Carbon capture: Meaning, Criticisms & Real-World Uses

What Is Carbon Capture?

Carbon capture refers to technologies and processes that prevent large quantities of carbon dioxide (CO2) from entering the atmosphere, typically by capturing it from industrial sources or directly from the air. This process is a key component within the broader field of Environmental Finance and plays a role in strategies aimed at mitigating Climate Change. The captured carbon dioxide can then be transported and permanently stored underground, or utilized in various industrial applications. The overarching goal of carbon capture is to reduce greenhouse gas emissions, particularly from significant point sources like power plants and heavy industries, thereby contributing to global decarbonization efforts.

History and Origin

The foundational concepts behind carbon capture technologies emerged in the mid-20th century, primarily within the oil and gas industry. Early applications involved injecting carbon dioxide into oil fields to enhance oil recovery, a practice that increased crude oil extraction by boosting reservoir pressure²³. This technique, known as Enhanced Oil Recovery (EOR), demonstrated the viability of underground CO2 injection. While initially driven by economic motives, the environmental implications of CO2 management began to gain attention.

The idea of using carbon capture to reduce industrial emissions for environmental purposes was suggested in 1977 by Italian physicist Cesare Marchetti. Small-scale demonstrations followed in the early 1980s, with economic evaluations appearing in the early 1990s. A significant milestone was reached in 1996 with the commissioning of the Sleipner gas field in Norway, which was the first large-scale project to inject and store CO2 in a dedicated geological formation. This demonstrated the practical application of storing CO2 underground to prevent its atmospheric release. The world's first large-scale coal-fired power plant equipped with carbon capture and storage (CCS) technology, the Boundary Dam Power Station in Saskatchewan, Canada, became operational in 2014, aiming to cut carbon dioxide emissions by up to 90% from one unit.²²,²¹

Key Takeaways

Carbon capture technology focuses on separating and capturing carbon dioxide from industrial emissions or directly from the atmosphere.
The captured CO2 is then typically transported for long-term geological storage or utilized for various purposes, such as enhanced oil recovery.
Carbon capture aims to reduce greenhouse gas concentrations in the atmosphere, supporting global efforts to combat climate change.
The development and deployment of carbon capture projects face significant challenges, including high costs, energy intensity, and infrastructure requirements.
Governmental policies and Financial Incentives play a crucial role in encouraging the adoption and scaling of carbon capture technologies.

Interpreting Carbon Capture

Carbon capture represents a technological pathway within broader environmental and energy strategies. Its interpretation hinges on understanding its role in a diversified approach to emission reduction, alongside other methods like transitioning to Renewable Energy sources and improving Energy Efficiency. When evaluating carbon capture projects, analysts often consider factors such as the volume of CO2 captured, the energy required for the capture process, the security and permanence of storage, and the overall cost per tonne of CO2 avoided. Effective carbon capture implementation is seen as essential for "hard-to-abate" sectors—industries where CO2 emissions are an inherent part of the production process and are difficult to eliminate through other means.

Hypothetical Example

Consider a large cement manufacturing plant, a sector known for significant CO2 emissions. Traditionally, the process of producing cement releases a substantial amount of CO2 directly into the atmosphere. To mitigate this, the plant decides to implement a carbon capture system.

Capture: The plant installs post-combustion carbon capture equipment. This technology captures CO2 from the exhaust gases of the cement kilns before they are released. Chemicals called solvents absorb the CO2 from the flue gas.
Separation: The CO2-rich solvent is then heated, which releases the pure CO2 gas and regenerates the solvent for reuse.
Compression and Transport: The separated CO2 is compressed into a dense fluid. A dedicated pipeline is constructed to transport this compressed CO2 to a nearby geological storage site, such as a deep saline aquifer. This requires significant Infrastructure Investment.
Storage: The CO2 is injected deep underground into the porous rock formation, where it is permanently trapped beneath layers of impermeable rock, preventing its return to the atmosphere.

Through this carbon capture process, the cement plant can significantly reduce its carbon footprint, continuing its operations while contributing to environmental goals.

Practical Applications

Carbon capture is finding practical applications across various industrial sectors, particularly those with high CO2 emissions that are challenging to decarbonize entirely through other means.

One primary application is in the power generation sector, where carbon capture technologies can be integrated with fossil fuel power plants (e.g., coal and natural gas) to capture CO2 before it enters the atmosphere. For instance, the Boundary Dam Power Station in Canada demonstrates the application of carbon capture in a coal-fired power plant,.²⁰
¹⁹
Beyond power, heavy industries such as cement production, steel manufacturing, and chemical plants are increasingly exploring carbon capture as a critical tool for reducing their emissions,.¹⁸ ¹⁷These industries often have process emissions that are difficult to eliminate through electrification or fuel switching alone.

Governments worldwide are also providing significant Public Policy support and financial incentives to accelerate the deployment of carbon capture. In the United States, for example, the Section 45Q tax credit offers substantial incentives for companies that capture and permanently store CO2, with the value of these credits significantly increased by the Inflation Reduction Act of 2022,.¹⁶ ¹⁵This policy aims to stimulate investment and deployment in carbon capture, utilization, and storage (CCUS) projects across various industrial sectors.
¹⁴

Limitations and Criticisms

Despite its potential, carbon capture faces several significant limitations and criticisms that affect its widespread adoption and cost-effectiveness. A primary concern is the high cost associated with implementing and operating carbon capture technologies. Capturing CO2, particularly from dilute gas streams like those from power plants, is energy-intensive and can significantly increase the operational costs and energy consumption of a facility,.¹³ ¹²This added energy requirement can sometimes lead to an increase in overall fuel consumption and associated emissions, diminishing the net benefit.

¹¹Another challenge is the scalability and technical complexity of projects. While small-scale implementations have existed for decades, scaling carbon capture to meet global emissions reduction targets presents substantial engineering and logistical hurdles,.¹⁰ ⁹There are also concerns about the long-term safety and permanence of CO2 storage in geological formations, although extensive research and monitoring are conducted to ensure integrity. Some critics also argue that focusing on carbon capture could detract from investments in more proven and cost-effective Technological Innovation for emissions reduction, such as direct electrification and Renewable Energy. ⁸The International Energy Agency (IEA) has noted that carbon capture has a history of slow deployment and "unmet expectations," with almost all current operational projects connected to the production or use of oil and gas.
⁷
Furthermore, regulatory frameworks and public acceptance remain critical considerations. Questions persist regarding the allocation of Risk Management associated with potential leakage from storage sites and the establishment of clear liabilities. Public perception can also be a challenge, with some stakeholders viewing carbon capture as a means to extend the lifespan of fossil fuel industries rather than a true solution for decarbonization.

Carbon Capture vs. Carbon Sequestration

While often used interchangeably, "carbon capture" and "carbon sequestration" refer to distinct, yet related, aspects of managing atmospheric carbon dioxide.

Carbon Capture specifically describes the process of separating CO2 from other gases at large industrial sources, or directly extracting it from ambient air. It is the initial step in preventing CO2 emissions from reaching the atmosphere. Technologies like post-combustion capture, pre-combustion capture, and direct air capture fall under this category.

Carbon Sequestration, on the other hand, is the broader process of capturing and storing atmospheric carbon dioxide. I⁶t refers to the long-term containment of CO2 to prevent its release into the atmosphere. This can occur through natural biological processes (e.g., absorption by forests or oceans) or through engineered geological processes, where captured CO2 is injected deep underground into suitable rock formations for permanent storage. The U.S. Geological Survey (USGS) defines carbon sequestration as "the process of capturing and storing atmospheric carbon dioxide."

⁵In essence, carbon capture is the "how to get it" part, while carbon sequestration is the "where to put it" part. Carbon capture is a component of engineered carbon sequestration or the larger Carbon Capture, Utilization, and Storage (CCUS) framework. Therefore, while all carbon capture aims for some form of sequestration (storage), not all forms of carbon sequestration involve technological carbon capture (e.g., natural forest growth also sequesters carbon).

FAQs

What is the primary purpose of carbon capture?

The main purpose of carbon capture is to reduce the amount of carbon dioxide (CO2) released into the atmosphere from large industrial sources like power plants and factories. By capturing CO2, it can be prevented from contributing to greenhouse gas accumulation and Climate Change.

Where is captured carbon dioxide stored?

Captured carbon dioxide is primarily stored in deep underground geological formations. These can include depleted oil and gas reservoirs, deep saline aquifers, or unmineable coal seams. The goal is to safely and permanently contain the CO2 to prevent its escape back into the atmosphere.

Is carbon capture a new technology?

The underlying technologies for capturing CO2 have been around for many decades, often used in industrial processes like natural gas purification. However, the application of these technologies specifically for large-scale climate change mitigation, known as Carbon Capture and Storage (CCS) or Carbon Capture, Utilization, and Storage (CCUS), has gained significant traction and development more recently, particularly in the last few decades.,
⁴
³### How does carbon capture relate to sustainable investing?
Carbon capture is relevant to Sustainable Investing as it offers a potential solution for industries with significant emissions to reduce their environmental impact. Investors interested in Environmental, Social, and Governance (ESG)) factors may consider companies investing in or developing carbon capture technologies as part of their efforts towards a lower-carbon economy and achieving Net Zero emissions.

What are the main challenges for carbon capture?

Key challenges for carbon capture include its high cost, the significant energy required for the capture process, and the need for extensive infrastructure for transport and storage. Public perception and regulatory complexities also pose hurdles to widespread adoption.,[²¹](https://www.pipeline-conference.com/abstracts/carbon-capture-utilisation-and-storage-what-are-real-challenges-costs)