Scaling Cleaner Freight Movement

Various Options Exist to Control Idling

Idle reduction is about cost savings and driver comfort. Historically, a large amount of operating time of a sleeper tractor-trailer engine was idling. This could be 45% or more, where the driver is sleeping, eating, working or relaxing in his or her vehicle when they are not driving.

Each year in the United States sleeper tractors burn millions of gallons of diesel fuel while idling. The average truck idles about 1,000 hours a year. This is costly, noisy, dirty and not efficient. A plethora of idle-reduction solutions have emerged including on-board diesel and battery units, engine start/stop, diesel heaters and driver training and incentives to drastically lower idling. Each, along with other complementary actions, have their benefits and challenges with respect to fuel and emissions reductions, upfront cost, maintenance costs, infrastructure, etc.

Idle Reduction Technologies

Fleet Survey Results

Decision-Making Tools

Our team produced top-line tools to assist fleets in making their idle-reduction technology choice. The Confidence Matrix summarizes the study findings and indicates NACFE’s confidence in the various idle-reduction technology solutions. In addition, the report contains challenges and changes charts for each of the anchor technologies. The charts can be found in section 9 of the report.


As a result of research and interviews the study team reached the following conclusions concerning idle reduction in the sleeper cab market:

  1. Reducing idle is good for the environment, saves fuel and improves a fleet’s “green” image.
  2. A 10% reduction in annualized idle percentage is worth about 1% in fuel economy that results in a $500 to $700 annual savings assuming 100,000 miles a year and diesel at $3 a gallon.
  3. Driver hiring, comfort and retention are mentioned in almost every conversation about idle-reduction technologies. Some have said that offering a good solution is a requirement for hiring and retaining drivers.
  4. There is no “one size fits all” solution to idle reduction.
  5. Drivers are still a very important part (If not the most important part) of successful management of idle times.
  6. Depending on “shore power” (outside electrical connection) to be available is not a reasonable idle-reduction solution for most fleets as the number of electrified parking spaces is extremely small compared to the number of trucks that need to be parked at any given time.
  7. Most suppliers of idle-reduction technologies mention that their solution helps minimize maintenance costs, particularly in the vehicle’s aftertreatment system. However, we have been unable to uncover any data that actually substantiates those claims.
  8. The answer to the question of the resale value of trucks equipped with idle-reduction technology is unclear.
  9. Maintenance of the vehicle’s battery connections and electrical systems is critical to getting the best performance out of idle-reduction technologies.
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