• Virtually all stations will require a dryer to be code compliant.
Station Equipment-DryerStation Equipment-Dryer
Raise gas pressure from utility service pressure to 4500 psig:
• Reciprocating compressor—usually electric motor powered.
• Redundancy through multiple compressors or portable standby compressor required if vehicles are dedicated CNG.
Station Equipment-CompressorStation Equipment-Compressor
Required for Cascade and Buffer Stations:
• ASME design Code.• 5500 psig design—4500
psig operating pressure.• Tubes or spheres.
Station Equipment-StorageStation Equipment-Storage
Dispense gas to the vehicles:
• Time fill or fast fill• Measurement (usually
only with fast fill-exception shown)
• Cardlock interface (fast fill)
Station Equipment-DispenserStation Equipment-Dispenser
Most garages will require some upgrade:
• No open flame or heaters >750F.
• Continuous exhaust and makeup air and ventilation to prevent pocketing.
• Electrical upgrades may be required—not necessarily a hazardous location.
• Gas detection system with interlocks to alarms, exhaust fans, doors…
Building ModificationsBuilding Modifications
Meet early and often with Authorities Having Jurisdiction
Partial List of Codes:• NFPA 52-Vehicular Gaseous Fuel Systems Code• NFPA 70-National Electrical Code• ASME B31.3-Process Piping• ASME Section VIII, Division 1-Unfired Pressure Vessels• NFPA 30A-Code for Motor Fuel Dispensing Facilities….• International Building Code• International Fire Code• International Mechanical Code• State and Local Codes
Good Engineering / Industry Best Practices
Permitting, Codes and ApprovalsPermitting, Codes and Approvals
Several common contracting approaches:
• Conventional Split Contract—Purchase equipment and construction under separate contracts.
• Design Build—Purchase of Design, Equipment, Permitting and Installation under a single contract.
• Throughput Contract—Design Build with payment on a per Therm charge (Lease to own)
• Maintenance can be combined or bid separately from the station construction.
• Have parts inventory before the station is commissioned —warranty is not (usually) a maintenance contract.