Erha and Erha North Development: Setting the Pace for Nigerian Content
Authors: Autin D.B. , Tijani A. , Boulais H. , Montbarbon S. , Underland H. 
Published: October 2008

In March 2006, ExxonMobil affiliate Esso Exploration and Production Nigeria Limited (EEPNL) started production from the world-class Erha and Erha North development, which represents EEPNL's first operated production from Nigeria's deepwater Oil Mining License (OML) 133. A key objective of the Project was to foster the development of competitive Nigerian industry capability to support future oil and gas projects and to generate long-term benefits for Nigeria. Strategies implemented to achieve this objective included utilizing local contractors and suppliers, enhancing in-country capability and capacity, transferring offshore and deepwater technology, and establishing long-term in-country relationships. Key components of the in-country execution plan included proactively maximizing Nigerian content in the Erha and Erha North Project work scopes; enhancing the capabilities of Nigerian contractors; implementing the work to realize both near-term and long-term benefits to Nigeria; and providing training, development, and employment to Nigerians.

Guided by ExxonMobil's commitment to Nigerian content, the Erha engineering, procurement, and construction (EPC) contractors exceeded contractual requirements for Nigerian content, and the Project also facilitated capacity upgrades to existing Nigerian fabrication yards that will further Nigerian participation goals for future deepwater developments. The floating production, storage, and offloading vessel (FPSO) has been operated and technically supported since start-up by a team that is made up of 85% Nigerians. In addition, the Project also achieved some significant "firsts," including the first subsea system integration test (SIT) performed in West Africa, the first fabricated production manifolds in Nigeria, and the largest catenary anchor leg mooring (CALM) buoy built in Nigeria.

This paper discusses the Project's achievements in Nigerian content, including execution successes, individual EPC contributions, and lessons learned. Also discussed are key technology transfers and new infrastructure development, both of which increase the fabrication capacity and capability available for future oil and gas developments.

Introduction

In May 1993, EEPNL and its co-venturer acquired the rights to explore offshore Oil Prospecting Lease (OPL) 209, which was converted to OML 133 in March 2006. The Nigerian National Petroleum Corporation (NNPC) is the concessionaire of the block. OML 133 is operated by EEPNL with a 56.25% working interest, and Shell Nigeria Exploration and Production Company is the only co-venturer with 43.75% working interest.

The Erha and Erha North development is located in 1,200 m of water approximately 97 km offshore Nigeria and consists of three subsea drill centers tied back to the FPSO. Drill Centers East and West (DCE and DCW) are located approximately 1.5 km from the FPSO, and Drill Center North (DCN) is an 8-km subsea tieback to DCE. The subsea production system includes trees and manifolds connected to 6-in. and 10-in. insulated steel flowlines that tie back to the FPSO via steel catenary risers (SCRs). Injection fluids are transferred from the FPSO via the SCRs and flowlines for subsea injection at the drill centers. The FPSO is a new-build, spread-moored vessel with installed capacity for 210,000 barrels per day (bpd) oil processing, 150,000 bpd water injection, and 340 million standard cubic feet per day (Mscfd) of gas injection.