Why FPSOS for The Atlantic Frontier
Authors: Kenison R.C. , Hunt C.V. 
Published: October 2008

This paper examines why ship shaped floating production storage and offloading (FPSO) systems have been selected for the first two developments on Foinaven and Schiehallion fields in West of Shetland operated by BP Exploration.

An overview of the concepts considered for the deepwater harsh environment is made against the business objectives and reservoir conditions which are the primary drivers behind development concept selection.

Discussion of technical issues for a range of concepts are held on schedule, construction, installation, safety, flexibility to production throughput, capital and operating costs.

Introduction

The intent of this paper is to discuss the rationale behind the selection of a ship shaped FPSO concept for developing the first (Foinaven) and second (Schiehallion) commercial discoveries West of Shetland (WOS). The background behind the selection was developing the best business solution, accessing latest technology where appropriate and maintaining the highest safety and environmental standards. It will also discuss the ongoing concept screening process for existing and possible future discoveries WOS.

When Foinaven was discovered in 1992 the deepest operational field in the United Kingdom was Magnus in 186 metres. Up until now all UK production had been in relatively shallow water within diver depths. The move to West of Shetlands deepwater was a major challenge to the current technology base held by industry.

Background

Before embarking on details, it is worth taking a moment to reflect on the important factors that influence field development planning and hence concept selection made by BP and Shell. These arethe Asset's declared strategic intentthe Asset's business objectivesthe geographic location of the provincethe associated environmental conditionsthe characteristics of the discovered fields

Strategic Intent.

BP and Shell's strategic intent post discovery of Foinaven in late 1992 when the potential of the basin became apparent were :To establish the basin as a major hydrocarbon producing province which will return significant and sustainable revenues to the Corporations well into the next century; and to develop a pivotal role in the province through Iicences and infrastructure.

Business Objectives.

Bring on production as quickly as possible with asserted target of late 1995/early 1996. Development would meet corporate economic targets and improve on net present value and rate of return of recent projects.

Align industry to common goals through alliancing and provide performance incentives via risk and reward. Provide the balance of development pace, scale and robustness.

Geographic Location.

The Foinaven and Schiehallion reservoirs are located in UKCS Quad 204 approximately 190 km west of the Shetland Islands in 500 metres and 375 metres water depth respectively which are significantly deeper than existing UKCS developments.

There is no hydrocarbon producing or pipeline infrastructure in the area. Two existing oil terminals to the east, Sullom Voe and Flotta on the Shetland Islands and Orkney Islands respective, receive production from the Northern and Central North Sea.