Wag Injector Wells: How Intelligent Completion Technology Could Impact on Project Economics

Nowadays WAG (water alternate gas) injector is considered a new frontier for subsea field with injectors or disposal wells in order to minimize CAPEX and obtain same benefits on field substain. Looking forwards to forthcoming subsea development, to implement this technology has been considered a must in order to reduce the number of wells dedicated to injection and reduce subsea facilities layed for injection both gas and water. Company is going to develop field in Angola and Nigeria, where oil has different characteristics but with the same constrains related to reservoir pressure maintenance. This abstract shall consider a study performed by headquarter related to the possible scenario accepting WAG injection using intelligent completion technology and the relative risk analysis. This technology for the company is considered a key choice in order to complete, partialize and control flowing in different layers, with different pressures and different characteristics. Conscious of this ability engineering center decided to move in this direction (more or less one years ago in 2010) and started a dedicated detailed study to consider Angolan field. The field have a water depth and environment with 1,500 – 2,000 m of water depth. The goal of the project will be achieved a cut off 50% of the CAPEX related to injectors in both fields, at the same time considering also interface with subsea facilities and surface facilitites. Abstract aims to show what is the impact in terms of economic, evaluated on this project, beginning by base case of injectors dedicated for each level, to final project approved and actually in execution. Terms of comparison will be the delta CAPEX, NPV and IRR of both projects.