Varying the rate at which carbon dioxide is injected into underground rocks can enhance the efficiency and security of storage.
That’s according to a new study undertaken by scientists at the University of Edinburgh, which shows interrupting the injection of the greenhouse gas into geological formations increases the amount of carbon dioxide that can be trapped in tiny pores in the stone.
They believe this increases the efficiency of storage because trapped gas is less mobile and more easily contained than free-flowing gas.
However, it can increase injection pressure and would need to be managed by storage site operators.
The researchers used rock samples to simulate the injection of carbon dioxide and water – the results of these tests were then compared to the workings of a real-life storage facility, with the aim of bringing a functional carbon capture and storage (CCS) industry in the UK closer to reality.
Dr Katriona Edlmann, Chancellor’s Fellow in Energy at the University of Edinburgh, said: “Naturally, greater efficiency brings cost reductions and this will be welcome news for CCS project developers.
“We studied both in the lab and in the field to analyse what injection might look like at scale, specifically when injection rates and flow change over time. What we found was that security of storage is increased but so does pressure and this will require suitable management.”