Abstract
Subsea technology often enables the low-cost development of small marginal fields with short production lifetimes and low profit margins. However, ensuring high levels of reliability and low maintenance requirements for these subsea systems is critical for success and can be difficult to achieve. The goal of this research is to use numerical programming and optimization as a decision-support tool for the design of subsea production systems, while taking reliability and maintenance into account.
The optimization was designed to determine the most suitable subsea equipment and production strategy while considering production constraints, system downtime, lost revenue from production losses, and operational expenses. The reliability and maintenance model was integrated in the optimization model to provide the best solution possible, avoiding the problem of using two separate models that may only provide suboptimal results. This paper also discusses some of the difficulties in offshore reliability and maintenance modelling, as well as the uncertainties, constraints, and calculations used to improve the model’s accuracy.
The method was tested on a synthetic field study case in the Norwegian Continental Shelf. When reliability and maintenance parameters were included in the model, a different optimal solution was discovered. When the two solutions were compared, the new optimal design had an increase in NPV of 11 million USD over the previous one. The methodology presented advances modelling and automated decision-making in subsea production system design.
