Aquifer Brine - Brine production cost-benefit analysis tool documentation and draft CBA results

Abstract:

This is the report that accompanies the “Brine Production Cost Benefit Analysis” tool. This report covers the cost benefit analysis of the brine aquifer management for CO₂ storage, and analyses any benefits of producing brine to manage pressure in aquifers used to store CO₂. The CBA tool kit report provides a brief description on background details of the excel model that has been produced. It contains a user manual for the tool in Appendix 8. It provides simple cost metrics for the storage of CO₂ from CO₂Stored and demonstrated how these costs can be affected by the extraction of brine to manage the store.

Key findings:

• Value of brine production: Lifetime T&S unit costs tend to increase with brine production for a given injection scenario (although some minor savings are observed for some of the units examined); however, more importantly, more injection scenarios with higher storage capacities become feasible with brine production.
• Cost effectiveness of brine production: Brine production allows significant increase in storage capacity at similar unit costs. In addition to achieving more CO₂ storage capacity with reasonable costs, a lower unit T&S cost is achieved with brine production at Firth of Forth and Tay.
• Optimal development/configuration plans: As CAPEX of clean water discharge infrastructure on platform is negligible, sub-sea brine production does not lead to significant savings in water treatment CAPEX. However, significant savings can be achieved in injection facility CAPEX (if high costs of installing platforms can be avoided with subsea brine production – e.g. if subsea facilities connected to a hub is the most cost-effective configuration for an injection scenario).

• Value and cost of brine production: Examination of potential impact of brine production on gas fields
• Optimal development/configuration plans: Examination of further brine production scenarios that will be provided by HWU (e.g. more optimised injection/brine production scenarios if necessary) and examining different infrastructure configurations with brine production (e.g. using a central water treatment facility, which can be connected to subsea facilities or oversea platforms via brine distribution pipelines
• Informing CO₂Stored database: Reviewing learnings from the initial analysis to consider how we could model other storage units in the CO₂Stored database

Publication Year:

2016

Publisher:

ETI

DOI:

https://doi.org/10.5286/UKERC.EDC.000921

Author(s):

Durusut, E. and Tahir, F.