Projecting Shuttle Tanker Fleet for Gulf of Mexico FPSOs: Discrete Event Simulation

Abstract

Abstract This paper will present a Discrete Event Simulation (DES) based solution for an optimum shuttle tanker fleet to serve the present and future FPSO based Gulf of Mexico (GoM) production. The simulation takes into account average ‘field lifecycle’ based production rates of specific developments and the sensitivity of ‘offloading availability’ to variables such as shuttle tanker size, loading rate, distance to market etc. A probabilistic representation of downtime associated with wave, wind, currents, maintenance etc. at the FPSOs and random weather and non-weather delays at the receiving terminals have also been considered in this effort. Despite the impressive pipeline infrastructure available in the GoM, none of it currently reaches some of the newer fields being discovered in over 5000ft water depths in the lower tertiary trends. The high cost of pipeline extensions in ultra-deep water (UDW) and uncertainty in the producibility of reservoirs has multiple operators considering an FPSO - Shuttle Tanker (ST) based solution for production export. This paper would help operators considering this option to understand the limitations and potential options in using shuttle tankers in serving the field(s). The assessment of offloading availability for shuttle tankers to serve multiple fields would be made on the basis of production rate, loading rate and tanker size using a Discrete Event Simulation (DES) model subject to threshold and offloading operational downtime. The development of the Cascade-Chinook field at the US GoM has established its viability using dedicated shuttle tankers. However, potential of synergy in using a common fleet of shuttle tankers exists subject to further FPSO based developments in the near future. This paper explores the technical and logistical feasibility of such a possibility.