Alternative-fuels: How they compare

As the U.S. looks to decrease its dependence on foreign oil and curb environmental degradation, cleaner-burning gasoline alternatives are getting more attention. While their availability is still limited and their costs can be higher, those obstacles will be lessened as the market grows. The following is a rundown of the most common alternative fuels, compiled with information from the U.S. Department of Energy.

BIODIESEL

Biodiesel was among the first automotive vehicle fuels and is now the fastest growing alternative transportation fuel. Biodiesel is used in conventional diesel engines, primarily in low-level blends of 2, 5, and 20 percent biodiesel with diesel fuel, known as B2, B5, and B20, respectively. Pure mixtures (B100) are also used, though they are less common. Typically, few or no engine modifications are required for blends of up to 20 percent, but modifications may be required in order to use higher percentage blends. According to the World Wide Fuel Charter, a compilation of fuel quality requirements endorsed by the automotive industry, blends of up to 5 percent are safe to use in any diesel engine. But it’s very important that all blends meet quality standards set by the American Society for Testing and Materials (ASTM D6751). You should also you check with your vehicle’s manufacturer before using any biodiesel, as that may void the manufacturer’s warranty.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Vegetable oils, primarily from soybeans; animal fats Vehicle: all diesel models (modifications may be necessary)

Fuel: Click here for station locator
B2-5=$2.81
B20=$2.91
B100=$3.40
Renewable; biodegradable; fewer air pollutant emissions overall vs. conventional diesel engines; domestically produced; improved lubricity in engine vs. conventional diesel Smog causing nitrous oxide emissions may be slightly higher than with gasoline; may congeal at low temperatures; higher blends may damage engine components; may slightly decrease fuel economy; non-renewable fossil fuels are used in its production; lack of widespread fuel availability

Currently no financial incentive for an individual to use.
Click here for laws and incentives

ELECTRIC VEHICLES

Once available as passenger models, electric vehicles (EVs) are now produced only as small neighborhood electric vehicles (NEVs) for everyday drivers. NEVs are compact and designed to travel at low-speeds in neighborhoods and urban areas. All EVs operate with electricity that is stored in a battery that must be recharged. They can either be plugged into an electricity source at home or wherever there is a suitable outlet. While passenger EVs were designed to run for about 80 miles between charges, NEVs will go for about 30 miles, primarily depending on how they are driven, making these vehicles best suited for short-distance travel.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Primarily fossil-fuel powered electricity; also renewable-powered electricity Vehicle: Click here for 2006 models

Fuel: Can be plugged into most standard electrical 110V outlets
n/a Zero tailpipe emissions; widespread recharging options Electricity production is mainly from non-renewable fossil fuel sources Click here for laws and incentives

ETHANOL

Ethanol was one of the first vehicle fuels, and is now the most widely used alternative to gasoline. It’s most commonly used in blends with gasoline, ranging from 5 to 85 percent ethanol content. In fact, you may already be using it, as blends of up to 10 percent (E10) are approved for all gasoline vehicles, and have been used for many years across the nation to improve air quality. Blends above 10 percent require Flexible Fuel Vehicles (FFVs). Millions of FFVs have been sold as standard models by several auto makers, sometimes without the buyer even realizing it. These vehicles can run on either gasoline or ethanol blends. You can check your owner’s manual or with your vehicle’s manufacturer to find out whether your vehicle is an FFV, though you may not be able to find a fueling station nearby. Check with your vehicle’s manufacturer before using blends above 10 percent, as that may void the manufacturer’s warranty.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Primarily corn; also grains or agricultural waste Vehicle: Click here for 2006 models

Fuel: Click here for station locator
$2.41 Renewable; most ethanol-fueled vehicles emit less harmful air pollutants than gasoline-fueled ones; domestically produced Non-renewable fossil fuels are used in its production; slightly decreases fuel economy; lack of widespread fuel availability Click here for laws and incentives

HYBRID ELECTRIC VEHICLES

While not considered an alternative fuel vehicle (AFV) by the government’s definition, hybrid electric vehicles (HEVs) are nonetheless an alternative to conventional gasoline-powered models. An increasing number of passenger vehicles are now available as hybrids. Unlike electric vehicles, HEVs don’t need to be plugged in. Instead the battery is charged by the engine while the vehicle is in use. Consumer Reports’ tests have found that some hybrids get much better fuel economy than conventional vehicles and have excellent reliability. But battery life is unknown, and they do come with higher price tags. To learn more about fuel economy, cost, and overall performance of hybrids, visit our Green Ratings.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Gasoline Vehicle: Click here for 2006 models

Fuel: All gasoline stations
$2.77
(gasoline)
Fewer air pollutant emissions than conventional gasoline engines; widespread fuel availability Good fuel economy with little or no sacrifice in vehicle size and performance. Primarily fueled with non-renewable fossil fuels Click here for laws and incentives

NATURAL GAS

Natural gas is used in two forms to fuel vehicles: compressed (CNG) or liquefied (LNG). CNG is the type used for passenger vehicles, which can run on CNG alone, or have a bi-fueling system that uses both CNG and gasoline. Currently, manufacturers are offering one compact sedan and a variety of pick-up truck models in dedicated CNG, and bi-fueling options. Conventional gasoline engines can also be converted to accept CNG.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Natural gas Vehicle: Click here for 2006 dedicated natural gas models and here for bi-fuel 2006 models

Fuel: Click here for station locator
CNG: $2.12
(per gallon of gas equivalent)
Fewer air pollutant emissions than gasoline engines Non-renewable fossil fuel source; CNG driving range is generally less than comparable gasoline- and diesel-fueled vehicles; lack of widespread fuel availability
Extra tank is required for LNG usurping cargo space.
Click here for laws and incentives

PROPANE

Propane vehicles, on the road since the 1920s, are no longer being manufactured as passenger models. But with refueling facilities in all states, it’s still relatively the most accessible alternative transportation fuel. The most common propane passenger vehicles are those that have been converted from gasoline engines. They can be set up to use propane alone, or have a bi-fueling system that takes either gasoline or propane.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Propane, a fuel derived from petroleum Vehicle: No 2006 models currently available

Fuel: Click here for station locator
$2.56 Fewer air pollutant emissions than gasoline engines Non-renewable fossil fuel energy source; lack of widespread fuel availability Click here for laws and incentives

AND A FUEL FOR THE FUTURE…

HYDROGEN

Fuel-cell vehicles powered with hydrogen are currently under development by virtually every major automaker around the world . The advantage is that hydrogen is widely available and the only tail pipe emission is water vapor. Several exist as demonstration models, but none is available yet for sale to consumers. Consumer Reports recently tested one of these production models–the Honda FCX– and had an initial favorable impression. The testers said that a car like the FCX would be a comfortable, fairly refined option for many commuters, but that high cost of the vehicle, limited availability of hydrogen as well as what it entails to store and transport compressed hydrogen (which in order to be kept at liquid state, has to be refrigerated) were obstacles to be overcome before fuel-cell cars became a real-world option.

Fuel source Availability of vehicle and fuel Cost (2005 national average per gallon) Pros Cons Laws & incentives
Derived from either fossil fuels or renewable energy sources Not yet available to consumers Too early to determine Zero tailpipe emissions Potential use of fossil fuels to produce; high cost of vehicle N/A

You can learn more about alternative transportation fuels from the Department of Energy’s Alternative Fuel Web site.