More Pictures...

The concept
The SRV is a modified standard LNG vessel. The main additions to a standard LNG vessel will be:

• A cylindrical trunk forward of tank no 1. to accommodate the submerged turret mooring buoy and swivel system
• Skid-mounted regasification units on deck
• Bow- and stern thrusters
• Supplementary electrical power supply
• Supplementary steam production for regasification

The SRV can be a conversion or a newbuilding, and will also be capable of traditional delivery of LNG. Conversion studies of our own vessels have been performed and no showstoppers have been identified.

LNG is pumped from the tanks and sent to regasification units mounted on the vessel’s deck. Pressure is boosted by large cryogenic LNG pumps. Steam generated by auxillary boilers in the vessel main engine room produces the heat necessary to regasify the LNG in the regasification unit’s heat exchanger. The regasification units design has been developed by Hamworthy Gas Systems Norway.

Regasified LNG is discharged via a turret and swivel through a mooring and unloading buoy connected to a riser and subsea pipeline, designed by Advanced Production Loading (APL) and based on their North Sea proven STL technology. Two separate buoys will ensure continuous send-out by overlap between arriving and departing SRVs.

The containment system can be either reinforced membrane type, Moss spherical tank type or SPB type. The important issue is to ensure that the containment system is designed to allow for maximum operational flexibility with regards to filling levels to ensure that sloshing does not occur during operation in exposed offshore locations with partially filled cargo tanks.

The benefits
By discharging the LNG through a SRV the need for a land based receiving and regasification terminal will be redundant. This has many obvious benefits, some of which are:

• No land or port requirements for the receiving terminal
• No physical encroachment to the local land based environment
• No visual impact from shore
• Shorter overall time to market
• Enhanced safety
• Higher delivery regularity, even in harsh weather conditions

Normally one additional SRV is required to deliver the same volume as a traditional solution due to the regasifiaction time of each vessel on the buoy. In spite of this, the economics of the SRV system compares very favourably to traditional LNG receiving terminals for small- to medium re-gasification volumes and short- to medium shipping distances (up to 4000 nmiles). The SRV system may be used in harsh- (and benign) environment world-wide.