Transitional Low-Emission Vehicle

A Transitional Low-Emission Vehicle (TLEV) refers to a vehicle that meets specific emissions standards set by either the Environmental Protection Agency (EPA) or the California Air Resources Board (CARB). TLEVs are designed to produce fewer emissions compared to vehicles meeting federal Tier 1 standards, but they are not as clean as vehicles meeting Low-Emission Vehicle (LEV) standards. Here are some key points about TLEVs:

1. Emissions Standards: TLEVs adhere to emissions standards set by either the EPA’s Clean-Fuel Vehicle (CFV) TLEV program or CARB’s TLEV program. These standards require vehicles to emit lower levels of pollutants such as hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx) compared to vehicles meeting federal Tier 1 standards.
2. Federal and State Regulations: TLEVs are eligible for certain federal and state programs aimed at reducing vehicle emissions and promoting cleaner transportation technologies. For example, they may be eligible for the federal California Pilot Program, which encourages the use of alternative fuel vehicles, but they may not qualify for programs such as the Clean-Fuel Fleet Program, which typically require vehicles to meet stricter emissions standards.
3. Transitional Nature: The designation “transitional” indicates that TLEVs represent an intermediate stage between older, less efficient vehicles and newer, more environmentally friendly vehicles. They are designed to help bridge the gap between existing emissions standards and future, more stringent requirements.
4. Less Stringent Standards: While TLEVs produce fewer emissions than federal Tier 1 vehicles, they are not as clean as vehicles meeting LEV standards. The TLEV standards are generally less stringent than LEV standards, allowing manufacturers more flexibility in meeting emissions targets.

Transitional Low-Emission Vehicles play a role in reducing vehicle emissions and improving air quality, particularly in areas with significant pollution concerns. However, they are considered an intermediate step toward the adoption of cleaner vehicle technologies and more stringent emissions standards in the future.