This week, Chevron presented it’s take on carbon capture and storage (CCS) through the practice of storing it permanently underground to keep it from reaching the atmosphere.
How it works
There are specific characteristics in a carbon storage site, such as whether it’s cost-effective to inject CO2, confidence in the geology to contain it, and the ability to monitor it.
- A minimum depth of 800 meters: At this depth, the CO2 compresses into a denser, “supercritical” fluid. Many times more CO2 in the same amount of space can be stored because of the increased density.
- Reservoirs and pores: Thick reservoirs with lots of granular fragments and a high capacity for flow, such as sands from ancient, buried beaches. The CO2 flows between the grains in what is known as pore space and becomes trapped there.
- Impermeable caprock: This naturally occurring barrier is a thick sequence of rocks with low or no flow capacity that covers the top of the reservoir. This “caprock” prevents the CO2 from migrating up and out of the reservoir rock and leaves it permanently trapped deep underground.
We’re really one of the few companies that have the subsurface expertise and technical capabilities to identify, screen, characterize and ultimately develop, operate and monitor a storage project
…said Mark Korte-Nahabedian, a geologist and Chevron’s lower carbon coordinator for San Joaquin Valley, California, operations.