Study Analyzes Selection of Subsea System Architectures for Offshore CCS

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 34987, “Selection of Subsea System Architectures for Offshore CCS,” by Ana Requejo Olivan, OneSubsea; Andrew Ripley, Subsea 7; and Ian Pringle, OneSubsea, et al. The paper has not been peer reviewed. Copyright 2024 Offshore Technology Conference. _ Different subsea-control-system architecture scenarios that could be used to inject CO2 offshore from a carbon capture plant onshore were assessed. Each scenario represented a qualification step toward a minimalist, fit-for-purpose configuration, with the final system featuring simple and all-electric subsea architecture. The authors adopted a holistic approach to a hypothetical subsea carbon capture and storage (CCS) project, evaluating the effect of subsea-control-system equipment technical readiness, CCS regulatory requirements, umbilical sizing, and installation strategy. Introduction Experience indicates that one of the more-common types of offshore CCS developments comprises a coastal-based carbon capture and compression plant (generally located in a region with high industrial emitters) and an offshore reservoir selected for CO2 injection, typically a depleted hydrocarbon reservoir or an aquifer, which requires a long tieback to shore, often in excess of 100 km.