Waste Idle Time

By far, waste idle time is the largest contributor wasted gas to avoidable pollution and wasted gas. Contrary to popular belief, restarting a car does not burn more fuel than leaving it idling. In fact, idling for just 10 seconds wastes more gas than restarting the engine. Frequent restarts are no longer hard on today’s car’s engine and battery, and the vehicle’s catalytic converter warms up much faster when the car is being driven.

  • Idling a car wastes up to 0.5 gallons of fuel per hour
  • Idling a medium-duty truck wastes 0.4 to 0.6 gallons of fuel per hour
  • Engine idling increases vehicle maintenance costs
  • Engine idling can shorten vehicle life

Common waste idling occurrences:

  • Running engine while parked for breaks, paperwork, or phone calls
  • During the course of pickup and deliveries
  • Using drive-through windows
  • Leaving engine on in convenience store-parking lots
  • At railroad crossings
  • Using remote starters

Restart wear is much less costly than the cost of wasted fuel. Reducing vehicle idling will save money with decreased engine wear and gas burned as well as help lower CO2 pollution.

Converted to Dollars

With a fleet of 10 medium-duty trucks: If each truck has ten 10-minute idling episodes per workday, using ~0.5 gal/hr, and fuel costs $3.50/gallon, the annual cost of idled fuel for the fleet is ~$7,550.

Source: USDE IdleBox Toolkit  https://cleancities.energy.gov/technical-assistance/idlebox/

Driver Behavior


For every 5 mph traveled over 65 mph, vehicle efficiency is reduced by 7%. This is because as speed increases, so does the aerodynamic drag, which forces the engine to work harder and consume more fuel.

Aggressive Driving

Rapid acceleration and harsh braking reduce fuel economy by as much as 33% at highway speeds and 5% in city, according to the EPA. Drivers who make habitually heavy accelerate, weave through traffic, or slam on the brakes are increasing fuel consumption, as well as wear on engine and breaks.

CO2 Emissions

We realize the impact vehicles have on the environment with greenhouse gases and other air pollutants. W4 products to support corporate and government environmental initiatives and mandates. Working closely with fleet managers, we create customized solutions that monitor and help reduce environmental impact.

About 19.64 pounds of CO2 are produced from burning a gallon of gasoline that does not contain ethanol (E10). About 22.38 pounds of CO2 are produced from burning a gallon of diesel fuel.

EIA estimates that U.S. motor gasoline and diesel (distillate) fuel consumption for transportation in 2015 resulted in the emission of about 1,105 million metric tons of CO2 and 440 million metric tons of CO2, respectively, for a total of 1,545 million metric tons of CO2. This total was equivalent to 83% of total U.S. transportation sector CO2 emissions in 2015.