Project Challenge
Pacific Northwest LNG’s proposed export terminal in northwest British Columbia required a coordinated basis for production, storage and marine capacity. Variations in gas feed and LNG production affected tank inventories, while vessel arrivals and ocean conditions introduced uncertainty into the timing of exports.
Storage requirements therefore depended on more than nominal plant output. Delays between ship calls could allow inventories to accumulate, creating exposure to full storage tanks and production interruptions. The study examined these interactions to inform terminal master planning, assess operating resilience and evaluate requirements for future throughput expansion.
Modelling Approach
The discrete-event simulation connected onshore LNG production with offshore marine operations. Its scope followed the export chain from pipeline feed and liquefaction through storage, berth operations and vessel departures.
The model represented variability in production rates, LNG tank levels and available storage capacity. Marine operations included vessel calls, berth occupancy, queues, service times and departure timing. Weather distributions and transit through Triple Island were incorporated to examine how ocean conditions and vessel movements affected the export system.
Linking these activities allowed production and inventory changes to be evaluated alongside shipping events. Weather and vessel timing influenced how long LNG remained in storage between ship calls, making it possible to investigate the relationship between marine delays, storage saturation and potential production shut-ins.
Decisions Supported
The analysis evaluated the number of LNG storage tanks required and the maximum throughput achievable with the proposed terminal design. It also examined berth occupancy, vessel queueing and service times to assess marine capacity and delays.
Alternative ship-arrival patterns and ocean conditions were tested to understand their implications for tank inventories and production continuity. These scenarios supported comparison of storage and marine-capacity alternatives, including the risk that delayed exports could fill available tankage.
The integrated model also supported assessment of future expansion requirements. Production, storage and shipping could be considered together when evaluating whether proposed changes addressed the constraints affecting overall terminal throughput.
Outcomes and Applications
The model provided a quantitative basis for comparing tankage, marine capacity and expansion alternatives. It connected shipping variability with the risk of storage saturation and interruptions to LNG production, supporting decisions during export-terminal master planning.
The central finding was that LNG storage cannot be sized independently of shipping. Variable vessel arrivals and ocean conditions can increase inventory requirements and expose production to interruption even when nominal plant and berth capacities appear sufficient. Evaluating the complete export chain helped reveal these interactions and supported assessment of capacity and operating resilience.
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