What is Geological Storage?
Geological storage, also known as geological sequestration, is the process of injecting captured carbon dioxide (CO₂) into deep underground rock formations for permanent or long-term containment. These formations typically include saline aquifers, depleted oil and gas reservoirs, and unmineable coal seams.
Why is Geological Storage important?
Geological storage is crucial for the success of carbon capture and removal technologies because it provides a reliable and potentially vast capacity for securely storing CO₂ away from the atmosphere. It is considered a key technology for achieving large-scale emissions reductions and net-zero targets, particularly for hard-to-abate industrial emissions.
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Frequently asked questions
Captured CO₂ is compressed into a supercritical fluid and injected through wells into porous rock formations located thousands of meters underground, beneath impermeable caprocks that prevent its escape.
Yes, geological storage is considered permanent or very long-term (hundreds to thousands of years, potentially millions) because the CO₂ is trapped within stable geological formations by various trapping mechanisms (e.g., structural, residual, solubility, and mineral trapping).
The main risks are CO₂ leakage back to the atmosphere, seismic activity (though rare and typically minor), and potential impacts on groundwater, all of which are managed through careful site selection, monitoring, and regulation.