Operation of North Sea FPSOs: 1995-2000 and Beyond
Authors: Mapes Graham , Casias Christopher 
Published: October 2008

Based on documented trends and experience, projections are made for the future operation of North Sea FPSOs. Changes include improved interactions with shuttle tankers and standby vessels and increased environmental regulation. Recommendations are also made for improving the design and operability of FPSOs while increasing profitability for both contractors and operators.

Introduction

Over the past fifteen years, Bluewater Engineering has gained considerable experience in designing, building, and operating Floating, Production, Storage and Offloading installations (FPSOs). For the past seven years, the company has concentrated on the North Sea. Taking into account the obstacles the company faced over this period of time, this paper attempts to put into perspective Bluewater's point of view of the upcoming operational challenges in the year 2000 and beyond. Rather than focusing on technological and design aspects of an FPSO, this paper uses performance indicators (criteria, objectives, limits and standards) as a basis for analyzing a number of elements related to the operational performance of an FPSO.

First, the changing responsibilities of shuttle tankers and standby vessels are considered. For these vessels, whose performance criteria have changed significantly, and will continue to change, a comparison is made of what the performance capabilities were five years ago, what they are now, and what they are expected to be five years from now. In many cases, the future expectations of performance capabilities are based on projections made from both ongoing industry improvements and Bluewater's own objectives.

Environmental discharge limits, particularly strategems for decreasing the levels of hydrocarbons to air and water, are also presented. Typical emissions indicators (produced water, flaring, fugitive emissions) from Bluewater's fleet of FPSOs are presented and the company's perspective on how emissions to environmental media can be reduced, are discussed.

Finally, the structure of contracts associated with design, construction, and operational phases is discussed. For the first two phases, the performance objectives are normally based on time and cost. An overall review of industry performance indicates a rise in cost overruns and schedule delays on the delivery of new-built FPSOs. Are the objectives unrealistic, or are there means for improvement through the restructuring of contracts? Contract structure can also impact an FPSO owner's/operator's ability to meet performance objectives in the operational phase. Performance objectives such as those defined for shuttle tankers and standby vessels need to be properly considered within the contract structure to ensure that there are mechanisms for implementing requirements and standards.

It is the opinion of the authors that these elements represent ongoing challenges to the industry as a whole and need to be considered in order to improve the operational performance of an FPSO.

A Fresh Appraisal of Factors that Influence Operations

An FPSO is a complex facility that is highly dependent on the successful integration of marine and production systems. This implies that the design must be optimised on the basis of its intended operating environment, because it is the final design which ultimately has the most significant impact on operations and, subsequently, up-time.