in hybrid vehicles: Some true-believers have beefed up their Priuses with more powerful batteries that they can plug-in over night for charging. Their cars run primarily off of the electric motor giving them an upwards of 150 miles per gallon. Since the batteries charge overnight, it's an ideal way to utilize surplus electricity during non-peak hours.
   More Plug-in Info.
3. Biodiesel: Semi-truck drivers have become unlikely pioneers in promoting biodiesel. Using B20, a 20 percent mixture of biodiesel and diesel, drivers report getting 7 MPG instead of 5 MPG while also cutting sooty emissions. Biodiesel, made from vegetable oil, has an exhaust that smells like French fries or donuts. With Willie Nelson as their spokesperson, biodiesel pumps are popping up all over middle America.
   More about Bio-Willie.
4. Biofuels: Already in use in “ flex fuel” cars, corn-derived ethanol is combined with gasoline for a cleaner burning fuel, typically with 85% ethanol, or E85. Carbon dioxide tail-pipe emissions are off-set by the crops grown to produce the ethanol. Ethanol gets fewer miles to the gallon than gas but its domestic production is sustainable and good for farmers.
5. Plug-in biofuel hybrid vehicles: It doesn't take a rocket scientist to see that merging plug-in hybrid vehicle technology with biofuels will deliver a tremendously efficient vehicle. Fareed Zacharia was one of the first people to tout this 500 MPG vision in the mainstream media with his Newsweek column last March.
6. Hydrogen fuel cells: These near zero-emissions cars are powered by a reaction between hydrogen and oxygen. Hurdles exist including cost and practical hydrogen production, storage and transportation. Mainstream availability of hydrogen cars is a good ten years away although Honda announced the first hydrogen car family in June of this year.

More Information

• Consumer Report's Most Fuel Efficient Cars
• Edmund's Most Fuel Efficient SUVs and Pickups
• EPA's Hybrid Vehicle Comparison Chart
• EPA's Green Vehicle Guide
• Union of Concerned Scientists Hybrid Center

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