Green Vehicle Laws and Regulations in Tennessee
Tennessee has a handful of green vehicle laws specific to protecting the environment. These include vehicle emissions testing for most alternative fuel vehicles (excluding electric cars), liquefied gas and compressed natural gas taxes, and licensing and driving restrictions for low-speed electric vehicles and medium-speed vehicles.
As TN increases its focus on environmental issues, these regulations and related green driver incentives might also change. In addition to referencing this page, also consult your local Department of Motor Vehicles (DOR) branch and the Alternative Fuels Data Center.
Tennessee Vehicle Emissions Testing
All county emission testing ended on February 2022.
Liquefied Gas Tax
If you drive a TN-registered motor vehicle powered by liquefied gas on Tennessee's pubic highways, you must pay a:
- $.14 per-gallon use tax.
- Pre-paid annual vehicle tax (based on the classification* of your car, determined by maximum gross weight).
The per-gallon use tax requirement includes vehicles equipped to use liquefied gas interchangeably with another motor fuel, but excludes governmental agencies. Also, out-of-state drivers must still pay the per-gallon tax, however this is accounted for at the pump.
*Classifications defined by declared maximum gross weight (including vehicle and load) and the corresponding annual fees are as follows:
- Passenger car—$70.
- Class 1 (non-passenger; 9,000 pounds or fewer)—$84.
- Class 2 (16,000 pounds or fewer)—$84.
- Class 3 (20,000 or fewer)—$100.
- Class 4 (26,000 or fewer)—$100.
- Class 5 (more than 26,000)—$114.
Get the specifics under Tennessee Code 67-3-1101 through 67-3-1103, and 67-3-1106 or refer to the TN Department of Revenue's Motor Fuel Taxes page.
Liquefied Gas Defined
Tennessee defines liquid gas as all combustible gases that remain in a gaseous state at 60 degrees Fahrenheit and at a pressure of 14.7 pounds per square inch (psi). This definition excludes gasoline, diesel fuel, and compressed natural gas (CNG).
Compressed Natural Gas Tax and User Permits
Tennessee imposes a use tax on compressed natural gas* at the rate of $.13 per gallon for consumers buying CNG to power a motor vehicle on TN's public highways. Government agencies are exempt.
Additionally, Tennessee requires users of compressed natural gas for use in a vehicle to obtain a CNG user's permit and file returns when buying from a CNG dealer not selling through a metered dispenser. For example, to buy CNG in bottles, you need a user's permit, and you must file a natural gas user's tax return. If you buy CNG from a dealer using metered dispensers, you can skip the permit.
Download a Compressed Natural Gas Tax Return from the Tennessee Department of Revenue, and consult the TN DOR's Motor Fuel Taxes page for more info.
*For the purpose of determining the tax on compressed natural gas, TN uses a gallon equivalent factor of 5.66 pounds per gallon.
Low Speed Electric Vehicle Driving Restrictions
Low- and Medium-Speed Vehicles Defined
Tennessee defines low-speed electric vehicles and medium-speed vehicles in a slightly different way. Both require operators to hold a valid Class D driver's license.
Low-speed vehicles are electric vehicles that:
- Have four wheels.
- Can reach a maximum speed of 20 miles per hour (mph), but not exceed 25 mph.
- Comply with the safety standards detailed in Title 49 of the U.S. Code of Federal Regulations, section 571.500.
This definition excludes golf carts, but includes neighborhood vehicles.
Medium-speed vehicles are electric or gas-powered vehicles that:
- Have four wheels.
- Can reach a maximum speed of 30 miles per hour (mph), but not exceed 35 mph.
- Comply with the safety standards detailed in Title 49 of the U.S. Code of Federal Regulations, section 571.500.
This definition also excludes golf carts.
Road Restrictions for Low- and Medium-Speed Vehicles
Tennessee prohibits the use of low-speed electric vehicles and medium-speed vehicles* on any TN streets that have a posted speed limit more than 35 mph and 40 mph, respectively. The exception to the rule is when crossing a road or street with a speed limit more than the maximums previously mentioned.
*Even while traveling on a road with a speed limit of 40 or fewer mph, medium-speed vehicles are still prohibited to exceed 35 mph.
Tennessee's counties or municipalities may prohibit low- and medium-speed vehicles from any roads under their jurisdiction in the interest of public safety. For full details on operating prohibitions, consult Tennessee Code 55-8-191.
Find a Nearby Tennessee Emissions Testing Station
Locate the closest TN smog and emissions testing station with the widget below: