What Have We Learned from IEAGHG Storage Activities

Publication Overview

This report summarises key learning points on CO₂ geological storage from Operating Phase 5 of the IEA Greenhouse Gas R&D Programme (IEA GHG), which commenced in 2005 and effectively coincided with the publication of the IPCC Special Report on Carbon Dioxide Capture and Storage (IPCC SRCCS). IEA GHG activities revolve mainly around contracted studies and organisation of the international research networks. IEA GHG studies are chosen by programme members and sponsors from a wide list of proposals, ensuring those selected are focussed on topical technical issues. Study reports issued from 2005 onwards have contributed significant knowledge to major storage topics, including: regional capacity estimation; economics; environmental impact and risk assessment; well integrity and remediation of seepage; and development issues for deep saline formations.

Publication Summary

Studies have highlighted the need for further research on environmental impact assessment in the context of CO₂ geological storage. Although there is an existing knowledge base on the effects of CO₂ on ecosystems, a number of gaps in knowledge have been highlighted. Regulatory and industry attitudes to risk assessment for CO₂ geological storage were examined in a 2007 questionnaire-based study. The study found no major discrepancies between attitudes of the two groups to risk assessment, which will provide an essential framework for the regulation of storage. Network discussions have recognised performance and impact assessments as twin components of risk assessment, which forms part of a wider risk management process that incorporates monitoring and mitigation. These discussions have also highlighted the fact that current understanding of performance assessment and environmental impacts renders quantitative risk assessment as problematic.