Prospects and Challenges for the FPSO

Abstract

ABSTRACT The reasons for the recent growth of interest in the use of the Floating Production Storage and Off-loading (FPSO) system in oilfield developments are examined. An evaluation of oil field characteristics that influencencept selection is made which shows that the FPSO is a very flexible solution in a wide range of situations. Costs and cost drivers are discussed and some measures of cost effectiveness are proposed to serve as benchmarks for the future. Some technologydevelopment challenges are identified. The findings give a high level view of the techno-economic prospects for the FPSO in field developments over the next decade. INTRODUCTION Floating Production became a reality in 1977 with the installation of the Argyll Semi-submersible based system and the Castellon Floating Production Storage and Off-loading (FPSO) system. Since that time, the Semi-submersible and FPSO systems have progressed at roughly similar rates until the present time when thereare 21 Semi-submersible and 27 FPSO floating production systems in operation today. In 1984 the first Tension Leg Platform (TLP) was installed at Hutton and today there are 4 of this type of floating production system. Construction has started of a further 6 Semi-submersibles, 11 FPSOs cand 3 TLPs, see Figure 1. In the difficult business environment of the mid 1990's, with the prospect of oil prices remaining low well into the next century and the challenge of exploiting oil reserves in deeper waters, interest in floating production is flourishing. Eight years ago a review of Shell's undeveloped offshore reserves showed that they were concentrated in the established producing basins, 75% were in less than 150 m water depth, 80%were within 50 km of existing processing facilities and export systems and only 307. were oil. on this basis it wasconcluded that there was only limited scope for the application of floating production. Of new offshore prospects evaluated in 1994, 65% were oil of which 40% were in water depths greater than 300 meters and many were in new frontiers areas such as West Africa. This change in the character of prospects to deeper water and frontier areas has significantly increased the potential for Floating Production Systems. More surprisingly, in the shallower waters of established regions such as the North Sea, Floating ProductionSystems are proving attractive in fields with small reserves, even when these are relatively close to existing infra-structure. Of the various floating production concepts suitable for oil field development, greatest interest seems to be focused on the FPSO with its ability to combineproduction, storage and off-loading capability into one facility that can be deployed in water depths from 30 meters to more than 1,000 meters in practically all environmental conditions. This interest manifests itself in oil companies increasingly including the FPSO as a natural option in field development planning and the contracting industry making the construction or ownership and leasing of FPSOS part of their future business plans. The objective of this paper is to examine why there is a growing interest in the FPSO concept.