NATURAL GAS FUELS: CNG & LNG
Natural gas as a transportation fuel
Turn the earth's great resource into your company's best resource with Agility Fuel Solutions. Fuel represents as much as 25% of a typical fleet's operating costs. By fueling with natural gas, fleet owners can reduce fuel costs by more than 50%. Natural gas has been used in the transportation industry for over 15 years and has proven to be easy to use, safe and reliable.
There are two primary types of commonly available natural gas fuel, compressed (CNG) and liquefied (LNG). Both are viable fuel sources for heavy duty vehicles. Depending on the end-users' requirements, either form may be the most suitable.
Agility Fuel Solutions is the primary fuel system supplier to most of the leading domestic OEMs and natural gas fleets. We are experienced with both CNG and LNG fuel systems, and provide a complete end-to-end product offering from the analysis and design phase through after-market service and warranty support for both fuel types.
CNG
  • Physical Form: Gas stored at high pressure at 3,600 psi
  • Volume vs Diesel: 4x
  • Cost: Lower cost to produce and store
  • Refueling: Easy
  • System Pressure: 60 - 4,500 psi
  • Hold Time: Unlimited (no fuel loss)
  • Storage: Carbon fiber wrapped cylinders
  • Conclusions: New, lightweight large capacity CNG tanks enable long-haul trucking applications.
Agility FS Truck
Freightliner with behind the cab installation shown above.
CNG Conversion Formulas
Pounds of CNG Fuel Lbs. of CNG @ 3,600 PSI = Water Volume (cu. in.) multiplied by 0.0079
Lbs. of CNG @ 3,000 PSI = Water Volume (cu. in.) multiplied by 0.0069
Standard Cubic Feet (SCF) SCF @ 70°F and 3,600 PSI = Water Volume (cu. in.) divided by 5.861
SCF @ 70°F and 3,000 PSI = Water Volume (cu. in.) divided by 6.657
Diesel/Gasoline Gallon Equivalents Gasoline Gallon Equivalent (GGE) = SCF of Natural Gas divided by 123
Diesel Gallon Equivalent (DGE) = SCF of Natural Gas divided by 139
LNG
  • Physical Form: Liquid produced cryogenically at -260F
  • Volume vs Diesel: 2x
  • Cost: Higher cost to process, liquefy and store
  • Refueling: Requires special handling equipment
  • System Pressure: 60 - 230 psi
  • Hold Time: Limited (fuel will vent if not used)
  • Storage: Vacuum-insulated stainless steel tanks
  • Conclusions: LNG's high energy density makes it relevant to trucking and off-road applications where space is at a premium.
Truck with LNG Side Mount
LNG Pressure - Temperature - Density
Pressure (PSI)Temperature (F)Density (Lbs/Gal.)
0 -259 3.54
50 -230 3.29
100 -200 3.11
150 -186 2.97
200 -175 2.85
250 -167 2.76
300 -158 2.68
350 -150 2.60