Optimizing Carbon Capture and Storage in Multiple Reservoirs: Advanced Completion Design with Flow Control Valves

Summary This paper investigates completion design options for Carbon Capture and Storage (CCS) wells, particularly focusing on multiple reservoir zones. It explores an advanced strategy, such as the use of Flow Control Valves (FCVs), which challenges the industry's conventional preference for simplicity. This study evaluates the potential benefits and project-level impact of implementing complex completion designs in CO2 storage wells—specifically those targeting multiple reservoir zones. The design focuses on enhancing CO2 storage capacity, reducing the Area of Review (AoR), improving reservoir efficiency, and managing operational risks. A core aspect of the study is the assessment of surface-controlled selective multizone completions using advanced technologies such as Flow Control Valves (FCVs) in well architecture. The analysis highlights how, under specific subsurface conditions, these advanced completions can unlock superior performance and support more sustainable and flexible injection strategies. The study addresses key focus areas critical to the success of CCS well completions, including the technical challenges associated with complex designs, strategies to manage fill-up across stacked reservoir zones, and the project-level implications of deploying advanced completion systems. It further explores the development of risk mitigation frameworks tailored to intricate subsurface architectures, alongside efforts to optimize the overall completion design and planning workflow. In scenarios involving two or more viable CO2 storage intervals, one of the primary challenges is ensuring effective flow distribution across zones while minimizing the Area of Review (AoR) extension. To this end, the study highlights four fundamental design drivers: assessing the feasibility of simultaneous injection into multiple zones through a single well, ensuring robust zonal isolation within the completion, preventing crossflow between intervals, and enabling surface-controlled injection balancing to optimize both injection rates and pressure management. Ultimately, this work advocates for a paradigm shift in CCS completion practices—demonstrating that, when properly engineered, complex completions may offer superior outcomes, promoting more efficient and sustainable carbon storage.