Carbon capture and storage (CCS) has become an essential tool in fighting climate change, being part of most mitigation plans that aim to limit warming to 1.5 degrees C or below. CCS deployment plays a central role in these mitigation scenarios.
Process Description: CO2 capture and storage involves collecting CO2 from the atmosphere or large industrial sources (such as coal and gas power plants ) using large scale systems or directly. Once extracted from the air or atmosphere, this CO2 is sent via pipeline to long-term storage locations for long term storage.
Capture
Carbon Capture and Storage (CCS) involves collecting CO2 produced during energy generation such as power plants, cement or steel production or fossil fuel combustion and then transporting and storing it deep underground in geological formations. Unfortunately, CCS technology is currently only widely utilized by utilities.
CO2 emissions from fossil fuel power plants and certain industrial processes (ammonia production or natural gas processing, for instance) are captured, purified, liquefied and transported to be stored at locations worldwide – there are currently 40 operational CCUS projects active globally with 25 under construction and over 300 planned.
Supporters of carbon capture and storage (CCS) argue that attaching it to coal and gas power plants would help mitigate emissions from these sources, yet CCS remains expensive and cannot offer zero emissions solutions – particularly when attached to heavy industry. There are much better ways of reducing our climate footprint, such as transitioning to cleaner energy options or cutting emissions during household, business, or travel activities.
Compression
Carbon capture and storage (CCS) technology is an efficient way to reduce greenhouse gas emissions from power plants and other industrial sources, by collecting CO2 prior to it entering the atmosphere. CCS forms one component of wider technologies known as carbon dioxide utilization and sequestration (CCUS).
Captured CO2 must then be transported to geological storage sites, typically through pipelines; ship transport is also an option but typically more costly. Pipelines require significant energy in order to compress CO2 while keeping pressure and temperatures at the required levels for safe operation.
Once at its storage site, CO2 can be injected into underground geological formations for long-term storage. Structural trapping uses rock layers and faults to stop CO2 migrating laterally or vertically while chemical trapping involves injecting supercritical CO2 into oil or natural gas-saturated formations – the CO2 then can be extracted using similar processes as those employed when creating its capture plant.
Transport
Carbon Capture and Storage (CCUS) involves collecting CO2 from large point sources like power plants or industrial activities like steel or cement production, transporting it via pipeline or ship over long distances, then injecting it deep underground locations such as depleted oil fields or saline aquifers for permanent injection into geological formations such as depleted oilfields or saline aquifers – an essential technology in reaching net zero emissions that works alongside renewables, reforestation and energy efficiency technologies.
CCUS systems are tailored specifically to each facility that emits carbon dioxide, so transporting and storing it requires considerable infrastructure investment that may not always be readily available.
Captured CO2 is often compressed into liquid form before transport, in order to minimize its volume, and conditioned according to transport or storage specifications. Most captured CO2 is transported via pipeline from where it was captured to its storage site; however, liquid CO2 transportation by truck or ship is an option that has been employed at certain project sites where storage sites are more remote from capture sites.
Storage
Carbon capture and storage (CCS) technologies reduce CO2 emissions from power plants or other sources by isolating carbon dioxide from other gases before either permanently storing it underground or using it to generate clean energy. As of today, there are approximately 40 active CCUS projects worldwide with another 25 under construction or some stage of development, totalling over 300 projects overall.
At the site, CO2 is injected into deep geologic formations for permanent storage. Injection involves an extremely controlled process in which rock layers and faults are sealed to prevent CO2 migration into shallower formations or the atmosphere. Common storage sites for CO2 include depleted oil & gas reservoirs, saline aquifers or coal beds.
Structural trapping occurs when CO2 becomes more buoyant than other liquids and migrates upward through porous rocks until reaching an impermeable layer of seal rock which effectively traps it. Regular monitoring must take place to ensure that CO2 remains stored within its storage formation and does not escape to other locations.