Transportation accounts for 65 percent of U.S. oil consumption and is the predominant source of air pollution. New transportation technologies are intended to improve the efficiency and emissions of vehicles using petroleum-based fuels, provide cleaner-burning alternative fuels, and reduce the quantity of miles individual vehicles travel on our roads and highways.
What are biofuels?
Biofuels are derived from biological feed stocks (corn, soy, sugarcane, etc.) that are available as renewable sources of fuel.
Biodiesel – a low-polluting diesel alternative made from vegetable oils, animal fats, and even recycled cooking greases.
Ethanol – an alcohol-based fuel derived from crops such as corn, barley, and wheat. Ethanol can be blended with gasoline in varying concentrations. E85, for example, is a blend of 85 percent ethanol and 15 percent gasoline.
Many other alternative fuels are being used today in place of gasoline and diesel fuel, including:
Natural gas – domestically produced and available to end-users through the utility infrastructure. It can either be stored onboard a vehicle as compressed natural gas (CNG) or liquefied natural gas (LNG). Natural gas also can be blended with hydrogen.
Electricity – stored in batteries or produced onboard.
Propane – produced as a by-product of natural gas processing and crude oil refining.
Liquids made from coal – gasoline and diesel fuel that doesn’t come from petroleum.
Alternative fuel vehicles (AFVs) use alternative fuels instead of gasoline or diesel fuel. AFVs range in size and shape, from small commuter cars to large 18-wheeler trucks. A number of automobile manufacturers offer light-duty vehicles for personal transportation.
AFVs are well-suited for fleets in certain “niche” markets. Taxi fleets, for example, with high-mileage vehicles that drive fairly centralized routes, may benefit from using a less expensive alternative fuel such as natural gas or propane. Local delivery fleets-with low mileage, high-use vehicles that frequently idle in traffic or must often start and stop may be good candidates for electric vehicles. Medium- and heavy-duty AFV applications include transit buses, airport shuttles, delivery trucks and vans, school buses, refuse haulers, and street sweepers.
Flex-Fuel Vehicles can be fueled with gasoline or, depending on the vehicle, with either methanol (M85) or ethanol (E85). The vehicles have one tank and can accept any mixture of gasoline and the alternative fuel.
Bifuel or Dual-Fuel Vehicles have two tanks one for gasoline and one for either natural gas or propane, depending on the vehicle. The vehicles can switch between the two fuels.
Dedicated Vehicles are designed to be fueled only with an alternative fuel. Electric vehicles are a special type of dedicated vehicle.
Hybrid Vehicles combine the best features of two different energy sources, one of which is electric power. Until alternative fuels really catch on, hybrids can be a good choice. A hybrid gets about twice the fuel economy as a conventional car of the same size and capacity.
Plug-in Hybrids –known as PHEVs–combine a gasoline or diesel engine with an electric motor and a large rechargeable battery. Unlike conventional hybrids, PHEVS can be plugged-in and recharged from an outlet, allowing them to drive extended distances using just electricity. When the battery is emptied, the conventional engine turns on and the vehicle operates as a conventional, non-plug-in hybrid.) (source: ucsusa.org)
Add Hydrogen and Fuel Cell: Fuel cell vehicles use hydrogen gas to power an electric motor. Unlike conventional vehicles which run on gasoline or diesel, fuel cell cars and trucks combine hydrogen and oxygen to produce electricity, which runs a motor. (source: ucsusa.org)
Alternative fuel stations are becoming increasingly popular across the country, as more consumers and agencies turn to clean fuels. Find out where these stations are using DOE’s Alternative Fueling Station Locator.
The term biomass refers to all the Earth’s vegetation and many products and coproducts that come from it. Biomass is the oldest known source of renewable energy-humans have been using it since we discovered fire-and it has high energy content. The energy content of dry biomass ranges from 7,000 Btus/lb for straws to 8,500 Btus/lb for wood. Domestic biomass resources include agricultural and forestry wastes, municipal solid wastes, industrial wastes, and terrestrial and aquatic crops grown solely for energy purposes, known as energy crops.
Biomass is an attractive energy source for a number of reasons. First, it is a renewable energy source as long as we manage vegetation appropriately. Biomass is also more evenly distributed over the earth’s surface than finite energy sources, and may be exploited using less capital-intensive technologies. It provides the opportunity for local, regional, and national energy self-sufficiency across the globe. And energy derived from biomass does not have the negative environmental impact associated with non-renewable energy sources.
According to the U.S. Department of Energy, “developing a strong biomass industry in the United States will have tremendous economic benefits including trade deficit reduction, job creation, and strengthening of agricultural markets. Growth of the biomass industries can create new markets and employment for farmers and foresters, many of whom currently face economic hardship. Growing biomass energy crops provides new uses for agricultural land currently out of production which can help conserve farm land for future generations. Biomass usage can spur the development of new processing, distribution, and service industries in rural communities. Additionally, using biomass residues rather than disposing of them in landfills can also reduce a major land use problem.”
The map below shows biomass potential for the U.S.