Clarifying Quantitative Language in the SRMS

Abstract

Abstract Numbers tend to have one meaning, whereas words can be open to interpretation, so one might expect the language of probability to be better at communicating the uncertainty in CO2 geological storage resource estimates to project stakeholders. However, rather than assigning a probability value to deterministic estimates, current reporting systems use quantitative expressions which may not fully convey the appropriate degree of confidence that the deterministically estimated CO2 volumes will be stored. Using published work on cognitive bias by acknowledged energy sector consultants, drawing on research by statisticians and carrying out their own tests, the authors reveal that there are different perceptions of the language of quantitative probability from those suggested in the SPE's storage resource management system (SRMS). Tests show that energy industry professionals believe the probability value that corresponds to reasonable certainty is somewhat lower than the implied 90% figure assigned to the probabilistic low estimate of recoverable volumes, generally taken as equivalent to the proven deterministic case. The divergence between deterministic language and associated and perceived probability grows when considering other storage capacity classes. Such perceptions may lead to optimistic expectations and result in sub-optimal development decisions. The assignment of probability values to deterministic storage resource classes is avoided traditionally, so perhaps the adoption of clearer and more appropriate quantitative language should be considered by altering the SRMS" text to better describe the likelihood of the outcome of an event.