Carbon Capture Usage Storage (CCUS)

Mains Syllabus: GS III - Environmental Pollution and Degradation

Why in the News?

India has introduced several initiatives to achieve net-zero emissions by 2070 - one of which is the emphasis on harnessing Carbon Capture Usage Storage (CCUS) technology.

What is Carbon Capture Usage Storage (CCUS)?

• CCUS – It refers to an array of technologies designed to capture carbon dioxide (CO₂) emissions from large point sources such as thermal plants, oil refineries, and the steel and cement industries.
• The captured CO₂ is either transferred into the earth or reused for industrial applications in various forms.

CCUS (Carbon Capture, Utilization, and Storage) was a prominent topic at COP28, the UN Climate Change Conference held in Dubai in 2023.

• Stages of CCUS - CCUS technology comprises three stages of capture, utilisation and storage.
• First stage ( Capture) - There are different types of carbon capture technologies, and their use is determined by the nature of the gas stream and the intended application.
  • Chemical-solvent based -  It is used when the gas streams contain lower concentrations of CO₂.
  • Physical solvent methods – It is preferred for gas streams with relatively higher concentrations of CO₂.
  • Adsorption techniques – This is used to capture carbon when gas streams contain moderate CO₂ concentrations such as Steam Methane Reforming (SMR) flue gas.
• Second Stage ( Utilization) – In this stage, the captured carbon is converted into value-added products such as green urea, dry ice, carbonated drinks, building materials and chemicals.
• Third stage ( Storage) – It entails storing the CO₂ in saline aquifers, depleted oil and gas fields, and other similar geological formations.

What are the potentials of CCUS?

• Direct Emissions Reduction - CCUS captures CO₂ at the source—before it enters the atmosphere.
• Decarbonisation of Industrial Sector - CCUS has tremendous potential for reducing emissions in hard-to-abate sectors such as coal, steel, cement, oil refineries, which form the backbone of Indian industry.
• Access to Renewable Fuels - The captured CO₂ can be converted into green fuels such as hydrogen, green ammonia, methane, etc.
• Transition to Cleaner Energy - CCUS also plays an important role in facilitating the transition to cleaner energy sources and complementing options like solar and wind power.
• Climate Change Mitigation - By reducing the amount of greenhouse gases released, CCUS helps slow the pace of global warming.
• Job Creation - The deployment and operation of CCUS facilities can generate significant employment opportunities in construction, operation, and the broader supply chain.

What are the challenges in CCUS?

• High Costs - CCUS requires substantial upfront investment for capture equipment, transportation infrastructure (like pipelines), and secure storage facilities.
• Technical Challenge - Direct Air Capture (DAC),  a method that captures carbon directly from the air regardless of the source or concentration – is in its nascent phase.
• Not enough Investment - Since CCUS technology remains a niche area, it has yet to attract significant businesses and investors.
• Infrastructure Challenges - Transporting CO₂ safely requires specialized pipelines, which are expensive to build and maintain.
• Existing oil and gas pipelines are generally unsuitable, and impurities in CO₂ can cause pipeline damage.
• Storage Challenge - Identifying suitable geological storage sites is complex, time-consuming, and costly.
• Not all regions have adequate storage capacity, and some sites may be remote from emission sources, increasing transport costs.

What lies ahead?

• India is preparing to launch a national CCUS mission to decarbonize hard-to-abate sectors like power, steel, and cement.
• Viability gap funding (VGF), production-linked incentives (PLI), tax credits are needed to encourage investment in the sector.
• Clear regulations for CO₂ capture, transport, utilization, and long-term storage are needed.
• R&D Support to advance CCUS technologies, improve capture efficiency, reduce costs, and develop innovative CO₂ utilization pathways is needed.

Reference

Indian Express | Carbon Capture Usage Storage Technology