Carbon capture and storage (CCS) technologies play a critical role in combatting climate change. CCS technologies reduce emissions from coal-fired power plants and other industrial facilities by sequestering CO2 before it enters the atmosphere.
CCS involves the capture and storage of CO2, an emitter of greenhouse gasses. Saline formations underlying much of the United States offer potential storage sites that could absorb large volumes of CO2. Furthermore, CCS may be used to enhance oil recovery (Enhanced Oil Recovery (EOR).
What is CCS?
Carbon capture and storage (CCS) technology is an important tool in helping create a low-carbon energy future. By collecting CO2, CCS reduces emissions from power plants as well as industrial processes like steel production by sequestering it underground for later release.
CCS is one of the few technologies capable of decarbonizing heavy industry and power generation while being cost-effective and scalable; without CCS reaching our global target of 2degC or less warming will be impossible.
Captured CO2 is transported to storage sites via pipeline or ship for longer distances, then injected into deep geological formations such as depleted oil and gas reservoirs, coal seams or saline aquifers.
Certain projects take the next step and capture carbon directly from the air using negative emissions or direct air capture (DAC) techniques. This may involve harvesting grasses and wood for photosynthesis to remove CO2, then burning it at power plants for electricity production – with any captured CO2 then stored.
How does CCS work?
Once collected, CO2 is transported via pipeline – or ship in some cases – from where it was captured to locations for permanent storage such as saline aquifers or depleted oil and gas reservoirs.
CCS must be combined with policies that increase demand while decreasing costs, such as carbon pricing, public investment and subsidies, clean energy standards that credit companies generating electricity or other forms of energy using CCS, or carbon capture and sequestration credits for use of CCS technology in energy production facilities. Such policies must exist so CCS can play its full role in combatting global warming.
CCS requires extensive energy, making plants with CCS typically more energy intensive than their fossil fuel counterparts. This increases “upstream” environmental impacts of these plants such as coal mining and transportation emissions from fuel use in these facilities, among others. Due to these limitations, CCS should only play a limited role in efforts to combat climate change; technologies like solar/wind power or electrification are likely to be more successful at mitigating emissions than CCS alone.
Why is CCS important?
Fossil fuels remain an integral component of global energy systems and the transition towards renewables may take a while. CCS can speed this transition by making decarbonization of carbon-intensive industries such as power generation, steel production, cement manufacture and ammonia more cost-effective and easier for carbon intensive sectors like power production and steel mills.
Post-combustion capture uses chemical solvents to separate CO2 from flue gas emissions, then compresses and transports it for storage via pipeline, trucks, ships or even drones if necessary. Once at its destination it’s then injected into geological formations such as depleted oil and gas reservoirs or saline aquifers for underground permanent storage.
Bioenergy with Carbon Capture and Storage (BECCS), also known as pre-combustion capture technology, converts biomass into energy while simultaneously removing CO2 from the atmosphere during combustion – known as negative emissions energy production.
What are the benefits of CCS?
Today, carbon capture and storage (CCUS), more commonly referred to as CO2 Capture, Utilization, and Sequestration, facilities around the world store approximately 45 million tons of emissions annually. Climate models suggest CCUS could capture much larger volumes thereby helping achieve long-term climate goals.
CO2 can be captured using various technologies at power plants and other facilities. Post-combustion CCS, which removes CO2 from flue gas after fuel has burned, is one of the more prevalent techniques. Pre-combustion CCS and oxy-fuel combustion systems – in which fossil fuels are burned with pure oxygen instead of air – produce gases composed largely of CO2 and water as waste products.
Transport of CO2 then occurs via pipelines similar to those used to move oil or natural gas over long distances. Companies that capture and store carbon in the United States receive a national tax credit under Section 45Q of the Internal Revenue Code.