are alternative fuels (AFs)?
U.S. Department of Energy: Alternative
fuels are substantially non-petroleum and yield energy security
and environmental benefits. DOE currently recognizes the following
as alternative fuels: methanol and denatured ethanol as alcohol
fuels (alcohol mixtures that contain no less than 70% of the
alcohol fuel), natural gas (compressed or liquefied), liquefied
petroleum gas, hydrogen, coal-derived liquid fuels, fuels derived
from biological materials, and electricity (including solar energy).
DOE can expand this list when new fuels are developed and approved
as meeting this definition.
Natural Gas CNG
- Liquefied Natural
To learn More about alternative
Type of Alternative
- Biodiesel Vehicles
- Electric Vehicles
- Ethanol Vehicles
- Natural Gas Vehicles (NGVs)
- Bi-Fuels NGVs
- Propane Vehicles
To learn more about alternative
fuel vehicles click
Fuel Vehicles Suppliers
Resources and Related
Biodiesel is a lot like diesel fuel, but made from vegetable oil or animal fat,
this is a renewable resource. Biodiesel is not regular vegetable oil and
is not safe to swallow. Biodiesel is biodegradable though, so it is much
less harmful to the environment if spilled. Biodiesel is made through a process
called transesterification. This process makes vegetable oil and animal fat
into esterified oil, which can be used as diesel fuel, or mixed with regular
Biodiesel can be used as
a pure fuel or blended with petroleum in any percentage. B20 (a blend of
20 percent by volume biodiesel with 80 percent by volume petroleum diesel),
B2, and B5 are common fuel blends used today.
Natural Gas (CNG)
Compressed Natural gas is a common fuel and comes from underground.
It is a gas much like air rather than a liquid like oil (petroleum). It has been
found to be environmentally friendly and its popularity is growing. Natural Gas
is made up mostly of methane the other 5 percent is made up of various gases
along with small amounts of water vapor. These other gases include butane, propane,
ethane and other trace gases. Methane is a hydrocarbon, meaning its molecules
are made up of hydrogen and carbon atoms. Its simple, one carbon, molecular structure
(CH4) makes possible its nearly complete combustion.
Electricity can also be used to fuel vehicles.
Electric Vehicles don't burn gasoline in an engine. They use
electricity stored on the
12 or 24 batteries, or more, are needed to power the car.
Just like a remote-controlled, model electric car, EV's have
motor that turns the wheels and a battery to run that motor.
Ethanol also known as grain alcohol is generally
made in the United States from corn. It can also be
made from organic materials or biomass, which includes
agricultural crops and waste,
material left from logging, and trash including cellulose.
Brazil, which is by far the largest producer in the world, makes
ethanol from sugar cane. Projects are now underway in California
to convert some of the state's agricultural waste, like rice
straw that is now burned in fields, into ethanol.
Hydrogen is number one on the periodic
chart of elements and the lightest of all elements.
It is easy to produce
through electrolysis, simply splitting water (H20) into oxygen
and hydrogen by using electricity. Hydrogen burns nearly
pollution-free. When burned, it turns into heat
and water vapor. When burned in an internal combustion engine,
the combustion also produces small amounts of other gases.
These other gases are
mostly oxides of nitrogen because the hydrogen is being burned
with air, which is about two-thirds nitrogen. Being a non-carbon
fuel, the exhaust is free of carbon dioxide.
Natural Gas (LNG)
LNG is made by refrigerating natural gas to condense
it into a liquid. Liquefied natural gas is made by refrigerating
natural gas to minus 260 degrees Fahrenheit (260 degrees below
zero) to condense it into a liquid. This is called liquefaction.
The liquefaction process removes most of the water vapor, butane,
propane, and other trace gases, that are usually included in ordinary
natural gas. The resulting LNG is usually more than 98 percent
Petroleum Gas (LPG)
Liquefied petroleum gas is also know as propane, this is
because LPG is mostly made up of propane. Actually, LPG
is made of a mixture of propane and other
similar types of hydrocarbon gases. Different batches of LPG have slightly
different amounts of the different kinds of hydrocarbon molecules. These hydrocarbons
are gases at room temperature, but turn to liquid when they are compressed.
LPG is stored in special tanks that keep it under pressure, so it stays a liquid.
The pressure of these tanks is usually about 200 pounds per square inch (abbreviated "psi").
also know as wood alcohol, can be made from
various biomass resources like wood, as well as from coal.
However, today nearly all methanol is made from natural gas,
it is cheaper. Methanol
must not be confused with ethanol.
Biodiesel blends are being used in a
number of heavy-duty vehicles throughout the country. The
blend of biodiesel
is B20 (20% biodiesel / 80% diesel), but B100 (neat biodiesel)
and blends of less than 20% biodiesel can also be used.
In an Electric Vehicle, batteries and other energy storage devices
are used to store the electricity that powers the electric motor
vehicle. EV batteries must be replenished by plugging in the
vehicle to a power source. Some EVs have on-board chargers; others
plug into a charger located outside the vehicle, but both must
use electricity that comes from the power grid to replenish the
battery. Although electricity production may contribute to air
pollution, an EV is a zero emission vehicle and its motor produces
no exhaust or emissions.
Ethanol vehicles are manufactured to be
capable of running on up to 85% denatured ethanol, 15% gasoline
or any mixture of the two up to the 85% ethanol limit. Vehicles
manufactured for E85 use are commonly called flexible fuel vehicles
Hydrogen fuel cell vehicles are not yet commercially available.
However, they are currently being demonstrated in light- and
heavy-duty applications in fleets throughout the country. Although
they are still in development, hydrogen vehicles represent an attractive
option for reducing petroleum consumption and improving air quality.
Hydrogen vehicles are powered by fuel cells that produce no air
pollutants and few greenhouse gases. If fueled with pure hydrogen,
fuel cells emit only heat and water as a byproduct.
Natural Gas Vehicles (NGVs)
Natural Gas Vehicles run on Compressed natural gas or Liquefied
Natural Gas. Natural gas is one of the cleanest burning alternative
fuels available and offers a number of advantages over gasoline.
In light-duty applications, air exhaust emissions from natural
gas vehicles are much lower than those from gasoline-powered
vehicles. In addition, smog-producing gases, such as carbon
monoxide and nitrogen oxides, are reduced by more than 90%
and 60%, respectively and carbon dioxide, a greenhouse gas,
is reduced by 30%-40%.
Bi-fuel NGVs have two separate fueling systems that enable the
vehicle to use either natural gas or a conventional fuel (gasoline
Vehicles fueled with hydrogen/natural gas blends (HCNG) are an initial step toward
the hydrogen-based transportation of the future. HCNG vehicles offer the potential
for immediate emissions benefits, such as a reduction in nitrogen oxides (NOx)
emissions. At the same time, they can pave the way for a transition to fuel cell
vehicles by building early demand for hydrogen infrastructure.
Propane, also known as liquefied petroleum gas (LPG), has been
used in vehicles since the 1920s. Propane is the most accessible
of the liquid and gaseous alternative fuels. All states have
publicly accessible fueling stations. These include cars, pickup
trucks, and vans; and medium- heavy-duty vehicles such as shuttles,
trolleys, delivery trucks, and school
buses; and off-road vehicles such as forklifts and loaders. Propane
vehicles can be equipped with dedicated fueling systems designed
to use only propane, or bi-fuel fueling systems that enable fueling
with either propane or gasoline.