Carbon capture and storage technology has emerged as a crucial tool in helping nations transition toward lower-carbon energy while still meeting electricity demands.
CO2 emissions are captured at power plants and other facilities before being sent by pipeline or ship for long-term storage in geological formations such as oil and gas reservoirs. There are multiple geological storage solutions, but the most widely utilized storage strategy involves using used oil reservoirs as long-term repositories.
What is Carbon Capture and Storage?
Carbon Capture and Storage (CCS) is an integral technology in efforts to combat climate change, by collecting emissions from point sources like power plants and storing them underground. Furthermore, CCS can also be used to remove historical CO2 from the atmosphere through direct air capture (DACCS) or bioenergy with carbon capture storage (BECCS).
CCS technologies generally involve extracting CO2 produced by industrial processes from flue gas emissions and storing it for long-term storage in three ways: post-combustion; pre-combustion; and oxy-fuel combustion.
CO2 can either be stored permanently, or used commercially available products like concrete and plastics – an activity known as “usage”. Though usage does not directly reduce emissions or provide net climate benefits when indirect effects are considered; examples include enhanced oil recovery (EOR), which injects captured CO2 into oil reservoirs to increase extraction; as well as power generation by Core Energy/South Chester Natural Gas Processing Plant in Michigan that supplies CO2 to Chaparral’s Arkalon bioethanol plant in Texas for EOR injection.
How does CCS work?
CO2 capture is a three-step process involving the collection, transportation, and storage of carbon dioxide emissions. There are currently 15 CCS facilities operating in the US – mostly at plants processing natural gas or producing ethanol as fuel or ammonia for fertilizer manufacturing plants – that collectively capture 22 million tons annually — roughly 0.4% of annual US emissions.
CO2 captured from emission sources is transported via pipelines to geological storage sites for long-term storage, with CCS facilities typically situated close to pipelines and storage sites so as to reduce pipeline length requirements and maximize economies of scale in pipeline capacity.
CO2 can sometimes be utilized in various ways for “utilization.” One notable use involves injecting it into ageing oil wells to increase pressure inside and extract more oil, known as enhanced oil recovery (EOR). Other potential uses for the CO2 include making chemicals or fuels; however, none have yet become commercially viable due to not significantly reducing emissions or providing net climate benefits.
Why is CCS important?
CCS can play an invaluable role in decarbonizing energy-intensive industries like steel, cement, petrochemicals and power plants, which together account for over 70% of global carbon emissions from energy use. By decarbonizing these sectors using CCS it will become easier to reach zero emissions over time – ultimately saving billions on emissions costs in these industries.
Industrial processes emitting CO2 are collected, then transported via pipeline technology similar to that used for oil and natural gas transport, to an storage site for long-term storage. If necessary, CO2 could also be transported via ship depending on its source location.
Another method for carbon storage is injecting it underground, either into depleted oil and gas reservoirs or saline aquifers. This method has become the dominant approach, although ocean storage has also been explored as an option. As this form of carbon storage does not generate revenue streams, public funding must be ensured to ensure long-term compliance with regulations; nonetheless, its presence is an integral component of strategies to mitigate climate change.
What are the challenges?
Carbon capture and storage (CCS) technology has the potential to reduce greenhouse gas emissions from power plants and other industrial processes, but remains costly and in its early stages of development. Furthermore, implementation in locations far removed from geological formations suitable for CO2 storage can prove challenging.
CCS should also be seen as not replacing fossil fuels entirely; rather, it extends their use beyond what would have been possible with renewable sources alone – this can present difficulties to regions seeking to transition toward cleaner production methods while simultaneously maintaining economic growth.
CO2 captured via CCS can present an environmental risk, so monitoring and verification systems must be established to help reduce this potential hazard and guarantee its safe storage for decades to come. Yet despite these challenges, CCS remains an invaluable tool in combatting global climate change.