New approaches to CNG technology include fiber-reinforced plastic containers and containers in the form of metal tubes of moderate diameter (typically 6" or 168 mm internal diameter). In one approach (Coselle) of tubing is wound on a spindle. Such spindles are stackable and may be connected to achieve the desired capacity. In another approach (GASVESSEL) composite material containers are adopted allowing to increase the commercial payload for the CNG ship and significantly reduce the transport cost.
