Funding to Replace Older Diesel Vehicles with Cleaner Fuel and Vehicle Options

The 2024 RDE4HT funding opportunity was opened on March 19, 2024. Please see all the related dates for this year’s funding on p.10 of the Application Guide. Note that the deadline to submit proposals to ETCleanFuels is Tuesday, April 23, 2024 at 5pm CT! If you have any questions, please reach out to Darcy Ayers at

The East Tennessee Clean Fuels Coalition’s “Reducing Diesel Emissions for a Healthier Tennessee” Rebate Program is making grant funding available in Tennessee to replace older, diesel vehicles that are class 5-8 with a) new alternative fuel vehicles (AFVs) that can run on propane, compressed natural gas (CNG), electricity, or that are hybrids, or b) new diesel vehicles.

Funding can also be requested for efforts towards replacing engines in older diesel vehicles with new alternative-fueled or diesel engines, converting OEM diesel vehicles to run on alternative fuels, and the addition of Truck Stop Electrification (TSE, and similar) equipment at Tennessee-based Travel Centers and trucking terminals.

This funding is EPA Diesel Emissions Reductions Act – or DERA – funding that is provided to states to reduce diesel emissions. The Tennessee Department of Environment and Conservation (TDEC) oversees Tennessee’s state EPA funding and is partnering with the East Tennessee Clean Fuels Coalition (ETCleanFuels) to manage the Rebate Program and funding and direct it into efforts that reduce diesel emissions in Tennessee from Memphis to Mountain City.

Get the Application Documents

First, grab the full RFP and Application Guide here. (32 pp) All of the below applications and appendices are included in this document.

Individual pieces can be found here:

Use the below materials and templates for Title VI compliance as needed:

Funded Fleets

across Tennessee

Any entity that owns and operates vehicles in Tennessee for a Tennessee-based fleet or fleet domicile site may apply. This includes contractors that provide transportation or hauling services.

  • Bledsoe County Schools

  • Clarksville-Montgomery County Schools (x3)

  • Clean Sweep, Inc. (x2)

  • FedEx Express

  • Hancock County Schools (x2)

  • Hawkins County Schools

  • Knoxville Utilities Board

  • Memphis Fire Department (x2)

  • Rhea County Schools

  • Roane County Schools

  • Rye Engineering

  • Ursa Major Logistics

  • Weakley County Schools (x2)

  • Washington County Schools (x2)

  • Waste Management (x4)

rde4ht 2024 tn trucking newsletter ad (1)


at a glance

The funding period for the 2023-24 application period is open as of March 19th. The deadline to apply is April 23rd.

Anyone with a fleet that resides in Tennessee can apply for a maximum of 15 new vehicles or engine replacements. Priority will be on new alternative fuel school buses and other trucks over new diesel buses or trucks.

Public and private locations that would like to install TSE (Truck Stop Electrification), electric TRUs or “reefers” (trailer refrigeration units, or eTRU when able to run off of Shorepower-type electricity) may also apply.

  • Recipient must put a 3-inch hole in the engine block of the vehicle.
  • Recipient must cut both frame rails of the vehicle in half.

Photographic evidence of vehicle disaposal must be submitted as a requirement of funding. This includes at least three photos of the engine hole (from receding distances) and two photos of the frame rails, before and after for each rail.

If needed, you can request approval to crush or destroy an vehicle – engine included. You must request this in advance of disposal and receive approval from ETCleanFuels before proceeding, and video evidence will be required that shows the vehicle’s VIN before destruction.

  • The existing vehicle(s) must be fully operational.
  • The participating fleet owner must have owned and operated the vehicle(s) during the 2 years prior to replacement or upgrade.
  • The existing vehicle(s) must have at least 3 years remaining life at the time of replacement or upgrade.
  • The existing on-road vehicle(s) must have traveled at least 7,000 miles/year during the 2 years prior to replacement or upgrade. (school buses may use mileage from the calendar year [Jan-Dec] 2019)
  • The existing nonroad vehicle(s) must have been operated at least 500 hours/year during the two years prior to replacement or upgrade.

The total amount of funding available for all applicants in the 2023-2024 funding period is $404,000.

Primarily in Tennessee, RDE4HT funding is used by fleets to replace class 5-8 diesel vehicles or engines. Funding comes as a rebate on a certain percentage of your replacement cost that is paid out once all contract requirements have been met. The maximum vehicle funding is based on how well the new vehicle or engine meets or beats the current EPA NOx emissions standard. Successful applicants can receive funding up to:

  • 25% of the total new vehicle cost that meet the current NOx standard of 0.2 grams per brake horsepower-hour (g/bhp-hr),
  • 35% of the total new vehicle cost for vehicles that reach what’s called “low-NOx” emissions of 0.1 g/bhp-hr, and
  • 45% of the total new vehicles cost for vehicles that have no tailpipe.

However, there are some other funding options, including a) repowering an old diesel vehicle, b) converting old diesel vehicles to run on alternative fuels, c) installing truck stop electrification (TSE) equipment at travel stops or private trucking terminals, and d) installing electric transport refrigeration units (eTRU) equipment on trailers.

This program is funded by the EPA’s Diesel Emission Reduction Act (DERA), and is distributed through the Tennessee Department of Environment and Conservation and East Tennessee Clean Fuels (ETCleanFuels). The funds for RDE4HT come from the state of Tennessee’s allotment for state EPA funding.

Eligibility for Applicants

Vehicles / Engines

Any entity that owns and operates vehicles in Tennessee for a Tennessee-based fleet or fleet domicile site may apply; this includes contractors that provide transportation or hauling services. The entity itself or the contractor may apply, but whoever owns the vehicles should be the applicant. Vehicles that are leased are not allowable in this program. Public or private entities in Tennessee may apply for funding.

  • Any one entity may apply for a maximum of 15 new vehicles or engine replacements.

  • The new vehicle(s) that are purchased must be kept in service for a minimum of three (3) years and be used on similar routes with a similar number of miles per year as the older vehicles that are being replaced.

  • The applicant must provide with their proposal to ETCleanFuels one quote for each new vehicle or engine for which funding is being requested. For engines, the quote should include costs for equipment and labor.

  • The old vehicles must be able to start and move in all directions.

  • New vehicles must meet federal safety standards and required warranties.

  • Usage requirement. Old vehicles must have a) accumulated at least 10,000 or more miles per vehicle OR b) been in use for at least three days per week over the most recent 12 months, operating in regular service.

  • The engine(s) from the old vehicles must be destroyed. The rest of the parts, body, or frame may be sold for recycling or kept as replacement parts as needed. Proof of engine destruction must be provided to ETCleanFuels. This can include, as examples, a) drilling a hole in the block and submitting photos clearly showing the hole in the block, or b) crushing the old vehicles and engines and submitting documentation from the crusher. Photos or documentation must be provided for each older diesel vehicle engine being destroyed.

  • Vehicle/Engine Age. Please see the table on p. 4 in the RFP for specifics about which old vehicle years are allowable for replacement.

  • Vehicle replacements. Funding can cover 25% – 45% of the total new vehicle costs depending on emissions reductions and the type of fuel being used in the new vehicle. Please see the breakdown on p. 4 in the RFP for more information.

  • Engine replacements. Funding can cover 40% – 60% of the cost (equipment and labor) of replacing a diesel engine; please see the breakdown on p. 4 in the RFP for clarification.

  • Alternative fuel conversions. A maximum of 40% of the cost (equipment and labor) of an eligible certified or compliant clean alternative fuel conversion.


Public Travel Centers and private trucking “terminals” that are located in Tennessee and that would like to install TSE, electric TRUs or “reefers” (trailer refrigeration units, or eTRU when able to run off of Shorepower-type electricity) map apply. This can include (but is not limited to) equipment utilized at public travel centers and private trucking fleet terminals.

  • No more than 30% of the total cost to purchase and install equipment that is used to provide heating, cooling and/or electric power to the tractor cab or trailer shall be covered.

  • For eTRU units, no more than 25% of the total cost of a new eTRU system or entire trailer with an attached eTRU system shall be covered.

  • There is no limit on the number of spaces or trucks/trailers that may be applied for.

  • The funding can go towards a) the electrification infrastructure that will allow the diesel-using equipment on the tractor or trailer to turn off and use electricity instead, and b) a trailer or the equipment that would be installed on a trailer to operate a cooling system on electricity in lieu of diesel. This includes necessary installation costs. Please note that applications that request funding for the eTRU that goes on the trailer (and potentially the new trailer too) must be approved by EPA.

  • The funding cannot pay for APUs for tractors.

QUESTIONS? Please contact Darcy Ayers of East Tennessee Clean Fuels at 865‐974‐6451 or