Pioneering energy development companies and the supporting industries are overcoming many of the technical and cost challenges that have historically plagued developers of oil and gas discoveries in remote and ultra-deepwater locations. However, the lack of viable gas offtake solutions has left stranded not only abundant non-associated natural gas resources in these regions, but has also restricted access to highly valuable oil resources because of the inability to properly dispose or commercialize the associated gas. Advancements in compressed natural gas (CNG) technologies will help to unlock these vital resources.

EnerSea's VOTRANSTM (Volume Optimized Transport and Storage) technology contains unique features that will enable the loading, storage and transport of lean or rich associated natural gas directly from the supply source, with a minimum amount of offshore production processing, and the subsequent offloading of gas at the market. Previous attempts to develop CNG marine transport technologies have not been able to provide an elegant solution for mitigating the dynamic effects involved with the high rate transfer of rich gas volumes and their entrained gas liquids.

CNG transport projects can make use of proven deepwater buoy-type terminals and cargo transfer systems to facilitate cost effective and reliable direct gas loading from remote and deep water production facilities. Advantages of the system also include the ability to provide a highly cost effective offshore gas offloading operation into near shore subsea pipeline infrastructure for the safe and secure delivery of gas to the market. This latter feature should prove to be a highly attractive solution to governments and local communities that are concerned with the prospect of siting large gas receiving terminals, such as LNG regasification and storage facilities, onshore and near sensitive areas.

This paper will describe the innovative VOTRANS gas handling and storage technologies that have been designed by EnerSea to accommodate rich associated gas transport. It will also present an overview of a typical associated gas development project in a deepwater application utilizing such a CNG marine transport solution, as well as the option for floating gas storage facilities at the field.


As oil fields continue to be developed more remotely from shore and into ever deeper waters, the challenges for E&P companies continue to increase. Technologies for transporting oil from these deepwater developments are well-known and proven, however solutions for associated gas disposal are more difficult to come by and have slowed down, if not shelved, some valuable oil and gas developments worldwide.

The natural gas maritime transport industry has prospered recently, building momentum upon the successful track record of LNG. However, due to the very high costs and low efficiency of floating liquefaction designs, offshore LNG solutions have not developed as rapidly as some experts have expected over the past several years. The CNG marine transport industry may be able to provide solutions for these challenging associated gas developments.

This paper introduces the CNG marine transport technology that has been developed by EnerSea Transport LLC and how it can be applied to deepwater associated gas projects.

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