First all-electric intelligent completion system evolves for deep water: when the world's first all-electric intelligent completion was installed in a subsea deepwater well, it was the culmination of five years of development, testing and trials. System acceptance has been restrained, but improvements have been made

World Oil, May, 2005 by Oswaldo M. Moreira

On Aug. 3, 2003, the world's first subsea, deepwater, all-electric intelligent completion system was installed in the 8-MLS-67HA-RJS well, in 3,540 ft (1,180 m) of water at Marlim Sul field. The site is about 60 mi (100 km) offshore Campos (Campos basin), Brazil. It is tied back to the Petrobras 40 FPSO--the world's largest-capacity floating production unit--via a 3.7-mi (6-km) umbilical. The installation culminated a five-year, joint development project by Petrobras and Baker Oil Tools in association with other firms.

The all-electric intelligent completion project was launched in 1999 as part of Petrobras' Program of Technological Innovation and Deep and Ultra-Deepwater Advanced Development (PROCAP 3000) strategic initiative. PROCAP 3000 has sought to enable Petrobras to operate in water depths exceeding 10,000 ft (3,300 m). System development was methodical, testing was stringent, and subsea installation was trouble-free. Yet, five years after initiation and more than one year after first installation, acceptance of this system appears to have grown little.

Why? The answers offer lessons for both operators and service companies regarding commercialization of new technologies.

Background. Over 75% of Brazilian oil and gas reserves are beneath deep and ultra-deep water. This statistic has driven Petrobras to become a pioneer in deepwater and subsea technologies. It also drove Petrobras to be among the first E&P companies to recognize the value of, and thus pursue, intelligent well technologies to manage future deepwater, subsea field developments.

In 2000, Petrobras launched the PROCAP 3000 initiative. Anticipating some of its systemic projects, the company began looking at intelligent well systems that met their internal criteria, and were either commercially available or under development. In addition to meeting strict safety criteria, the objectives were to: 1) Address historical, operational reliability concerns related to hydraulically operated downhole flow control devices; 2) Expand on the value of additional downhole sensors to resolve uncertainties critical to deepwater production and reservoir management; and 3) Reduce/eliminate direct rig intervention requirements.

In December 1999, Petrobras sponsored an intelligent completions workshop in Brazil. It was an opportunity for service companies competing in the intelligent completions arena to present state-of-the-art technologies designed to help Petrobras address PROCAP 3000 challenges. Based on its workshop presentation, Baker Oil Tools was awarded a technical cooperation agreement for an all-electric, intelligent well system to be installed in a deepwater subsea well.

Baker's InCharge system was already about 70% developed at the time of this agreement. It controls and monitors flow through electrically powered, infinitely variable chokes known as intelligent production regulators (IPRs) and downhole, single-phase, flow measurement units (FMUs). The system combines extensively tested/proven electronic components from the space industry with conventional electrical and mechanical components. The latter items came from logging and completion tools for terminations, bypasses, choking absorption, temperature insulation, feedthroughs and splices. The system achieves downhole monitoring and control with reliability levels comparable to proven completion designs and techniques.

Power and communication (data acquisition and commands) are run through a single, 1/4-in. twisted pair tubing-encased conductor (TEC) line that penetrates packers and wellhead. The surface control system (SCS) can control and monitor up to 12 zones (or nodes) in a single well, and up to 12 wells. The system's power-on-communications architecture requires little or no retrofit of existing subsea infrastructure (wellhead, trees and installation/workover equipment). This is because a spare electrical penetration is likely to be available in most cases. System requirements are within the scope of subsea connectors and other components' technical and functional specifications.

Most of the joint efforts between Petrobras and Baker Oil Tools were focused on ultra-deepwater deployment considerations. The firms jointly developed a testing plan that consisted of a laboratory well deployment test, a site integration test with the subsea tree and field evaluation tests.

SYSTEM DESIGN REQUIREMENTS

Due to the project's nature, which was to qualify this technology for high-end applications, system selection and completion design were defined prior to final well assignment. At first glance, this may seem at cross-purposes. But when viewed in contrast to existing completion requirements in Campos basin fields, it was not difficult to find a candidate well that matched the aforementioned requirements and would benefit from the results.

The high cost associated with exploring and developing deep and ultra-deepwater fields is the strongest driver for motivating the standardization process culture that is in place in most deepwater applications, either subsea or downhole. Through standardization, operators seek to: