What is Carbon capture and storage: CCUS 101

The benefits of carbon capture and storage, along with carbon capture utilization and storage, are significant in the global effort to reduce carbon emissions. Understanding why carbon capture is important helps highlight its role in achieving the importance of decarbonization for a sustainable future. Some of the key advantages include:

· Reduces industrial emissions:
Carbon capture and storage helps reduce carbon dioxide from high-emission sectors like cement, steel, and power generation. This lowers their environmental impact without needing to shut them down.

·  Works with existing infrastructure:
Carbon capture technology can be retrofitted into existing plants. This makes it more cost-effective compared to replacing entire systems with new low-carbon alternatives.

·  Supports energy security:
Countries can continue using their existing energy mix while lowering emissions. This reduces reliance on imported fuels and supports stable energy access.

·  Enables carbon utilization:
Captured carbon can be turned into valuable products such as concrete, fuels, plastics, or even used to enhance oil recovery. This creates circular economy benefits.

·  Creates new jobs and economic opportunities:
CCUS projects generate jobs in construction, engineering, operations, and research. The growth of this sector can support local economies and attract clean tech investments.

·  Protects ecosystems and air quality:
By preventing carbon from reaching the atmosphere, carbon capture and storage helps reduce the risk of rising temperatures, ocean acidification, and biodiversity loss.

·  Helps meet international climate targets:
Global agreements like the Paris Accord rely on technologies like CCUS to limit temperature rise. It is often listed as essential in national climate roadmaps.

· Supports innovation and R&D:
Investment in carbon capture technology drives innovation in materials science, clean fuels, and energy efficiency, leading to long-term climate solutions.

Many people use the terms CCUS and CCS as if they mean the same thing. The terms CCUS and CCS are often used interchangeably, but there is a clear difference between the two.

Carbon capture and storage (CCS) focuses only on capturing carbon dioxide from industrial or power plants and storing it safely underground. The main goal is to prevent CO₂ from entering the atmosphere and contributing to climate change.

Carbon capture, utilization and storage (CCUS) goes one step further. After capturing the carbon, it can either be stored underground or put to use in making new products. This “utilization” part can involve turning captured carbon into fuels, chemicals, building materials, or other useful items.

Carbon capture, utilization and storage uses several technologies and applications to reduce carbon dioxide emissions. These methods capture carbon from the air or industrial sources, and then either store it safely or turn it into useful products. Here are the main types of technologies and applications:

• Post-combustion capture:
  This method captures carbon dioxide from the gases released after burning fossil fuels in power plants or factories. Chemicals called solvents absorb CO₂ before it escapes into the air. It can be added to existing plants but can require a lot of energy.
• Pre-combustion capture:
  In this process, fossil fuels are treated before burning. The fuel is converted into a mix of hydrogen and carbon dioxide. The CO₂ is captured, and the hydrogen can be used as a clean fuel. This technology is often used in industrial settings.
• Oxy-fuel combustion:
  Fossil fuels are burned in oxygen instead of air. This creates a gas mixture mostly made of CO₂ and water vapor, making it easier to separate and capture the carbon dioxide.
• Direct air capture (DAC):
  This technology captures carbon dioxide directly from the atmosphere. It uses chemical processes to pull CO₂ from the air, which has a much lower concentration than emissions from power plants. DAC is still developing but could help remove past emissions from the air.
• Membrane separation:
  This newer method uses membranes that act like filters to separate carbon dioxide from other gases. It can be energy-efficient and is being studied for different industrial uses.
• Chemical looping:
  A promising technology where oxygen is supplied to fuel without direct contact with air, capturing CO₂ more efficiently. It is still in research stages.
• Bioenergy with Carbon Capture and Storage (BECCS):
  This method captures carbon from burning biomass (plants or waste). Since plants absorb CO₂ when growing, capturing it after burning can lead to negative emissions, meaning it removes more carbon from the air than it adds.

Carbon utilization applications include:

• Turning captured carbon into building materials like concrete or aggregates, which can reduce emissions in construction.
• Producing synthetic fuels or chemicals that can replace fossil-based products.
• Creating plastics and polymers using CO₂ as a raw material.
• Using CO₂ for enhanced oil recovery (EOR), where it is injected into oil wells to extract more oil. While this extends fossil fuel use, it also stores carbon underground.
• Exploring newer uses such as growing algae for biofuels or food supplements with captured CO₂.

Storage applications:

• Saline aquifers:
  Deep underground porous rock formations filled with salty water. These formations can store large amounts of carbon dioxide safely for thousands of years.
• Depleted oil and gas reservoirs:
  Old oil and gas fields that have been emptied can hold CO₂ underground. These sites are well understood and monitored.
• Basalt formations:
  Certain volcanic rocks can chemically react with CO₂ to trap it as solid minerals, offering permanent storage.
• Monitoring and verification technologies are crucial to ensure stored CO₂ does not leak and stays safely underground over time.

Capturing carbon dioxide is a critical part of the carbon capture, utilization and storage process. Various carbon capture methods are used depending on the source of carbon and the available technology. Understanding what is carbon capture technology helps to see how these methods work in practice. The main methods to capture carbon include:

• Absorption:
  This is the most common method. It uses liquid solvents that chemically bind with carbon dioxide when the gas passes through them. The carbon is then separated from the solvent to be stored or used. This method is often used in post-combustion capture.
• Adsorption:
  Instead of liquids, this method uses solid materials like activated carbon or zeolites that attract and hold CO₂ on their surface. When heated, these materials release the carbon dioxide for capture.
• Membrane separation:
  Special membranes act like filters, letting some gases pass while blocking others. CO₂ is separated based on size or chemical properties. This method can be energy-efficient and is being developed for various industries.
• Cryogenic distillation:
  Carbon dioxide is cooled until it turns into a liquid or solid form, making it easier to separate from other gases. This method is more energy-intensive and is usually used when high purity CO₂ is needed.
• Calcium looping:
  This uses calcium oxide to capture CO₂ by forming calcium carbonate. The carbonate is then heated to release pure CO₂ and regenerate calcium oxide for reuse.

Each method has its advantages and challenges. The choice depends on factors like the concentration of CO₂, the source gas, energy requirements, and costs.

Understanding these methods helps industries select the best way to reduce their emissions through carbon capture technology.

India’s journey toward net-zero emissions by 2070 relies not only on renewables but also on technologies like CCUS. Key national agencies such as the Department of Science and Technology (DST) and NITI Aayog play an important role in supporting research, development, and policies that promote CCUS. Their efforts help position CCUS as a practical solution to lower emissions from heavy industries while balancing India’s growing energy needs.

CCUS can complement renewable energy by managing emissions from sectors where clean alternatives are still developing. This combined approach strengthens India’s path to a cleaner and more sustainable energy future.

• Supports India’s clean energy transition:
  CCUS helps reduce emissions from hard-to-decarbonize industries such as cement, steel, and power generation. For example, Tata Steel has been exploring carbon capture technology to reduce CO₂ emissions in steel manufacturing, while Indian Oil Corporation is piloting CCUS projects in its refineries. This supports India’s shift to cleaner energy without disrupting economic growth.
• Helps meet India’s net-zero target:
  India has set an ambitious goal to reach net-zero emissions by 2070. Achieving this will require multiple strategies, and CCUS is a key part of the mix. It allows India to continue using necessary fossil fuels while cutting carbon emissions.
• Improves energy efficiency:
  By capturing and reusing carbon, industries can improve resource use and reduce waste. This contributes to more sustainable industrial processes.
• Creates new business opportunities:
  Utilizing captured carbon to produce synthetic fuels, chemicals, or building materials opens new markets and generates jobs. Projects like the Oil and Natural Gas Corporation’s (ONGC) CCUS initiatives in Gujarat are examples of how CCUS can foster economic growth.
• Strengthens energy security:
  CCUS enables continued use of domestic fossil fuel resources while reducing environmental impact. This lowers dependence on energy imports and helps stabilize supply.
• Aligns with India’s climate policies:
  The Indian government is encouraging research, pilot projects, and investments in CCUS as part of its climate and energy plans. This support will be vital for scaling the technology.

Incorporating CCUS into India’s renewable energy landscape will be crucial for balancing growth, sustainability, and climate goals. In the next section, we will look at the policies that guide CCUS development globally and in India. 

The development and deployment of CCUS technologies depend heavily on policy support and regulations. International organizations such as the International Energy Agency (IEA) and the Global CCS Institute provide guidance, data, and frameworks that help countries plan and implement CCUS projects worldwide.

In India, government bodies like the Department of Science and Technology (DST), NITI Aayog, and the Ministry of Environment, Forest and Climate Change (MoEFCC) work together to develop policies and funding schemes for CCUS research and projects. These agencies are crucial for creating a supportive environment that can accelerate the adoption of carbon capture technologies in India’s clean energy transition.

Global Policies:

• Many countries have included CCUS in their climate action plans and net-zero strategies.
• Governments offer financial incentives like tax credits, grants, and subsidies to encourage investment in carbon capture technology.
• International organizations promote knowledge sharing, research, and collaboration to speed up CCUS deployment.
• Some regions have created carbon pricing or emissions trading systems, which make it more cost-effective for companies to reduce emissions through CCUS.

India-Specific Policies:

• India’s government recognizes CCUS as a key technology to meet its climate targets and is promoting research and pilot projects.
• The Department of Science and Technology (DST) and other bodies have set up programs to fund CCUS innovation.
• Policies focus on integrating CCUS with renewable energy growth and industrial decarbonization.
• India is also engaging with international partners to build capacity and bring in global best practices.
• While regulations for CO₂ storage and transportation are still developing, the government is working to establish clear guidelines.

Strong policies and support systems are essential to overcome challenges like high costs and infrastructure gaps. With growing attention worldwide, CCUS is becoming an important part of climate and energy policies.

In the next section, we will explore global and India-specific CCUS projects that show how this technology is being put into action.

Carbon capture, utilization and storage is no longer just an idea, it is being put into action around the world and in India through various projects. Many CCUS projects worldwide receive backing from international coalitions such as the Oil and Gas Climate Initiative (OGCI) and support from agencies like the IEA. These projects demonstrate how carbon capture technologies can be scaled to reduce emissions from industries and power plants.

In India, CCUS projects often collaborate with national agencies like the Department of Science and Technology (DST) and are influenced by strategic plans from NITI Aayog. This partnership between government and industry is vital to building the infrastructure and technical expertise needed for India to meet its ambitious climate targets.

Global CCUS projects:

• Several large-scale CCUS projects operate worldwide, capturing millions of tons of CO₂ annually.
• Projects like Norway’s Sleipner have been safely storing carbon underground since the 1990s.
• The Boundary Dam project in Canada was the first commercial coal-fired power plant to use CCS technology at a large scale.
• In the United States, the Petra Nova project captured CO₂ from a coal plant for enhanced oil recovery.
• The Gorgon CO₂ Injection Project in Australia is one of the world’s largest CCUS operations linked to natural gas production.
• These projects provide valuable lessons on technology, regulation, and economics for future CCUS efforts.

India-specific CCUS projects:

• India has launched pilot projects focusing on carbon capture in industries like cement, steel, and power generation.
• The Tata Steel plant in Jamshedpur has explored carbon capture to reduce emissions from steel production.
• Research institutions and government agencies are partnering to develop CCUS technologies suited to India’s energy mix.
• Projects are also underway to explore carbon utilization, such as using captured CO₂ in concrete manufacturing.
• While India’s CCUS sector is still developing compared to global leaders, interest and investment are growing quickly.

These projects show that CCUS is a practical solution being tested and scaled worldwide. They also highlight the need for continued innovation, funding, and supportive policies.