CNG Storage

GreenLine designs and builds both Buffer Storage and Cascade Storage systems for use with our CNG Fueling Systems. All of our Storage Systems feature our AutoFill VPF SystemWith AutoFill VPF the CNG Fueling Systems and Storage Systems have been integrated using programmable logic and sensors in the Fueling System with control valving in the storage system to fully automate and control the Buffer Storage and NGV refueling process, completely eliminating the need to manually manipulate valves or control the compressor. and comply with NFPA 52 requirements for automatic shutoff in the event of an emergency stop is activation. Both Buffer and Cascade storage provide a reservoir of compressed gas to improve fueling system performance, however, the two differ in their sophistication and cost.

Buffer Storage


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GreenLine’s Buffer Storage systems  are custom build to meet your fast-fill needs. These systems go beyond the traditional dumb CNG storage and incorporate features that automate the management of NGV refueling with our AutoFill VPF system. Our Buffer Storage Systems utilize DOT/FMVSS certified storage cylinders are skid mounted making them easy to relocate. Buffer Storage systems are available in capacities ranging from 11 to 102 GGE.

Tube Storage


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Cascade Storage is the cornerstone of fast-fill CNG fueling systems. The compressed gas stored on the cascade makes it possible to fill many NGV tanks in rapid succession. A Cascade Storage system typically consists of three banks (storage vessels) of CNG stored at 4,200 psi or higher using ASME certified storage. Cascade Storage implements a priority system that dispenses CNG from the lowest pressure bank first and then switches to successively higher pressure banks, if necessary, to complete the NGV refueling. Because the storage is at higher pressure and in multiple banks NGV refueling from Cascade Storage is extremely efficient resulting in approximately a 40 percent yield (percent of the cascade that is available for NGV fueling).

Sphere Storage


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Sphere Specifications

  • 48" inside diameter
  • 33.5 cubic ft. water volume                            
  • 250 gallon capacity
  • 1" relief valve with isolation and bleed block included 
  • 1/2" drain valve included
  • Outer dimensions (63"(H) x 56"(W)
  • Weight 8,735 lbs.
  • White epoxy paint