Abstract
The Arctic regions offer significant resource bases for energy supplies for the future. The Arctic developments has been challenged during the last years due to relatively high risk and cost levels related to the remote locations, harsh environment and environmental risks. The price of energy has fallen significantly and Liquefied Natural Gas (LNG) prices has followed the oil market, therefor the development of LNG facilities in the Arctic has to offer substancial cost benefits over what was planned some few years back.
Gas fields in the Arctic can be developed with LNG plants onshore, Floating LNG (FLNG) or by Gravity Based Structure (GBS) LNG solutions. Onshore developments has been the only alternative developed to date but logistical, foundation and lower productivity for construction, hook up and commissioning in arctic conditions has enabled another development concept to be evaluated. FLNG in shallow water and ice infested areas has not yet been considered a feasible development solution.
The GBS LNG concept offers solutions to many of the challenges in developing a large scale LNG plant in the arctic. The self contained GBS LNG based on compact design with integrated topside, Product storage and offloading in one unit can improve the execution of:
Construction and integration in a yard instead of in an remote localization with harsh environment large parts of the year
Reduced logistical challenges and no ice breaking tansport vessels required
Locating the GBS LNG in permafrost free site
Concrete GBS can be constructed locally to ensure substantial local content
Securing the project schedule by working in a controlled environment with established infrastructure and work force
Significant reduction in bulk quantities due to compact design
Integrated ice barrier and potentially ice management systems in the GBS
The GBS LNG concept has been developed to be a flexible solution where;
Train size and number of trains can be accommodated - up to 10 MTPA LNG capacity per GBS
Large flexibility in LNG and condensate storage capacity
Water depth ranging from 13-30m
Design one build many - easy hook up for multiple LNG GBSs
Cooling medium (Air or Water cooled)
Driver selection - GT or Electrical drive
Self contained with Living Quarter, Flare and utilities in produced on board
Flare can be installed on GB S
This paper is based on several conceptual and pre-FEED studies for the arctic and sub arctic environment where the GBS LNG solution has been evaluated favourable over the onshore development alternative, especially in location with ice infested waters and were permafrost on land is present.
