Diesel Fact Sheets

Click on the headings below to view a fact sheet with detailed information on each of the following diesel fuel topics:

Selective Catalytic Reduction

  • What is Selective Catalytic Reduction (SCR)?
  • Why SCR?
  • How does the SCR system work?
  • Why reduce NOx?
  • What is Diesel Exhaust Fluid (DEF)?
  • Are freezing temperatures a problem with DEF?
  • Are there any dangers handling DEF?
  • What prevents diesel fuels or other non-DEF substances from being pumped into the DEF tank?
  • How much DEF is needed?
  • What happens if a vehicle runs out of DEF?
  • What are the advantages for a fleet using SCR technology?
  • Are there any disadvantages to using SCR technology?

Biodiesel Fact Sheet

  • What is Biodiesel Fuel?
  • How is Biodiesel Made?
  • Benefits
  • Disadvantages
  • Average Biodiesel Emissions Compared to Petroleum Diesel

Diesel Retrofit Technology

  • Bolt-On" Retrofit Technology
    • Diesel Particulate Filters (DPFs)
    • Partial Diesel Particulate Filters
    • Diesel Oxidation Catalysts (DOCs)
    • Closed Crankcase Vent Filtration (CCVF) System 
  • Fuel-Based Retrofit Technology
    • Biodiesel
    • Fuel-Borne Catalyst

Idling Technology Fact Sheet

Maryland's Idling Law

  • Diesel Exhaust Health Effects
  • The Costs of Engine Idling
  • Energy and Economic Impacts
  • Average Truck Idle/Rest Period, Emissions and Fuel Use
  • Idle Reduction Technology
    • Electronic Idle Limiters
      • Idle Shutdown System
      • Automatic Stop-Start System
    • Auxiliary Devices
      • Fuel-Fired Heaters
      • Auxiliary Power Units
      • Battery Air Conditioning Systems
      • Thermal Storage Systems
  • Truck Stop Electrification (TSE)
    • Advanced TSE
    • Shorepower
    • Electric Truck Refrigeration Units

Smartway Transport Program

SmartWay Transport Partners

  • Using the SmartWay Partner Logo
  • SmartWay Technology Options, Costs, Fuel Savings, Net Monthly Savings
  • Financing Options
  • State Implementation Plan (SIP) Guidelines
    • Truck Idling
    • Diesel Retrofits
    • SmartWay Upgrade Kits

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