Carbon capture and storage (CCS) is one of five technologies that can help us reach net zero emissions. CCS reduces emissions from power plants and other industrial facilities while decarbonising sectors that have historically been difficult to tackle.
CO2 captured from the atmosphere is stored permanently underground using geological formations such as saline formations, depleted oil and gas reservoirs or unmineable coal areas.
What is CCS?
Carbon capture and storage (CCS) involves collecting CO2 emissions from fossil fuel power plants or other sources and safely storing it underground; CCS is one of many tools needed to meet global climate targets such as those set forth by Paris Agreement in limiting temperature increases to 1.5 degC above pre-industrial levels.
CCS works by injecting carbon dioxide deep underground, often into rock formations like saline aquifers or depleted oil and gas fields. For instance, one project in the UK, Zero Carbon Humber plans to store CO2 emissions at Endurance about 0.62 miles (1km).
CCS technology can also be applied to bioenergy with carbon capture and storage (BCS), in which CO2 is stored at a biomass plant before being burned to produce electricity or fuels, but this comes with substantial environmental risks due to land usage requirements for crops or trees and associated forest clearance and ecosystem destruction. Furthermore, BCS adds greenhouse gas emissions from its use of fossil fuels within its operations, making this form of CCS even less environmentally-friendly than before.
How does CCS work?
Carbon capture and storage (CCS) technology enables plants to reduce carbon emissions. This is an essential technology, since burning fossil fuels such as coal, oil, or natural gas releases CO2, contributing significantly to global warming. If we want to stay below 2 degrees Celsius rise in global temperature it’s crucial that we dramatically cut back CO2 production from these sources.
CO2 produced from power plants and industrial processes is captured, transported to a CCS site, where it’s stored safely underground rock formations such as saline aquifers and depleted gas fields for storage. Transport may occur via pipeline or ships.
CO2 can be stored for an indefinite amount of time or used to produce more fuel or for other purposes like enriching concrete leading to stronger buildings. Furthermore, geological formations known as enhanced rock weathering (ERW) provide the ideal place for CO2 to remain safe over millions of years.
What are the benefits of CCS?
CCS is an essential technology that can aid global warming by reducing emissions from fossil fuel power plants, while also helping address emissions in hard-to-abate sectors like steel, cement and aviation – potentially even creating negative emissions (removing more CO2 than it emits into the atmosphere).
Carbon dioxide captured from smokestacks is transported under high pressure through pipelines for injection and permanent underground storage, similar to what the oil industry has been using since 1972 for enhanced oil recovery (EAR), with large-scale CCS projects currently in the works.
CCS could become part of our energy mix in the near future by combining it with renewable technologies like wind and solar to produce low-carbon power even when sunlight or wind don’t exist. CCS could also help lower greenhouse gas emissions from bioenergy sources while providing additional power when needed; this would be known as BECCS or CCUS.
What are the drawbacks of CCS?
CCS presents two primary drawbacks. One is that it merely diverts CO2 emissions from entering the atmosphere while fossil fuels continue to pollute it, while two is that CCS requires massive energy infrastructure such as pipelines, compressors and injection wells to operate effectively.
CCS also incurs high upfront costs, decreases power plant efficiency and allows CO2 buried to seep out during transport or eventually leak out over time.
Proponents of carbon capture storage (CCS) often claim it can reduce CO2 emissions by 85-95%; however, studies have demonstrated much lower reduction rates; even Chevron’s Gorgon project, the world’s largest CCS project, failed to reach its carbon capture goals.
CCS presents risk to frontline communities. To operate effectively, this technology requires pipelines, injection wells and power plants–not to mention other dangerous infrastructure–along with multiple facilities on rural or coastal sites chosen as sites for CCS installations. Unfortunately, such industries disproportionately affect these populations already.