Enhancing Forecast Reliability Through Adoption of Integrated Production Modelling Technology

Abstract

Abstract Reliable reservoir and well performance predictions are essential to successful production, investment planning and capital stewardship for large liquefied natural gas (LNG) projects located offshore Western Australia. Successfully achieving this enables maximisation of revenues without eroding project net present value. In order to make informed decisions about the timing of future gas supply for LNG plants, the values and trade-offs of different timings for future wells need to be assessed. To achieve this, excellent reservoir characterisation is desirable, as well as reliable modelling of the field management rules, production system and well constraints. This paper will discuss the improved modelling aspect of the field management rules, production system and well constraints that will be used as a basis for future investment timing decisions for the Wheatstone project. Steps to improve the gas supply forecast included incorporating known production network constraints and downtime associated with well failure, in an effort to more accurately reflect production capability and operating envelopes. The adoption of a new software technology has supported the implementation of detailed and accurate field management logic into coupled production system – reservoir simulation models through a rule-based model controller. This enabled a more accurate representation of operational limitations, as well as more stable and reproducible simulation runs, modifiable well rate allocation schemes and well routing between production corridors. Improving the simulation models with those functionalities required close integration with flow assurance and subsea engineers, as well as operations, which resulted in a better cross-functional understanding of how certain constraints can affect ultimate field recovery and future field development decisions. Enhancing the representation of the production profiles has also resulted in higher confidence in making more informed decisions for future drilling campaigns timing, scope and well locations. Future model improvements will consist of incorporating revised operational constraints and updating the model's Field Management Controller as the production networks constraints and limitation are better characterised once the Project is in production phase. Evergreen updates of the reservoir models and the field management model are expected to be performed as new surveillance and production data become available, which will support an improved decision process for future gas supply investment.