Ethanol Flexible Fuel Vehicle Conversions
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.
BackgroundThe 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. Regulatory RequirementsRegulations 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. Certification Process OverviewCertification 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 StandardsEmission 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 LetterA 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
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. Status of Ethanol Conversion CertificationsTo date, the following ethanol conversions have been approved by the EPA, through a Certificate of Conformity.
*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. ResourcesSome of the following documents are available as Adobe PDFs. Download Adobe Reader. Presentations:
Technology Information:
EPA Guidance:
Federal Regulations: |