Recent forecasts have predicted that the required number of subsea wells globally will grow to 350 to 400 per annum in the years ahead. At a presentation in Aberdeen earlier this year, BP revealed its commitment to the industry by announcing its intention to double its number of subsea wells in the next 3 to 5 years. The supermajor also revealed plans to introduce significant subsea infrastructure off Angola, Azerbaijan and Egypt.
As the global oil and gas industry focuses more and more on the subsea sector, and looks to go ever deeper in the continuing quest to recover the larger hydrocarbon fields, the subsea industry is developing its own identity and technologies.
The race to deliver effective subsea production is one that we should welcome and reflects a growing understanding within the global oil and gas industry that subsea and deepsea operations require their own technologies to make the advances we all want to see. Traditionally, we have seen operators and service companies try to answer the specific questions posed by deepsea environments by adapting shallow water technologies, and that has had varying degrees of success.
Now, rather than using shallowwater products to go deep, we see the industry develop and deploy proven and qualified deepsea products. This move will allow activity at extended depth and logically lead to the creation of effective subsea systems as the requirement for longer and longer tiebacks grows and hubs are positioned farther and farther away from each other.
In the past 5 years we have seen a massive rise in the technologies used within the deepsea arena, including advances in mooring materials, dynamic umbilicals, flowlines and, of course, the riser options. Considering the deepwater scope as a single system is the key to optimizing the solution rather than considering individual components as we conventionally approached the design. Thus we are now able to see the benefits of new technologies for deep water not just for the component alone but also for the entire deepwater system. One of the most promising of these technologies is composites and advanced materials which is among the latest developments being talked about in the industry and is set to deliver huge potential.
Work in prgress is geared to extending the knowledge and understanding of composite material behavior in deepsea applications through a number of engineering design and prototype projects.
The advantages composites offer, including weight savings, high strength and non-susceptibility to corrosion, are well documented, but it would be wrong to see them merely in terms of their benefits over steel. Where technical solutions to reduce payloads and component mass while achieving high strengths are sought for deep and ultradeepwater operations, composites become very attractive. However, perhaps the most significant advantage is as an enabling technology, either technically or commercially, allowing new approaches and designs that would not be possible or viable using traditional materials such as steel.
Carbon fiber reinforced plastic (CFRP) lines are one example. Current CFRP technology is largely centered on stressed members - rods, tendons, and stranded cables - for civil engineering applications. In the offshore oil and gas industry two company consortia (Aker Kværner/ ConocoPhillips and Freyssinet/ Soficar/IFP/Doris Engineering) have undertaken some development of this and applied it to the mooring requirements of tension-leg platforms (TLPs).
DeepSea Engineering & Management, in co-operation with Petrobras, is undertaking a development program and prototype testing of CFRP mooring lines for this purpose. Primary advantages will include reducing the vessel watch circle due to the CFRP line's far stiffer properties (thus extending the riser's operational capability), and matching the strength to diameter ratio of existing steel lines. The second advantage extends the existing fleet capability, one of the key aims being to use existing vessels equipped to handle steel lines with minimal modification, and to maximize the line length on the vessel's drum in a single deployment. In addition, high-end termination efficiency has been achieved, a key design issue for CFRP rope being how to harness all the available tensile strength.
The question is if the rapid rise in deepsea technology that we have seen in the past 12 to 18 months will continue exponentially in the years ahead or if it will level out as the understanding of deepsea's special requirements becomes more complete. The answer will depend largely on how the industry itself develops. In the last 5 years we have seen the supermajors consolidate their investment portfolios and a proliferation of smaller, independent companies emerge, acquire assets and grow. However, pressure on the availability of deepsea equipment supplies has led to premium rates being secured. So the question will be: Can the larger independents secure access to the necessary equipment to realize the growing number of opportunities that are out there? This environment obviously creates significant opportunities for the contracting industry, and those who take advantage of the new technology will reap the benefits.
The deepsea segment of the subsea industry is relatively young, and we are currently going through different designs and applications for different projects in various regions to find the most suitable approach. But as the industry matures and we learn more and more about best practice, standardization of components and systems must follow, and that will create cost savings in subsea production worldwide. The risks in using a component are reduced dramatically with each application, efficiencies increase and design changes will become minimal. In the next 5 years it is expected we will reach the point where there is a standard template for most major components in systems up to 9,843 ft (3,000 m).
The industry has addressed many challenges for deepwater systems that center on capital expenditure (capex) and risk (the product of probability and consequence of failure that ultimately has a cost). New technologies typically change and improve the capital expenditure and/or risk profile of a system or a development, thereby justifying the investment and their own deployment risk. Whilst new technology is often viewed as a product or piece of hardware, the industry has pioneered a number of engineering technology developments aimed at improved cost and/or lower risk engineering processes, two examples of which are given below.
Installation engineering optimization
Installation activities account for a high proportion of the overall capex for the subsea portion of a development and also include many of the high-risk activities. There is, therefore, direct benefit from simplified design and thorough contingency planning which has been applied by the company on projects where water depth is one primary challenge but also when the available installation equipment is limited. The company recently developed the installation process for one client's deepwater project, resulting in an extended operability window and lower installed risk by thoroughly addressing the installation engineering at an early stage in the design process to permit design modifications that provided installation advantages.
Field development optimization
The highest uncertainty with any offshore development is in the reservoir performance, and therefore designing flexibility for production, where possible, offers significant benefits. By adopting a risk-based criticality analysis to the subsea transportation system from the wellhead to the vessel, the service company was able to provide higher reliability and minimized deferred production time in the event of failure through planned remediation and repair scenario planning. This was most recently applied to one of the large West African fields currently under development.
It is clear that developing and designing the most effective system in terms of cost and efficiency is essential, and this has to be done through a thorough examination of the system configuration as a whole, not through merely focusing on the component solution to a technical problem. The use of standard components is encouraged as far as possible, but the system has to be flexible enough to incorporate thoroughly tested, fully qualified new technologies where appropriate. Pilot schemes are often a valuable and effective way of getting new technology "wet" on, for example, a non-critical well or development. By using a combination of standard components and new technologies, in conjunction with extensive criticality studies, full risk assessment, bottleneck identification and sparing studies, we achieve the optimum technical and commercial solutions and the optimum subsea system.

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