There is currently a trend to look seaward for locating the site of an LNG receiving terminal on all coasts of the United States. In practice, this need to consider an offshore site is virtually a mandate for public acceptance, a reasonable permitting effort, improved security and safety, ease of LNG carrier access and for economic operations.
Any offshore terminal has common challenges of: ship movements and access, mooring, LNG offloading, re-gasification, storage of either LNG or gas and eventual send-out of the gas to shore. While some offshore terminals currently in the news reflect major capital investments, alternative technologies are now available that can reduce the capital cost and shorten the project construction schedule.
The paper describes enabling technologies that make an offshore terminal technically and economically viable today for the U. S. gas markets. Alternative solutions can now be found for cryogenic transfer and storage, for mooring, for re-gasification and for storage. These technologies are compared on both a technical and economic basis. Selection criteria are presented to assist in determining which technologies are best in a given application – whether the site is in deep water or shallow. Cost information will show which alternative designs may be lower in capital cost. It is important to note that all the enabling technologies discussed herein are proven through use or have been fully vetted in model basin testing and reviewed by BV, DNV or ABS with their subsequent endorsement. All of these technologies are ready for implementation although many would first of a kind.
The natural conclusion should be that technology exists today to enable the design, fabrication, installation and operation of safe, reliable and cost effective offshore LNG receiving terminals. There are multiple means to implement an offshore terminal for the import of gas via LNG and each has it own merits for a given situation. These technologies offer "optionality" to the owner/operator.