Project integrated LNG offloading availability assessment for FLNG

Abstract

This extended abstract explains a combined heuristic, analytical, and probabilistic process to evaluate LNG offshore offloading availability in combination with facility uptime and commercial drivers such as LNG sales/supply contracts. The heuristic assessment is informed by facility operators’, LNGC masters’, and tug operators’ experiences in offshore offloading and berthing operations. The analytical process includes assessment of met-ocean, mooring, manoeuvrability simulation, model testing and event forecasting methods. Gaps about uncertainties for future predictions are filled by probabilistic Monte-Carlo simulations. The heuristic, analytical, and probabilistic approach, combined with commercial drivers, is put together into uptime assessment to forecast the techno-commercial performance of the facility. The uptime assessment enables: confidence on achievable LNG throughput, the best for facility configuration and size, the best for facility location and facility’s operational expenditures; contractual viability—for LNG supplier and gas off-taker; and, key to terminal performance guarantee to gas off-takers. This process has been developed within INTECSEA during the past six years and has been applied to more than 15 LNG offshore offloading facilities at varying geographical locations. This extended abstract explores the key drivers and describes the effect on those key drivers due to varying location, varying technology, or LNG sales/supply contracting strategy. The key drivers include: achievable LNG throughput, uptime, downtime, demurrage, cargo cancellation, facility downturn, and partial LNG offloading. The process described is specific to side-by-side offloading operations; however, it can also be adapted to standard jetty offloading operations and tandem offloading operations.