Using the Choquet integral for screening geological CO 2 storage sites

For geological CO2 storage site selection, it is desirable to reduce the number of candidate sites through a screening process before detailed site characterization is performed. Screening generally involves defi ning a number of criteria which then need to be evaluated for each site. The importance of each criterion to the fi nal evaluation will generally be different. Weights refl ecting the relative importance of these criteria can be provided by experts. To evaluate a site, each criterion must be evaluated and scored, and then aggregated, taking into account the importance of the criteria. We propose the use of the Choquet integral for aggregating the scores. The Choquet integral considers the interactions among criteria, i.e. whether they are independent, complementary to each other, or partially repetitive. We also evaluate the Shapley index, which demonstrates how the importance of a given piece of information may change if it is considered by itself or together with other available information. An illustrative example demonstrates how the Choquet integral properly accounts for the presence of redundancy in two site‐evaluation criteria, making the screening process more defensible than the standard weighted‐average approach. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd