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Abstract

At the time of project sanction in 1997, Elgin/Franklin was the largest High-Pressure High-Temperature (HP/HT) development in the world.  It required innovation across the full range of operator activities, from fluid modeling, through development concept definition, HP/HT drilling and platform design to commercial framework. 

Eight years after production first began, it is fair to say that Elgin/Franklin has not only achieved the aims of the initial project, it has clearly surpassed them.  The increased gas export capacity compared to initial design, the successful development of Glenelg (2006) and West Franklin (2007) satellites using extended reach drilling techniques and the recent drilling of an infill well in highly depleted reservoir are some of the key contributors to the success of Elgin/Franklin. 

The high level of technical innovation from project conception right through to recent drilling achievements has provided valuable experience, not only for the Total group and Elgin/Franklin partnership, but also for the industry’s HP/HT challenges.  With hindsight, using this experience, combined with a decade of further progress in technology, some of Elgin/Franklin development features could have been further optimised.  This presentation details some of the most significant feedback and provides an insight into the future of Elgin/Franklin as a mature, yet promising asset, which today is at a crossroads for further investments to ensure its continued growth.  

Introduction

The Elgin and Franklin gas condensate fields were discovered respectively in 1991 and 1986 in the Central Graben Area of the North Sea. The reservoirs (shore face sandstones of Late Jurassic age) are 5,500m deep and present abnormally high pressures (1100bar), extreme temperatures (200ºC) and significant levels of CO₂ and H₂S.  Facilities consist of two wellhead platforms, one being normally unattended (Franklin) and the other located over the Elgin field and bridge-linked to an integrated permanently manned Process-Utilities and Quarters platform (PUQ).  Glenelg and West Franklin are two HP/HT discoveries made after the initial development of Elgin/Franklin which were put in production in 2006 and 2007 respectively.

This paper presents a case history looking back at some of the key decisions taken since the Elgin/Franklin field development was submitted 12 years ago.  These decisions are analysed to see what could have been done differently, either from experience and hindsight or because of new technology available today.

From Field Development Plan to now

Field Development Plan – 1997

The Elgin/Franklin field development plan was approved in 1997.  The development was based on 12 wells (7 on Elgin, 5 on Franklin) and included the recovery of two pre-drilled appraisal wells.  Provision was included for a second Elgin wellhead platform, also bridge connectable to PUQ to be installed later if warranted.  The project included the installation of a normally unmanned wellhead platform on the Franklin field, with Franklin production transferred to Elgin PUQ via a multiphase interfield pipeline system (Figure 1).  The total estimated cost for the project was £1.6Bn, which represented a hefty investment, especially in the low hydrocarbon price environment of circa $20/bbl prevailing at the time.