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Climate Change and the Environment

Non-CO2 Tailpipe Emissions

Smog-forming vehicle emissions result from the incomplete combustion of fuels, impurities in fuels and the high-temperature oxidation of atmospheric nitrogen during the fuel-combustion process. Regulated smog-forming tailpipe emissions include hydrocarbons, nitrogen oxides (NOx), carbon monoxide and particulate matter.


In the U.S., smog-forming emissions are regulated by the U.S. Environmental Protection Agency (EPA) under the Clean Air Act as well as by the California Air Resources Board (CARB).

As of 2010, all of Ford’s U.S. vehicles have been certified to the EPA’s Tier 2 regulations, a comprehensive and challenging set of vehicle emissions requirements.

The Tier 2 program, which began with the 2004 model year, coordinates the introduction of cleaner fuels with more stringent vehicle-tailpipe emissions standards to achieve near-zero non-carbon-dioxide (CO2) tailpipe emissions from cars and light trucks. These regulations significantly reduce targeted vehicle emissions, including nitrogen oxides and non-methane organic gases, to help reduce the formation of ozone and particulate matter. The Tier 2 regulations apply to all passenger cars, light trucks and medium-duty passenger vehicles. Ford completed implementing Tier 2 emissions requirements on all relevant vehicles in the 2009 model year.

The Tier 2 program has been highly successful at reducing smog-forming emissions from vehicles and improving urban air quality. The EPA estimates that this program has resulted in reductions in oxides of nitrogen emissions (from all relevant mobile sources) of at least 1.2 million tons as of 2010. Our own studies suggest that the emission reduction benefits of modern vehicles that meet Tier 2 standards will continue to increase as older vehicles that were produced before the Tier 2 standards are replaced by modern vehicles.1

In 2014, the EPA adopted new Tier 3 standards, which are more stringent motor-vehicle emissions standards for future model years. As part of these new standards, the EPA is also requiring reduction of the sulfur levels in gasoline, which will improve the performance of existing catalyst technology in gasoline vehicles and result in reduction of nitrogen oxides, carbon monoxide and volatile organic-compounds emissions from vehicles. The EPA also has stringent emissions standards and requirements for EPA-defined “heavy-duty” vehicles and engines (generally, those vehicles with a gross vehicle weight rating of between 8,500 pounds and 14,000 pounds). These regulations are relevant to Ford’s Super Duty® trucks and some commercial vans. In order to meet the standards for heavy-duty diesel trucks, Ford and most other manufacturers use selective catalytic reduction (SCR) systems, which require periodic customer maintenance. The EPA has issued guidance calling for stringent warning systems and driver inducements to alert motorists to the need for the maintenance of SCR systems.

For the California market, Ford is required to meet the state’s stringent Low Emission Vehicle II (LEV-II) emissions requirements for light-duty vehicles. Under the LEV-II program, manufacturers are effectively required to produce a number of Partial Zero Emission Vehicles (PZEV). A PZEV is a vehicle certified to near-zero emissions standards. Strictly speaking, PZEVs are required to:

  • meet California’s Super Ultra Low Emission Vehicle (SULEV) exhaust emissions standard;
  • produce zero fuel-system evaporative emissions; and
  • be emissions-compliant for a full useful life of 150,000 miles.

For the 2013 and 2014 model year, Ford offered the Focus Electric ZEV, Focus and Fusion PZEV, as well as plug-in hybrid Enhanced Advanced Technology (AT) PZEV versions of the Ford Fusion and C‑MAX. In 2012, CARB finalized revisions to its LEV and ZEV regulations. The new LEV-III Program begins to take effect with the 2015 model year and includes more stringent tailpipe and evaporative emissions standards for light- and medium-duty vehicles, extended durability requirements and changes to the certification test procedures, which will require manufacturers to certify vehicles on fuel containing 10 percent ethanol. The amended ZEV regulations mandate substantial annual increases in the production and sale of battery-electric, fuel-cell and plug-in hybrid vehicles for the 2018–2025 model years. By the 2025 model year, approximately 15 percent of a manufacturer’s total California sales volume will need to be made up of such vehicles. The LEV-III regulations will also require automobile manufacturers to design and develop new emissions after-treatment systems. Compliance with the 2018–2025 ZEV mandate involves intensive planning efforts and large capital investments in order to deliver the required number of advanced-technology vehicles. We are concerned that the market and infrastructure in California might not support the large volumes of advanced-technology vehicles that manufacturers will be required to produce, particularly in the 2018–2025 model years. We also are concerned about potential enforcement of the ZEV mandate in other states that have adopted California’s ZEV program, where the existence of a market for such vehicles is even less certain. We are working with both the EPA and CARB through their regulatory processes to help develop rules that are both effective and feasible. In setting tailpipe emissions regulations, other rules that apply to vehicles – such as fuel economy/greenhouse gas standards and safety standards – must be taken into account to ensure that the total package of requirements is workable.

Ford continues to oppose technology mandates that seek to impose quotas or limits on the production or sale of vehicles with specified powertrain technologies. Regulatory efforts to dictate market outcomes, or to pick technology “winners” and “losers,” are typically unsuccessful and characterized by unintended, unwanted consequences. Manufacturers need the flexibility to build the kinds of vehicles that the marketplace demands based on consumer preferences and other external factors. Emissions standards should be performance based and should be designed to enable manufacturers to introduce vehicles with an array of different technologies.

Information about the emissions performance of all Ford vehicles sold in the U.S. can be found at the EPA’s Green Vehicles site.

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Since 1990, we have decreased the non-CO2 tailpipe emissions from our vehicles sold in Europe by up to 90 percent through the development of a new generation of downsized, high-efficiency gasoline- and diesel-powered vehicles with improved engine technologies and high-tech exhaust gas treatment devices. As part of these emissions-reduction efforts, all of our diesel engines are now fitted with a maintenance-free diesel particulate filter system that requires no additives for filter regeneration.

Further air-quality improvements have been generated as we have introduced vehicles equipped with technology to meet the more stringent Euro 5 emissions standards. We currently offer three variants of our GTDi EcoBoost® engine in Europe: the 1.6 liter, 2.0 liter and the 3-cylinder 1.0 liter. These are among the most technologically advanced engines in production, combining high-pressure direct injection, a low-inertia turbo and twin independent variable cam timing. They join our lineup of high-efficiency common rail diesel engines all complying with Euro 5 emissions levels. In 2012, Ford also launched a new version of the 1.6-liter Ford Duratorq® TDCi engine, featuring the first lean NOx-absorbing technology in a Ford diesel, as well as a completely redesigned common rail injection system to deliver more precise control and increased combustion efficiency. All of our new passenger cars registered as of January 1, 2011, and all light-duty vehicles registered as of January 1, 2012, comply with the Euro 5 standard.

Euro 6 standards have been developed. The initial phase of Euro 6 will be applied beginning in September 2014. The second phase of Euro 6 standards, which will be even more stringent, will be applied beginning in 2017. New test procedures based on consumer driving patterns are also under development by the European Commission and are intended to be finalized during 2013 for use during the implementation of the Euro 6 standards. These new emissions-testing requirements are focused primarily on delivering reduced tailpipe NOx emissions. The European Commission is also developing rules for increasing the severity of the low-temperature testing and evaporative emissions requirements again. The new rules should be finalized during 2013. We are actively engaged with the European Commission and the European member states in developing better regulation.

Even with the significant emissions improvements in modern vehicles, some smog-forming emissions levels remain higher than desired. For example, roadside emissions of NO2 in some locations exceed the stringent European NO2 air quality limits. Ford is working with the European Commission and other stakeholders to define a new emissions test procedure that better measures on-road vehicle emissions for the second stage of Euro 6 regulations. Our own air quality simulations predict a significant improvement in roadside air quality as the existing vehicle fleet is replaced with newer, cleaner vehicles and as emissions regulations become increasingly stringent.

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Emissions Regulations in the U.S. and Europe

Grams per mile

  Nitrogen oxides Hydrocarbons Particulates
Euro 5 (Gasoline) 0.13 0.16 0.08
Euro 5 (Diesel) 0.30 0.08 0.08
U.S. Tier 1 0.60 0.31 NA
U.S. Tier 2 (Bin 5) 0.07 0.09 NA
California LEV II 0.07 0.09 NA
California SULEV 0.02 0.01 NA

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Asia Pacific Africa

Since 2010, our new gasoline-fueled passenger vehicles have been designed to comply with China IV requirements (based on Euro 4 standards). China began implementing more recent European standards (Euro 5) in Beijing in 2013. Korea and Taiwan have adopted very stringent U.S.-based standards for gasoline vehicles and European-based standards for diesel vehicles. Japan, which has unique standards and test procedures, began implementing more stringent standards in 2009. Ford is working to comply with all of these standards using a variety of approaches, including on-board diagnostics and after-treatment technologies.

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South America

New passenger and commercial vehicles in South America must comply with varying levels of U.S.- or European-based emissions regulations. Recently, Brazil, Argentina and Chile have introduced more stringent emissions standards. Brazil approved European Stage 5 (Euro 5) emissions and on-board diagnostic standards for heavy trucks starting in 2012; more stringent light-vehicle limits also came into effect starting in 2012. Argentina also will apply Euro 5 standards beginning in 2015 (for new vehicle homologations) and 2017 (for new vehicle registrations). Chile approved a plan to introduce more stringent emissions standards (i.e., Euro 4 and 5 or corresponding U.S. emissions standards) nationwide for light- and medium-duty vehicles, and progressive alignment with the Metropolitan Region (i.e., the capital city Santiago and surrounding area) by September 2014. Heavy-duty vehicles will be required to meet Euro 5 (or corresponding U.S. emissions standards) by October 2014. As a consequence, the following non-CO2 emissions-control technologies have been or will be introduced on our vehicles sold in South America: on-board diagnostic systems in Brazil and Argentina (which are being studied for use in Chile); particulate filter technology for some diesel products; and selective catalytic-reduction systems for heavy diesels in all three countries.

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  1. T.J. Wallington, J.A. Anderson, S.E. Winkler, “Comment on ‘Natural and Anthropogenic Ethanol Sources in North America and Potential Atmospheric Impacts of Ethanol Fuel Use’”, Environ. Sci. Technol. 47, 2139−2140 (2013).