Vehicle and Engine Alternative Fuel Conversions
- How to submit information to EPA to demonstrate compliance
- Lists of EPA-compliant conversion systems
Overview of Conversions
- Green Vehicle Guide's: Alternative vehicle fuels
Conversion systems modify vehicles and engines so that they can run on different fuels than the ones for which they were originally designed.
- Clean Air Act prohibition: 42 U.S.C. §7522(a) — Refer to sub-section (3)
- Emission controls in the converted vehicle or engine will continue to function properly; and
- Pollution will not increase as a result of conversion.
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Related Guidance Letters
- Updated Assigned Deterioration Factors for Alternative Fuel Converters (PDF) (5 pp, 56K, CD-12-07(Revised), March 30, 2012)
- Updated Certification Guidance for Fuel Converters (PDF)(13 pp, 308 K, October 2010)
Includes guidance on whether conversions to full battery electric require alterative fuel vehicle certification.
- Updated Certification Guidance for Fuel Converters (PDF)(22 pp, 150K, CISD-06-02[LD-AFC], February 3, 2006)
Provides information for small volume manufacturers who convert vehicles and engines to operate on alternative fuels.
How to Submit Information to EPA to Demonstrate Compliance
EPA's Final Rule for Clean Alternative Fuel Vehicle and Engine Conversions spells out processes through which conversion manufacturers may demonstrate compliance with vehicle and engine emissions requirements. The processes differ depending on the age of the vehicle or engine to be converted.
- Conversion systems to be used on new and relatively new vehicles/engines;
- Conversion systems to be used on intermediate-age vehicles/engines; and
- Conversion systems to be used on outside useful life vehicles/engines.
The following information summarizes the requirements. Regulated parties should always refer to the regulations for compliance purposes.
Conversion Systems to be used on New and Relatively New Vehicles
- Certification and fuel economy for passenger vehicles (light-duty)
- Certification for commercial trucks and buses (heavy-duty)