Fleets that choose natural gas have a range of options to consider for vehicle refueling. If an existing public refueling station is to be used, fill time and site access are important considerations. A private onsite refueling station may be suitable if the fleet’s total natural gas fuel volume is sufficient. A simple rule of thumb is that typically 20 medium or heavy vehicles are needed in order to consider a private onsite station. Another option may involve accessing a nearby private station owned by another fleet.
Natural gas refueling stations can be designed to match the fill times provided by diesel or gasoline stations. One additional option with compressed natural gas (CNG) is to fill all fleet vehicles overnight in an eight to twelve hour window using a time fill station.
Before determining station needs, fleets must decide whether CNG or liquefied natural gas (LNG) is to be used. Each form of natural gas requires a different set of equipment to dispense fuel. A CNG station can be installed wherever there is a natural gas pipe in the ground. An LNG station is similar to a diesel station where fuel must be delivered by tanker truck and stored onsite.
The basic equipment needed for each type of station is as follows:
- A CNG refueling station needs a compressor, gas dryer, storage tanks, and other equipment to dispense fuel at the right pressure into a vehicle.
- An LNG station requires a cryogenic pump to move fuel from a large storage vessel to a dispenser and into a vehicle.
A refueling station that offers both CNG and LNG is also possible. This type of station – an LCNG station – has both LNG and CNG dispensers. LCNG stations are usually based on LNG being available at the station. The CNG is produced by warming the LNG and bringing it to the right pressure for CNG dispensing.