Intelligent oilfields: managing the interfaces

The oilfield service industry lately has developed advanced intelligent completion systems that manage and monitor well production and/or injection. These technologies allow the operator to change flow characteristics without the need for well intervention. Additionally, data parameters acquired from advanced in-well sensors lead to a better understanding of specific production and/or injection zones, and near-well and inter-well reservoir characteristics. Intelligent wells are allowing operators to significantly increase a well's expected net present value by:

• Enhancing profitability by reducing workover/intervention cost and eliminating deferred production
• Accelerating cash flow through pressure management of multiple zones
• Increasing reservoir knowledge and management capabilities to allow for incremental recoverables of hydrocarbons from a producing asset.

Understanding the mechanics

It is anticipated that from 2002, every deepwater well will employ permanent data acquisition and remote control at some time in its life. It is interesting to note, however, that while the benefits of intelligent well technologies are easily appreciated, the mechanics by which these systems are commissioned are poorly understood.

As with any system deployment, critical planning and execution are paramount to realizing the anticipated value. A candid assessment of risk needs to be established prior to any application. It is through this review that the areas of reliability, probability of failure, and criticality of that failure are weighed.

While managing the interfaces from the tubing hanger through the wellhead to the surface system is straightforward, what is less apparent is the equally critical need to understand and engineer the system beyond both ends of this picture.

In the downhole arena, the oil and gas industry continues to tailor well completions to anticipated production or injection. This leads to many designer well completions that are engineered right up to the last minute. It is this flexibility that allows critical efficiencies to be realized in the overall sweep of the surrounding wellbore.

To ensure that intelligent well systems realize their full potential, they must be given the same consideration to integration that any completion plan currently demands. Thus, beyond flow control and sensor deployment, equal consideration must be given to the enabling ancillary completion equipment. Terminations, feedthroughs, bypasses, and splices must be engineered to work seamlessly with higher-level completion components.

The challenges of moving instrumentation and control below the production packer are daunting. From a mechanical standpoint, the space available in a wellbore has always been limited. This is especially true where sand control is a challenge. From a performance standpoint, a well can be hot, caustic, high-pressure, and in the case of deepwater and long-reach horizontal wells, a very long way from the drilling rig or production terminal.

Integrating data

Beyond mechanical and reliability issues lie those associated with collection, organization, and manipulation. The latter transform raw data into valuable information. Permanent sensors will provide the raw data for automation and well optimization. However, key reservoir models will have to be updated "on-the-fly" to realize the full benefit of intelligent well systems. Accomplishing these real-time updates will depend on delivering the right data to the right individuals at the right time. The challenge at this end of the spectrum will be to integrate a tremendous amount of data and control into communication systems and surface databases that are sometimes antiquated and almost always limited in cross-functional access.

Thus, integrating data may present a greater challenge to the successful application of intelligent well technologies than engineering and deploying the hardware. Multidisciplinary, inter-company cooperation, coordination, and system integration will be required to overcome these challenges.

Realizing the benefits

The industry is in the early stages of intelligent field technology, in a situation analogous to that surrounding the development of 3D seismic. There were questions about value versus cost. There were questions about how all of the data could be stored and manipulated to yield a useful result. There were complaints about the increased level of technology required.

Ultimately, however, 3D seismic proved to be one of the most important technological breakthroughs in an industry where profitability is closely tied to innovation and technology. Today 3D seismic is applied to solve problems, reduce uncertainties, and increase asset value across the entire range of exploration, development, and production operations.

Intelligent well technology holds the promise for similar breakthrough improvements in real-time reservoir characterization and production management that will lead to increased asset value. While we are at least 3-10 years away from realizing the field-management benefits of this technology, it is important to remember the lessons of previous "revolutions" in oilfield history.

Many technological innovations have been spawned in an environment of low commodity prices. Those that have had a lasting, positive impact have been nurtured by perseverance, ongoing open dialogue among operators and service companies, and a willingness to "push the envelope."

Jack Angel
Baker Oil Tools
Houston, Texas