Solutions for Fleet Managers: The Six Rs of Managing Diesel Engine Emissions

By following the “Six Rs” described below, fleet managers can help their vehicles reduce emissions.

1. Reduce Idling
   • Reduce idling by turning off engines stopped for more than a few minutes to save fuel and money while reducing air pollution and saving lives.
   • Adopt anti-idling policies for public and private fleets.
   • Pass and enforce community anti-idling legislation that will limit unnecessary idling.
2. Refuel Using Cleaner Fuels
   Switch to less polluting fuels and vehicles, including:
   • Ultra Low Sulfur Diesel (ULSD)
     o Use ULSD in non-road construction equipment
   • Clean Fuels
     o Biodiesel
     o E85
     o Compressed Natural Gas
     o Propane
   • Vehicles
     o Newer vehicles that are designed to meet new emission standards
     o Hybrids
     o Flex-fueled vehicles
     o Electric
3. Repair/Rebuild/Maintain Existing Engines
   • Routine engine maintenance provides emission reduction benefits.
   • Repair and/or rebuilding of older, non-efficient engines should result in lower emissions
4. Replace Older Fleets with Clean-Technology Equipment – Fleet Turnover
   • Replace existing fleets with newer vehicles with newer emissions technologies
   • Within fleets, prioritize vehicles for replacement based upon:
     
   • Age
   • Daily use and load amount
   • Amount of emissions
5. Repower Vehicle with Newer, Clean-Burning Engines
   • Repower existing fleets with newer engines
   • Within fleets, prioritize vehicles for engine replacement based upon age, daily use and emissions of pollution
     • Consider using:
     o Auxiliary Power Units (APUs)
     o Provide power supply overnight for comfort (heating, air conditioning, lighting, accessories)
     o Save fuel cost
     o Reduce harmful emissions
     o Roughly $6,000—$8,000 to purchase
     o Heaters
     o Accelerate and maintain window defrosting and defogging
     o Reduce emissions and eliminates idling
     o Stop white smoke
     o Extend the life of the engine
     o Substantial fuel cost savings by reducing idling time
     o Roughly $1,000 to purchase
     o Cut down on warm-up time by preheating the engine
     o Engine plug-ins
     o Reduce idling time by warming engine overnight
     o Save fuel cost
     o Reduce harmful emissions
     o One person can plug in several buses
     o Saved fuel translates into higher utility bill (weigh options)
6. Retrofit Existing Vehicles with Emissions Filters/Catalysts
   • Diesel Particulate Filters (DPFs)
   o Cost: $5,000-$9,000
   o Benefits: Reduces particulate matter by 60-90%
   o DPFs need to be cleaned every 100,000 miles
   o Lasts 7-15 years, most have a warranty of three years
   o Must be used with ULSD fuel on engines built after 1994
   • Diesel Oxidation Catalyst
   o Cost: $1,000-$2,500
   o Benefits: Reduces PM emissions by 20-30%
   o Does not require special maintenance
   o Lasts 7-15 years
   o Can be used with regular diesel fuel, but most effective with ULSD
   • Closed Crank Case Filter
   o Cost: $500-$1,000
   o Benefits: Eliminates 90%+ of in-cabin crank case emissions of fine particulate matter pollution
   o Filter needs to be changed at every oil change or after 500 hours of operation (whichever is first)
   o Lasts 5 years