Smart Buying Essentials

Alternative Fuel and Hybrid Vehicle Guide

Including:

• Hybrid Electric Vehicles
• Battery-Powered Electric Vehicles
• Fuel Cell Vehicles
• Ethanol/Methanol Vehicles
• Natural Gas Vehicles
• Propane Vehicles

There's a lot to be said for the sound and feel of a high-revving engine accompanied by a few choice power shifts - or for that matter the visceral thrill of ten cylinders motivating a scorching straight-line launch. We may still experience this decades into the future. But after more than 100 years with internal combustion and gasoline, it's apparent that things are changing.

Within the next decade or two, there's a good chance you'll be driving a vehicle powered by an advanced power plant that's far removed from the familiar internal combustion engine now residing under your hood. Government regulation, environmental pressures, Middle East instability and market competition have spurred accelerated research and development into alternative fuels and the vehicles that run on them, creating a new twist in the motor vehicle's evolution.

Many alternative fuel buyers are motivated by such tangibles as fewer tailpipe emissions and significantly higher fuel economy, the latter resulting in decreased annual fuel costs. Other financial incentives are sometimes available from air pollution control agencies, state energy offices and other state and local sources. Additionally, non-financial incentives, such as the ability to drive in carpool lanes with a single occupant, are available in several states.

Let's examine the various alternative fuels and advanced technologies driving this part of the automotive field to see where we are and where we're headed.

Hybrid Electric Vehicles

Hybrid vehicles combine an electric motor with an internal combustion engine. The hybrid's key distinct advantages are the utilization of the established fueling infrastructure, reduced emissions and extremely high fuel economy - up to 48mpg highway and 51 mpg city. Some hybrids drive exclusively using electric power during slower speeds, an internal combustion engine at higher speeds, and both power plants under certain driving conditions. Others use an extremely efficient internal combustion engine at all times with electric motor boost as needed. In both configurations the internal combustion engine extends the driving range, eliminating a critical limitation with pure battery electric vehicles.

Currently there are significant numbers of gasoline-electric hybrid vehicles on the road. Some hybrids use smaller-than-normal, highly efficient three- or four-cylinder internal combustion engines, combining with electric motors to add the levels of power required for a satisfying driving experience. Larger V-6 and V-8 hybrids are an interesting deviation from this scenario as these hybrid options provide higher levels of performance than their internal combustion variants.

Another hybrid variant is the "mild" parallel hybrid. Mild hybrids use a simpler system that employs engine stop and start, resulting in more modest fuel economy gains in the 8-10% range.

Battery-Powered Electric Vehicles

Thanks to the limited electric vehicle test-marketing undertaken by automakers during the latter part of the 1990s, battery electric vehicles are on American highways today. Their advantages are numerous, including no harmful emissions, little required maintenance and lower operating costs.

Battery-powered electric vehicles have well-defined drawbacks. They are expensive, generally priced from $30,000 to $50,000. Battery electric vehicles also have a limited range of no more than 100 miles - and often far less - before requiring a lengthy recharge, which can take as much as 20 hours. Additionally, they may require expensive battery replacement after a number of years.

Fuel Cell Vehicles

Even as auto manufacturers develop their array of hybrid, alternative fuel and highly efficient gasoline vehicles, there's a growing belief that the most viable longer-term alternative fuel for mass production may be hydrogen, with its most logical application being the hydrogen fuel cell.

A fuel cell is an electrochemical power plant fueled by hydrogen that creates electricity for driving a vehicle's electric drive motors. Its great advantage is that it's more than twice as efficient as an internal combustion engine in transforming energy into power - and that it does this without combustion. Its sole emissions are heat and water vapor, with no greenhouse gases produced.

In recent years some automakers have been examining hydrogen as a fuel for their internal combustion engine vehicles, as well as for fuel cells. Hydrogen vehicles have quite a developmental road ahead of them, so don't expect to see them on the highways in large numbers for some years. Fuel cells still face significant developmental issues that include durability and cost. Operation in extremely cold temperatures is also a hurdle.

Perhaps the greatest challenge for hydrogen vehicles is that of infrastructure. Simply put, there are only a handful of places in the country where hydrogen vehicles can be fueled. A hydrogen refueling station is extremely expensive, making the creation of a widespread refueling infrastructure a daunting task.

Ethanol/Methanol Vehicles

Two types of alcohol, ethanol and methanol, are used as alternative fuels in flexible fuel vehicles (FFVs), whose gasoline engines have undergone minor modifications. A high-octane renewable liquid fuel, ethanol is made from corn or other grains, or even from biomass waste. Methanol, a liquid fuel made most often from natural gas (though sometimes from coal or biomass), produces about half the smog-forming emissions of gasoline in a comparable vehicle. Both of these alcohol fuels contain less energy content than gasoline, a situation that results in a shorter driving range. However, manufacturers often equip their FFVs with larger fuel tanks to offset this.

As motor fuels, ethanol and methanol typically are mixed with 15 percent gasoline, creating M85 and E85. The addition of this relatively small percentage of gasoline overcomes cold-starting issues faced by alcohol and also enhances safety, since 100 percent alcohol burns with an invisible flame. The addition of gasoline remedies this danger.

Both ethanol and methanol have been used in FFVs, which are equipped to run on any mixture of alcohol fuel and gasoline in the same tank. However, while M85 FFVs were popular in the mid-1990s and manufactured in small numbers by nearly a dozen automakers, these have fallen by the wayside as interest in methanol diminished. Now, a growing number of E85 FFV models are being offered by select automakers.

You'll find E85 vehicles offered in the most popular segments, from pickups and SUVs to sedans and minivans. It should be noted that these models are available as FFVs only with certain engines.

It's estimated that more than two million E85 FFVs are on U.S. roads. Offsetting this is that there are less than 3,000 ethanol fueling stations in the country, which means most of these vehicles are running on gasoline. That could change in a big way if attention is paid to expanding the ethanol refueling infrastructure and making best use of the alternative fuel vehicles already on the highway.

Natural Gas Vehicles

Of all the alternative fuels used in cars and trucks, natural gas - either compressed natural gas (CNG) or liquefied natural gas (LNG) - offers the biggest cut in emissions compared to gasoline. Typically, CNG is used in light- and medium-duty vehicles while LNG is available only for commercial customers in heavy-duty vehicle applications.

The driving range of a natural gas vehicle depends on engine displacement, vehicle mass, fuel economy, and of course on driving habits. Overall, a dedicated natural gas vehicle running only on CNG offers a substantially shorter driving range than its gasoline counterpart - typically 120 to 200 miles. It's simply not possible to package enough bulky gaseous fuel cylinders onboard a vehicle to store the same amount of energy as in a conventional gasoline tank. This storage issue finds cylinders located beneath a vehicle and sometimes in a sedan's trunk, just behind the rear seatback, which sacrifices some cargo space.

Bi-fuel vehicles resolve the range issue by storing both gaseous fuel and gasoline onboard, thus allowing a vehicle to run on either. Of course, running on gasoline doesn't achieve the same emissions reductions as natural gas, so the goal is to run on CNG whenever possible and gasoline only as necessary.

While much greater energy can be stored onboard a vehicle in LNG form and thus a greater driving range can be provided, this liquid fuel must be stored and dispensed at -260 degrees F, which presents safety and handling issues that relegate it to commercial use only.

CNG is available at nearly 200 natural gas fueling stations in California, with more than half offering full or limited public access, and less than 1,000 stations nationwide. They include facilities at some gasoline service stations under contract with gas utility companies. While this may seem a large number, it pales in comparison to the over 100,000 gasoline stations conveniently located across the country.

Natural-gas vehicles typically cost about $4,000 to $5,000 more than gasoline-powered models.

Propane Vehicles

Also known as LPG or liquefied petroleum gas, propane is the third most prevalent transportation fuel, behind gasoline and diesel. Propane is used in thousands of fleet vehicle operations around the world including taxis, police cars, school buses and trucks. Some light-duty vehicles are designed to run exclusively on propane while others are dual-fuel models that can operate on either propane or gasoline.

Summary

As we've presented, the sorting-out process for alternative fuels is well underway. Some, like methanol, have already fallen by the wayside while others such as E85 have stalled. Hybrid and all-electric vehicles promise a continuing rise to stardom while hydrogen fuel cell vehicles may one day be feasible. Clearly there is no single-solution "silver bullet," as each of the alternatives has limitations and challenges. Technology, infrastructure, legislation and consumer demand will determine the powertrains and fuels of the future.