The 11th Society of Petroleum Engineers Comparative Solution Project: Problem Definition

This article contains the description of, and call for participation in, the 11th Society of Petroleum Engineers Comparative Solution Project (the 11th SPE CSP, https://spe.org/csp). It is motivated by the simulation challenges associated with CO2 storage operations in geological settings of realistic complexity. The 11th SPE CSP contains three versions: Version 11A is a 2D geometry at the laboratory scale, inspired by a recent CO2 storage forecasting and validation study. For Version 11B, the 2D geometry and operational conditions from 11A are rescaled to field conditions characteristic of the Norwegian Continental Shelf. Finally, for Version 11C, the geometry of Version 11B is extruded to a full 3D field model. The CSP has a two-year timeline, being launched at the 2023 SPE Reservoir Simulation Conference and culminating at the 2025 SPE Reservoir Simulation Conference. A community effort is run in parallel to develop utility scripts and input files for common simulators to lower the threshold of participation; see the link to supplementary material on the CSP website. At the time of writing, complete input decks for one simulator are already ready for all three versions.