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Verified Technologies for SmartWay and Clean Diesel

Learn About Idling Reduction for Locomotives

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Benefits and Methods for Reducing Idling

Operator comfort is essential to maintaining focus and high performance in locomotive shipping.  However, changing how you achieve it by reducing idling can help you achieve significant benefits.

Benefits from reducing long-duration idling include:
  • Decreasing fuel costs,
  • Decreasing engine maintenance costs;
  • Extending engine life;
  • Improving operator well-being by decreasing noise levels;
  • Decreasing emissions that are harmful to the environment; and
  • Improving relationships with surrounding communities.
There are two ways of reducing idling:
  1. Behavioral strategies that are promoted by EPA; and
  2. Idling Reduction Technologies, which are assessed and verified by EPA.

Behavioral Strategies for Reducing Idling

Create policies and programs that limit idling of locomotives between work events.  These programs include training employees to commit to using techniques to eliminate unnecessary idling and usually place time limits on the time a locomotive is allowed to idle when running the main engine is not needed.

Idling Reduction Technologies (IRTs)

IRTs allow locomotive engine operators to reduce long-duration idling of the main propulsion engine by using an alternative technology.

An IRT device generally has the following three characteristics:
  1. Is installed on a vehicle (e.g., bus, truck, locomotive, automobile, marine vessel, equipment, etc.) or at a location;
  2. Reduces unnecessary main engine idling of the vehicle or equipment; and/or
  3. Provides services (e.g., heat, air conditioning, and/or electricity) to the vehicle or equipment that would otherwise require the operation of the main drive engine while the vehicle or equipment is temporarily parked or remains stationary.

There are four types of verified IRTs for locomotives:

  1. Automatic engine shut down/start up (AESS)
    An automatic engine shut down/start up system controls the engine by stopping or starting it without operator action.  An automatic engine shut-down/start-up system not only turns off the main engine while idling but can re-start the engine when necessary. Re-start of the main engine is typically based on a set time period, engine or ambient temperature, and other parameters (e.g., battery charge). To date, SmartWay has only verified AESS systems for locomotives.
  2. Fuel Operated Heaters aka Direct Fired Heaters (FOH aka DFH)
    Designed to heat the coolant and oil to allow main engine shutdown in cold temperatures, the system does not use a generator to produce auxiliary power. Instead, it circulates and heats the engine coolant and oil to a target temperature of 120 F. FOHs can also provide heat to warm in cab and passenger areas. 
  3. Auxiliary Power Units/Generator Sets (APUs/GS)
    These are diesel-powered engines (20 to 50 horsepower) that are installed on the locomotive to provide air conditioning, heat, and electrical power to run accessories like lights, on-board equipment, and appliances.
  4. Shore Connection Systems (SCS)
    An SCS system allows locomotives to “plug into” an electrical power source instead of using its diesel engines while at the rail yard.

Quantifying Emission Reductions for State Implementation Plans 

Reducing long-duration locomotive idling will reduce emissions of nitrogen oxides (NOx), carbon monoxide (CO), and particulate matter (PM). For state and local air quality planners and transportation officials, these emission reductions can be used in air quality plans such as state implementation plans, as well as transportation and general conformity. 

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