A review of capacity estimates for the geological storage of carbon dioxide

Abstract

This chapter aims to assess the methodologies that have been used to develop storage capacity estimates for CO2 storage in geological formations. There are four main geological storage options, including depleted oil field, depleted gas fields, deep saline aquifers, and unmineable coal seams. These are considered by the IEA Greenhouse Gas R&D Programme to represent the most technically feasible and promising storage options. In the case of three of the storage options (depleted oil and gas fields and unmineable coal seams), the various CO2 storage capacity estimation provide a consistent picture of storage potential. However, published estimates for deep saline aquifers show an extensive range. The range is representative of the lack of knowledge of these previously unused deep saline aquifers and of the processes involved with CO2 storage. For this reason, the published storage capacity estimates for deep saline aquifers have been compared to identify the basis from which they have been derived. It also reviews the general assumptions made for the calculation of the CO2 storage capacity.