Biofuels vs. hybrid: Which is the car for you?

Thinking about making the switch to an alternative vehicle? Here are a few things to consider when deciding which choice is a good one for you.

What Are You Currently Driving?

In purely practical terms, the difference between driving a hybrid electric vehicle and a conventional car is one of degrees. So. if you're presently tooling around in a '93 Jeep Cherokee (17 mpg city/21 highway) and decide to switch to a Toyota Prius (60 city/51 highway), you'll be taking a near-quantum leap in fuel efficiency. On the other hand. if your current car is a ten-year-old Geo Metro (44 city/49 highway), the disparity, is far less, especially when considering the economics of driving an $1.100 car versus a $22.000 one.

Those looking at running their vehicles on biofuels face a similar picture. "It depends on what you're planning to use the vehicle for." Charley Wilson, Head Mechanic at The Organic Mechanic in West Asheville, said. Older Mercedes-Benz's running on biodiesel (the current favorite) are a little sluggish, but they're great for long-distance trips. "A lot of people want the old diesel wagons, but the rear suspension on most of them are shot. so that's a repair to look for." Wilson said. Wilson noted that Honda Civics. though having engines that use unleaded fuel. get better gas mileage than most diesels.

But fuel mileage should not be your only yardstick. Environmental issues such as emissions performance are important as well. Oxides of Nitrogen (N[O.sub.x]), Carbon Dioxide (C[O.sub.2]), and Methane (C[H.sub.4]) are the culprit ,greenhouse gases measured for each late-model vehicle in a full fuel-cycle analysis, while Carbon Monoxide (CO), Formaldehyde(HCHO), and particulate matter (PM) are measured m grams per mile over the useful life of the vehicle-usually 120.000 miles.

Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the Clean Air Act. Exhaust emissions of sulfur oxides and sulfate (major components of acid rain) from biodiesel are essentially eliminated when compared to petrodiesel. The use of biodiesel also results in a substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel.

You can access www.fueleconomy.gov and click on "Find and Compare Cars" to determine the emissions ratings of most cars and trucks from 1985 to 2007. Because of ongoing improvements in electronic fuel controls and other technology, the newest cars are also usually the cleanest.

Can You Claim Federal Tax Credits?

Most, but not all, hybrid electric vehicles qualify for a federal income tax credit of up to $3,150 if purchased between January 1, 2006 and December 31, 2010. In order to claim the tax credit, the vehicle's use must begin with the taxpayer--a convoluted way of saying hybrids bought as used cars do not qualify. The credit claim is made on IRS Form 8910 "Alternative Motor Vehicle Credit," and actually includes vehicles other than HEVs: Qualified lean-burn technology vehicles, qualified compressed natural gas (CNG) and liquefied petroleum gas (LPG) vehicles, Flexible-Fuel Vehicles (FFVs) that use at least 85 percent methanol, and cars powered by fuel cells.

Do not despair if you bought a hybrid vehicle prior to the 2006 rule inception. There is still a $2,000 credit available under an older federal program for certain HEVs purchased in 2005.

A tax credit is available to petroleum suppliers who blend biodiesel into their petroleum products. It amounts to $1.00/ gal off the company's excise tax liability if the biodiesel is made from virgin oils or $0.50/gal off if made from recycled oils.

What Kind of Driver Are You?

Driving habits will greatly affect how well a hybrid electric vehicle will perform for you. If you do a lot of commuting and city driving, you'll probably fred a hybrid like the Prius to be an excellent choice, as it was designed to use its electric drive primarily at lower speeds and during stop-and-go driving. Combine that with its regenerative braking system (which charges the traction battery during deceleration) and it's not too difficult to imagine 55- or 60-mpg fuel economy. Those figures, however, can drop noticeably during interstate driving, when the gasoline engine is needed to supplement power; even its relatively small 1.5-liter four-banger will consume a moderate level of fuel at higher speeds. One potential HEV caveat: if you're prone to a heavy foot or tend to get ahead of the pack from the traffic light, driving a hybrid-electric vehicle will not do much to improve your fuel economy. In fact, because of the high-torque characteristics of the electric traction motor, low-end acceleration can be exhilarating, enough to encourage abuse, which is counterproductive. Ford's Escape Hybrid uses a 70-kW (94 horsepower) electric drive to supplement its 2.3-liter gasoline engine, and the Toyota Highlander, a larger SUV, uses three traction motors on its 4WD hybrid models. (Both vehicles are noticeably cleaner, emissions-wise, than their conventional siblings, however).

A Final Word:

Getting rid of your GEO Metro for a Toyota Prius may not be the ecological or economic solution: buying a hybrid when you commute for an hour on the interstate may not be a great choice. Figure out what is best for you and your current situation, as well as the long term and overall picture for the environment. In the end. ride your bike as much as possible and carpool with others, no matter the make and model of the car.