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Fuels and Engines

Fuels and Engines

Emissions from engines -- both those used in highway vehicles and those used for other purposes -- can be harmful to human health and to the environment. EPA's new standards for engines and fuels offer a flexible approach to reducing these emissions without undue cost to industry or consumers. In addition to reducing the hazards of these traditional fuels, EPA is actively encouraging the use of alternative "clean fuels."

Related topics
Vehicle and Equipment Maintenance and Repair
Tanks and Containment
Spill Prevention, Control, and Countermeasures (SPCC) Program

Related publications from the Ag Center
Fuels and Engines

Related laws
Clean Air Act

Related environmental requirements
Clean Air Act
Air Regulations 40 CFR Parts 50 - 97

More information from EPA
Office of Transportation and Air Quality (formerly Office of Mobile Sources)
Nonroad Engines
Highway Vehicles 

Alternative, Renewable, or "Clean" Fuels

The most familiar transportation fuels in this country are gasoline and diesel fuel, but any number of energy sources are capable of powering motor vehicles. These include alcohols, electricity, natural gas, and propane. Some vehicle fuels, because of physical or chemical properties, create less pollution than do today's gasolines. These are called "clean fuels."

Use of clean fuels could also help slow atmospheric buildup of carbon dioxide, a "greenhouse gas" that contributes to the potential for global warming. Combustion of any carbon-based fuel produces carbon dioxide. But the overall impact of a given fuel on global warming depends on how the fuel is made. In general, fuels produced from biomass (crops, trees, etc.) and from natural gas result in less carbon dioxide accumulation than fuels made from petroleum or coal. Clean fuels have benefits that reach beyond their air quality advantages. New fuels in the marketplace give consumers new choices and could decrease U.S. dependence on imported oil.

Renewable fuels are produced from plant or animal products or wastes, rather than from fossil fuels. The best known renewable fuels are ethanol and biodiesel. Congress directed EPA in the Energy Policy Act of 2005 to design a program that requires the blending of renewable fuels into our nation’s motor-vehicle fuel supply. This program is called the Renewable Fuel Standard (RFS). The RFS program requires increasing the use of renewable fuels every year through 2012. After 2012, renewable fuel use is required to grow in volume as gasoline demand grows.

More information from EPA
Alternative Fuels
Climate Change - What You Can Do - On the Road
Green Vehicle Guide
Renewable Fuel Standard Program
March 26, 2010 News Release: Changes to Renewable Fuel Standard Program
EPA Region 7 Environmental Laws Applicable to Construction and Operation of Ethanol Plants (PDF) (104 pp, 3.1MB)

More information from USDA
Southern Sustainable Agriculture Research and Education (SARE)'s Biofuel and Energy Position Paper Exit EPA
User-friendly Environmental Manual for Biodiesel Facilities from Region 7

Success Stories
EPA Awards Two Colorado Small Businesses $210,000 in Innovation Research Contracts

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EPA National Clean Diesel Campaign

Reducing emissions from diesel engines is one of the most important air quality challenges facing the country. Even with more stringent heavy-duty highway engine standards set to take effect over the next decade, over the next twenty years, millions of diesel engines already in use will continue to emit large amounts of nitrogen oxides and particulate matter, both of which contribute to serious public health problems. These problems are manifested by thousands of instances of premature mortality, hundreds of thousands of asthma attacks, millions of lost work days, and numerous other health impacts.

Building on the successes of EPA’s regulatory and voluntary efforts to reduce emissions from diesel engines, EPA has created the National Clean Diesel Campaign (NCDC). The Campaign will work aggressively to reduce the pollution emitted from diesel engines across the country through the implementation of varied control strategies and the aggressive involvement of national, state, and local partners.

Agriculture Sector
The agricultural initiative will partner with the farming community, governmental organizations, and NGOs to promote clean diesel strategies including bio/renewable fuels across the country.

Clean Agriculture USA
Clean Agriculture USA, part of the National Clean Diesel Campaign (NCDC), is an incentive-based, innovative program designed to help reduce diesel emissions from existing diesel engines and nonroad agricultural equipment. Nonroad diesel engines can contribute significantly to the levels of particulate matter (PM) and nitrogen oxides (NOx) in the air. In recent years, EPA has set emission standards for engines used in most new agricultural equipment. However, since such equipment can last 25 to 30 years or more, it could take many years before existing equipment is replaced with newer, cleaner equipment. Because EPA's regulations only apply to newly manufactured diesel engines, EPA developed the Clean Agriculture USA program to help farmers, ranchers, and agribusinesses reduce emissions from older engines that are in operation today.

More information about the National Clean Diesel Campaign
West Coast Collaborative Agriculture Workgroup Exit EPA - the Collaborative is part of EPA’s National Clean Diesel Campaign. The Agriculture Workgroup is exploring opportunities to share information and seek funding in California, Oregon, Washington, Alaska, Arizona, Idaho, Nevada, Hawaii, Canada, and Mexico.
Midwest Clean Diesel Initiative (MCDI) - active in promoting voluntary diesel reductions specifically concentrating on the reduction of agricultural related emissions in Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin.
Northeast Diesel Collaborative Exit EPA - the Collaborative combines the expertise of public and private partners in a coordinated regional initiative to significantly reduce diesel emissions and improve public health in Maine, New York, New Jersey, Connecticut, New Hampshire, Rhode Island, Massachusetts, and Vermont.
Blue Skyways Collaborative Exit EPA - the Collaborative was created to encourage voluntary air emissions reduction in Minnesota, Iowa, Nebraska, Missouri, Kansas, Arkansas, Oklahoma, Louisiana, Texas, and New Mexico, and the area along the borders with Canada and Mexico.
Southeast Diesel Collaborative Exit EPA - the Collaborative is a voluntary, public-private partnership involving leaders from federal, state and local government, the private sector, and other stakeholders in Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, and Tennessee.
Rocky Mountain Clean Diesel Collaborative - the Collaborative is a partnership between EPA Region 8, Denver Regional Air Quality Council (RAQC), Colorado Department of Public Health and the Environment (CDPHE), and Denver Department of Environmental Health.
Mid-Atlantic Diesel Collaborative Exit EPA - the Collaborative is a partnership between leaders from federal, state, and local government, the private sector, and environmental groups in Delaware, Maryland, Virginia, Pennsylvania, West Virginia, and the District of Columbia.
California Biomass Collaborative Exit EPA - the mission of the Collaborative is to enhance the sustainable management and development of biomass in California.

More information from EPA
EPA's National Clean Diesel Campaign
Grants and Funding

Success Stories
Tennessee Department of Transportation and the Tennessee Diesel Working Group National Leadership Award
New Technology Featured at Annual California Biomass Collaborative and the West Coast Collaborative
First of EPA's $50 Million Clean Diesel Funding Awarded
EPA Releases Report to Congress: The Clean Diesel Program Protects Health and the Environment

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Heavy-Duty Engine and Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements

EPA has established a comprehensive national control program that will regulate the heavy-duty vehicle and its fuel as a single system. As part of this program, new emission standards will begin to take effect in model year 2007 and will apply to heavy-duty highway engines and vehicles. These standards are based on the use of high-efficiency catalytic exhaust emission control devices or comparably effective advanced technologies.

Because these devices are damaged by sulfur, EPA is also reducing the level of sulfur in highway diesel fuel by 97 percent by mid-2006. The program provides substantial flexibility for refiners, especially small refiners, and for manufacturers of engines and vehicles, to aid them in implementing the new requirements in the
most cost-efficient manner.

More information from EPA
Heavy-Duty Highway Diesel Program

Clean Diesel Trucks, Buses, and Diesel Fuel
Regulations and Standards

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Nonroad Engines and Air Pollution

Most nonroad equipment and vehicles are powered by engines that burn gasoline or diesel fuel. Pollution from these engines comes from byproducts of the combustion process (exhaust) and, for gasoline-fueled engines, from evaporation of the fuel itself.

Electric equipment is cleaner than equipment powered by gasoline engines. Electrically powered lawn and garden tools produce essentially no pollution from exhaust emissions or from fuel evaporation. However, even electric equipment is not pollution-free, because power plants that generate the electricity do pollute.

Emission control for nonroad engines has not been a major design consideration until now because of their relatively lower overall contribution to air pollution. Consequently, these engines are much less clean than highway vehicles, which have been subject to regulatory controls for more than 20 years. Emissions from nonroad engines contribute as much as 15 to 20 percent of unhealthy pollution in cities across the United States.

What Is a Nonroad Engine? "Nonroad" is a relatively new term that covers a diverse collection of engines, equipment, and vehicles. Also referred to as "off-road" or "off-highway," the nonroad category includes outdoor power equipment, recreational vehicles, farm and construction equipment, boats, and locomotives.

Pollutants From Nonroad Engines -- Pollutants from nonroad sources include:

Controlling Nonroad Emissions -- The 1990 Clean Air Act specifically directs the U.S. Environmental Protection Agency (EPA) to study, and regulate if warranted, the contribution of nonroad engines to urban air pollution. A 1991 EPA study documented higher than expected emission levels across a broad spectrum of engines and equipment. Emission reductions are being sought from the following engine types:

EPA is working together with all stakeholders on a comprehensive strategy to reduce these emissions. One part of that strategy is a public information program to show consumers how to prevent pollution from nonroad engines by reducing gasoline spillage and choosing clean equipment. Another part of the strategy will establish a regulatory process that sets emission standards for several categories of nonroad engines.

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Reducing Nonroad Diesel Emissions

Nonroad diesel engines contribute greatly to air pollution in many of our nation's cities and towns. In recent years, EPA has set emission standards for the engines used in most construction, agricultural, and industrial equipment. EPA has also adopted nonroad diesel fuel requirements to decrease the allowable levels of sulfur, which can damage advanced emission control technologies. The most recent nonroad engine and fuel regulations complement similarly stringent regulations for diesel highway trucks and buses and highway diesel fuel for 2007.

In May 2004, as part of its Clean Diesel Programs, EPA finalized a comprehensive rule to reduce emissions from nonroad diesel engines by integrating engine and fuel controls as a system to gain the greatest emission reductions. The new engine standards will reduce PM and NOx emissions by 90 percent. Closely linked to these engine provisions are new fuel requirements that will decrease the allowable levels of sulfur in fuel used in nonroad diesel engines, locomotives, and marine vessels by more than 99 percent. These fuel improvements will create immediate and significant environmental and public health benefits by reducing PM from engines in the existing fleet of nonroad equipment. It also makes it possible for engine manufacturers to use advanced emission control technologies, similar to those upcoming for highway diesel trucks and buses. These reductions in NOx and PM emissions from nonroad diesel engines will provide enormous public health benefits. EPA estimates that by 2030, controlling these emissions will annually prevent 12,000 premature deaths, 8,900 hospitalizations, and one million work days lost. The overall benefits ($80 billion annually) of this rule outweigh the costs by a ratio of 40 to 1. This final rule is one of a suite of inter-related rules known as the Clean Air Rules of 2004 which address ozone and fine particle pollution, nonroad diesel emissions, and power plant emissions of sulfur dioxide, nitrogen oxides and mercury.

More Information About the Nonroad Diesel Emissions Program
Nonroad Diesel Emissions

Related environmental requirements 
Clean Air Act
Control of Emissions of Air Pollution From Nonroad Diesel Engines (40 CFR Parts 86 and 89)

More information from EPA
Nonroad Engines, Equpiment, and Vehicles
EPA Releases Final Rule on Emissions From Nonroad Spark-Ignition Engines, Equipment
EPA Testing Shows Nonroad Diesel Equipment Meets Tough New Pollution Limits

Contact EPA
EPA Nonroad Vehicles and Engines Contacts

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SmartWaySM Transport Partnership

The SmartWaySM Transport Partnership is a voluntary collaboration between U.S. EPA and the freight industry designed to increase energy efficiency while significantly reducing greenhouse gases and air pollution. SmartWay Transport Partners lead the way towards a cleaner, more efficient transportation future by adopting fuel-saving strategies that increase profits and reduce emissions -- a "win-win" opportunity for all.

By 2012, the SmartWay Transport initiative aims to reduce between 33 - 66 million metric tons of carbon dioxide (CO2) emissions and up to 200,000 tons of nitrogen oxide (NOx) emissions per year. At the same time, the initiative will result in fuel savings of up to 150 million barrels of oil annually. There are three primary components of the program: creating partnerships, reducing all unnecessary engine idling, and increasing the efficiency and use of rail and intermodal operations.

More information from EPA
SmartWay Transport Web site
SmartWay Transport - Publications

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Waste To Biogas Mapping Tool

The Waste to Biogas Mapping Tool is an interactive map created to connect organic waste producers (e.g. grease rendering facilities or food processing facilities) and potential users (e.g. wastewater treatment facilities) for the purpose of biogas production through co-digestion. Co-digestion is the addition of high strength wastes such as food scraps and fats, oils, and grease (FOG) to a wastewater treatment plant or dairy digester. Co-digesting organic waste materials allows facilities to save and make money while reducing greenhouse gas emissions, providing a renewable energy source, and diverting valuable resources from landfills and/or sewer pipes.

More information from EPA
Biogas Mapping Tool
Biogas Mapping Tool FAQ
Biogas Mapping Tool Updates

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