CCS

CCS stands for carbon capture and storage, a set of technologies designed to reduce CO2 emissions by capturing it from emission sources or removing it from the atmosphere, transporting the captured gas, and injecting it into geological formations for long-term storage. When CO2 is captured and used commercially, the broader term CCUS (carbon capture, utilization, and storage) is sometimes used.

Capture methods include post-combustion capture, which removes CO2 from flue gases; pre-combustion capture, which separates CO2 before combustion in gasification or reforming processes; and oxy-fuel combustion, which produces a concentrated CO2 stream. Direct air capture is related but typically treated as a separate technology.

Transport involves compressing CO2 and moving it through pipelines or shipping to storage sites. Storage typically occurs in geological formations such as depleted oil and gas reservoirs or deep saline aquifers, where CO2 is trapped and monitored over long time scales to prevent leakage. Monitoring and risk assessment are essential components.

Applications and status vary by region. CCS is viewed as a key option for decarbonizing hard-to-electrify sectors like cement and steel, and for reducing emissions from fossil fuel–fired power plants. As of the 2020s, several large-scale CCS projects operate or are under construction, supported by policy incentives and climate scenarios that require negative emissions.

Critics point to high costs, energy penalties, and long-term liability, while supporters emphasize potential to deliver large-scale emissions reductions, job creation, and security of energy supply when paired with other decarbonization measures.