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Ethanol Flexible Fuel Vehicle Conversions

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Rising gasoline prices and concerns about climate change have greatly increased public interest in ethanol use. Vehicle manufacturers currently offer ethanol flex-fuel vehicles (FFVs) in a wide variety of makes and models at little or no extra cost. In spite of the availability of new and used FFVs, many consumers are curious about the prospects for converting their existing gasoline vehicles to operate on ethanol.

Background

The Environmental Protection Agency (EPA) implements regulations under the Clean Air Act that require certification of new vehicles as being compliant with emissions requirements (see the Code of Federal Regulations, Title 40, Parts 85 and 86). Certification is granted to the manufacturer for specific vehicle configurations operating on specific fuels according to an established test protocol. Installing or modifying a fuel system to allow a vehicle to operate on a fuel other than that for which it was originally certified is considered tampering—a violation of federal regulations that carries a significant fine.

EPA does have a process by which manufacturers of conversion systems can obtain a Certificate of Conformity for converted vehicles. In recent years, manufacturers of natural gas, propane and FFV (E85) conversions have used this process to certify several vehicles for operation on these fuels. This process certifies the converted vehicle—not the conversion system by itself.

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Regulatory Requirements

Regulations requiring aftermarket fuel converters to certify their conversions are found in 40 CFR Parts 85 and 86. Conversion systems are not considered to be a type of "device," as has been suggested by some manufacturers, which might otherwise allow converters to sell their systems without obtaining EPA certificates. This situation is sometimes the case with devices such as high-performance air filters, free-flow mufflers and exhaust systems, and some other aftermarket accessories. Because of the complexity of certifying an ethanol FFV, including meeting EPA's on-board diagnostics (OBD) requirements, EPA works with each company interested in certifying an ethanol FFV conversion system.

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Certification Process Overview

Certification of fuel conversions closely follows the process original equipment manufacturers (OEMs) use when certifying new model year vehicles. For new vehicles, EPA issues certificates for specific vehicle groupings, called an engine family or test group. A test group, designated by the OEM, contains vehicles with common design elements (such as the number of cylinders or a specific engine and transmission configuration) and similar emission components (such as a similar size catalyst and precious metal loading). There are many test groups for a particular OEM for a given model year, and there are often different test groups for what might appear to be the same kind of vehicle. For example, a pickup truck may be available with either two-wheel or four-wheel drive or with different engine and transmission combinations, each of which might require a separate series of tests and individual Certificates of Conformity.

The process for ethanol conversions takes a similar approach. Each test group of a specific vehicle type with a specific conversion system is tested and considered for certification. The tests ensure that the converted vehicle meets emission standards when operated on any blend of ethanol and gasoline, from 0 percent ethanol to 85 percent ethanol (E85), for the full useful life of the vehicle. It also ensures that the OEM's gasoline vehicle components and materials will be compatible with E85 throughout the life of the vehicle.

There is no "one size fits all" category or universal EPA certificate for a conversion system that would allow it to be legally installed on any vehicle type or engine configuration. How the specific fuel and emission control systems work together determines compliance with EPA emission standards for a particular vehicle.

If a company wants to sell conversion systems in California, similar certification procedures must be followed to obtain approval from the California Air Resources Board (CARB).

Emission Standards

Emission standards are fuel neutral, which means that the same emission requirements apply no matter the fuel type. Therefore, to prove compliance with emissions standards, converted vehicles must demonstrate they meet emission standards when using the alternative fuel. For ethanol conversions, conversion companies must prove emissions compliance with exhaust standards when vehicles are operating on gasoline as well as E85.

OBD Approval Letter

A vehicle's on-board diagnostic (OBD) system performs constant checks to ensure that all emissions-related components operate correctly. The OBD system notifies drivers of any issues or problems by illuminating a malfunction indicator light on the dashboard (sometimes called the check-engine light). Meeting EPA OBD requirements is a fundamental part of the certification process, and these requirements are described in detail in EPA's certification regulations.

Obtaining an OBD approval letter from EPA is just one step in the overall certification process and is not by itself an approval from EPA for the sale of conversion systems. The approval letter only documents that EPA has reviewed the operation of the fuel-converted vehicle's OBD system, including any necessary supporting data, and finds that it meets EPA's OBD regulatory requirements.

Fuel conversions sold in California must receive an OBD approval from CARB.

Certification Steps

  1. The FFV conversion company and EPA meet to lay out the process for certifying one or more vehicle test groups.
  2. EPA supplies references to guidance documents and assists the converter in obtaining an example Application for Certification from a fuel converter and the Application for Certification for the OEM test group that the converter desires to convert to an ethanol FFV. This provides both a sample of the required application, plus baseline data on the vehicle test group that's being converted.
  3. The conversion company initiates the appropriate emissions testing on gasoline as well as ethanol test fuels at an emissions laboratory that can perform standard EPA tests.
  4. The conversion company evaluates OBD system impacts and submits a description of the OBD system and proof of compliance with EPA's OBD regulatory requirements.
  5. Upon acceptance, EPA issues an OBD approval letter. This letter becomes an integral component of the Application for Certification. (See the OBD Approval Letter section for details.)
  6. The conversion company submits to EPA comprehensive emissions testing data as part of the complete Application for Certification (for a Certificate of Conformity for the specific test group to be fuel converted).
  7. EPA may require confirmatory emissions testing at its laboratory in Ann Arbor, Michigan.
  8. EPA reviews the application to ensure that all requirements are met before issuing a Certificate of Conformity.

As mentioned previously, a similar process is required by CARB to obtain an Executive Order (the CARB equivalent of an EPA certificate) for sales in California.


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Status of Ethanol Conversion Certifications

To date, the following ethanol conversions have been approved by the EPA, through a Certificate of Conformity.

Vehicle Model Year Vehicle Make Vehicle Model Engine Size (L) Test Group Conversion Company Date of Certification
2006* Chrysler/Dodge 300/SRT-8, 300AWD, Magnum, Magnum AWD, Charger 5.7/6.1 6CRXV05.7VE0 Flex Fuel US, LLC May 14, 2008
2005* Chrysler/Dodge 300/SRT-8, 300AWD, Magnum, Magnum AWD, Charger 5.7/6.1 6CRXV05.7VHO Flex Fuel US, LLC June 24, 2008

*Note: This certificate does not cover vehicles that operate in California and may not cover vehicles in other states that have adopted and placed into effect California emissions standards.

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Resources

Some of the following documents are available as Adobe PDFs. Download Adobe Reader.

Presentations:

Technology Information:

EPA Guidance:

Federal Regulations:

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