Risk Assessment-Led Characterisation of the SiteChar UK North Sea Site for the Geological Storage of CO₂

Abstract

-Risk assessment-led characterisation of a site for the geological storage of CO 2 in the UK northern North Sea was performed for the EU SiteChar research project as one of a portfolio of sites. Implementation and testing of the SiteChar project site characterisation workflow has produced a 'dry-run' storage permit application that is compliant with regulatory requirements. A site suitable for commercial-scale storage was characterised, compatible with current and future industrial carbon dioxide (CO 2 ) sources in the northern UK. Pre-characterisation of the site, based on existing information acquired during hydrocarbon exploration and production, has been achieved from publicly available data. The project concept is to store captured CO 2 at a rate of 5 Mt per year for 20 years in the Blake Oil Field and surrounding Captain Sandstone saline aquifer. This commercial-scale storage of 100 Mt CO 2 can be achieved through a storage scenario combining injection of CO 2 into the oil field and concurrent water production down-dip of the field. There would be no encroachment of supercritical phase CO 2 for more than two kilometres beyond the field boundary and no adverse influence on operating hydrocarbon fields provided there is pressure management.Components of a storage permit application for the site are presented, developed as far as possible within a research project. Characterisation and technical investigations were guided by an initial assessment of perceived risks to the prospective site and a need to provide the information required for the storage permit application. The emphasis throughout was to reduce risks and uncertainty on the subsurface containment of stored CO 2 , particularly with respect to site technical performance, monitoring and regulatory issues, and effects on other resources. The results of selected risk assessment-led site characterisation investigations and the subsequent risk reassessments are described together with their implications for the understanding of the site. Additional investigations are identified that could further reduce risks and uncertainties, and enable progress toward a full storage permit application. Permit performance conditions are presented as SiteChar-recommended useful tools for discussion between the competent authority and operator.Oil DOI: 10.2516 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. & Gas Science and Technology -Rev. IFP Energies nouvelles, Vol. 70 (2015), No. 4, pp. 567-586 Ó M. Akhurst et al., published by IFP Energies nouvelles,

Multiphase Flow Characteristics of Heterogeneous Rocks From CO2 Storage Reservoirs in the United Kingdom

“…Estimates of the CO 2 storage capacity of these formations in both saline aquifers and depleted gas and oil fields in the Southern North Sea are 3.3 Gt CO 2 in the Leman formation and up to 14.6 Gt CO 2 in the Bunter formation (Holloway et al, ). Estimates of capacity in the Northern North Sea are up to 1.67 Gt CO 2 in the Captain sandstone (Akhurst et al, ; Jin et al, ; Scottish Carbon Capture and Storage, ).…”

“…These projects have now been cancelled after the removal of funding from the competition in November 2015 (Department of Energy and Climate Change, ; Shell UK Limited, ; White Rose Project, ). However, storage in the Captain sandstone saline aquifer and the depleted Goldeneye gas field are the subject of a number of modeling studies and provide an example site for many site selection methodologies (Akhurst et al, ; Delprat‐Jannaud et al, ; Scottish Carbon Capture and Storage, ; ScottishPower CCS Consortium, ). Potential CO 2 storage sites in the Central and Northern North Sea are the best understood in the UK (Brownsort et al, ) but there are no published and peer‐reviewed relative permeability or trapping curves.…”

Multiphase flow characteristics of heterogeneous rocks from CO2 storage reservoirs in the United Kingdom

“…Estimates of the CO 2 storage capacity of these formations in both saline aquifers and depleted gas and oil fields in the Southern North Sea are 3.3 Gt CO 2 in the Leman formation and up to 14.6 Gt CO 2 in the Bunter formation (Holloway et al, 2006). Estimates of capacity in the Northern North Sea are up to 1.67 Gt CO 2 in the Captain sandstone (Akhurst et al, 2011(Akhurst et al, , 2015Jin et al, 2012;Scottish Carbon Capture and Storage, 2009).…”

SiteChar – Methodology for a Fit-for-Purpose Assessment of CO2Storage Sites in Europe

“…The reader is invited to refer to Akhurst et al (2015) for further details on the risk-led assessment process for the development of the UK 'dry-run' storage permit application.…”