National Storage CO₂ Assessment Guidance

Publication Overview

This guide provides information on where to find the material required to undertake initial national scale storage assessments. It is designed to help government bodies and policy makers with limited prior carbon capture and storage (CCS) experience find information regarding the methodology of conducting an assessment. A nationwide storage estimate is fundamental to progress CCS as a climate mitigation technology as it will determine how suitable the regional geology is for CO₂ storage and provide an initial indication of capacity.

Publication Summary

The joint UK / South Korean funded survey clearly shows that building a national CO₂ storage assessment should be compiled in a series of incremental steps:

• Develop a national strategy to produce a CO₂ storage capacity estimate. The strategy should first review whether there are existing national institutions that are capable of conducting an assessment.
• Appointment of a designated organisation, probably the national geological survey, to co-ordinate and collate key data on a country’s geology and geotechnical background.
• Set up a dedicated database that acts as a national repository for all key data that can be used to identify and characterise CO₂ storage sites.
• Categorise data sets according to the level of confidence that can be accrued to the quality of data and reliance that can be placed on it.
• Depending on the level of data categorise a national CO₂ storage resource based on an accepted terminology and scale, for example, basin-wide or regional-scale.
• Target specific formations such as DSFs that have some evidence of pressure / temperature, depth and structural characteristics that are suitable for CO₂
• Initial capacity estimates can be volumetric, bearing in mind these can only provide a general indication of capacity.
• Apply dynamic estimates based on modelled projections of capacity that take account of pressure effects and numbers of wells.
• Dynamic estimates can be further refined, depending on the quantity and quality of data available. Features such as the presence of faults, facies variations and other forms of geological heterogeneity are known to affect CO₂ storage especially migration rates and distribution and therefore capacity.