A University research project has shown that the controlled production of brine from rocks deep beneath the North Sea can greatly increase the amount of carbon dioxide (CO2) that can be injected for storage and help to reduce the cost per tonne of tackling the UK's carbon emissions, according to new research.
Our findings suggest an eightfold increase in capacity is possible, plus a host of other benefits for a developing CCS industry in the UK.
The multi-disciplinary project, funded by the Energy Technologies Institute (ETI), has studied how brine production, more often associated with oil and gas operations, can enhance the storage potential of saline aquifers already identified as ideal CO2 stores.
The findings were presented at All-Energy 2017 and highlight other key benefits of using brine production alongside CO2 storage, including the opportunity to convert smaller aquifers into economically viable stores. It may also give certain storage sites a longer lifespan by allowing operators to increase the injection rate at a later date as new CO2 sources come on stream.
The project team was led by Heriot-Watt as a partner in Scottish Carbon Capture & Storage (SCCS), and included researchers from energy consultancy, Element Energy, along with scientists and engineers from Durham University and T2 Petroleum.
Professor Eric Mackay, of the School of Energy, Geoscience, Infrastructure and Society (EGIS), principal investigator on the project, said, “We studied a set of potential CO2 stores, identified from the UK's offshore storage atlas, to assess the value of brine production in terms of both increasing CO2 storage capacity and bringing down the unit cost of storage. Our findings suggest an eightfold increase in capacity is possible, plus a host of other benefits for a developing CCS industry in the UK.”
Emrah Durusut, of Element Energy, said, “Our study has identified a variety of strategic benefits of brine production for both policymakers and storage operators. In addition to increasing storage capacity and achieving lower minimum unit costs at certain aquifers, brine production can also increase optionality for storage operators and allow operators to better utilise their existing storage assets within a defined licence area.”