Assessing Offshore Prospects for CO2 Storage in Portugal: From Pilot-Scale to Commercial Site

Within frame of the PilotSTRATEGY project, comprehensive geological characterization studies were conducted in the Lusitanian Basin to assess the CO2 storage potential in this Portuguese region. In the offshore area of this sedimentary basin, three promising geological structures were identified. Relying on well and geophysical data, each of them has been characterized to define their structural closure scenarios, reservoir petrophysical properties and dimensions as potential CO2 storage sites.

The current work presents a volumetric stochastic approach used to assess and integrate reservoir geological uncertainties for determining the CO2 storage capacities of the three identified structures. Following the volumetric estimation, a preliminary long-term storage capacity assessment was conducted for the most promising prospect Q4-TV1. The goal was to consider supplementary physical trapping mechanisms, such as mineral and solubility trapping, and to evaluate their impacts on storage capacity and CO2 plume dispersion over time.

By combining both storage capacity assessments, this work provides valuable insights and confirms the outstanding potential of prospect Q4-TV1 as a CO2 pilot injection site. Furthermore, this study highlights the feasibility of upscaling this prospect to a commercial-scale, contributing to the development of a viable carbon sink in the Lusitanian Basin.