What is Carbon Capture and Storage?
CCS is a suite of technologies designed to prevent large amounts of carbon dioxide (CO₂) from being released into the atmosphere. Positioned at the intersection of industrial necessity and technological challenge, CCS is increasingly recognized as an indispensable tool for decarbonizing sectors where emissions are otherwise unavoidable.
Executive Summary
The strategic importance of CCS is underscored by its central role in climate mitigation scenarios of the IEA and IPCC. It's considered virtually the only viable pathway for deep emissions reductions in heavy industries such as cement, steel, and chemicals.
As of early 2025, over 50 million tonnes of annual capture capacity are operational, with the pipeline promising a near nine-fold increase to approximately 430 Mt per year by 2030, driven primarily by policy support like the U.S. Section 45Q tax credit.
Capture
CO₂ is separated from other gases produced by industrial processes, like those at power plants or steel factories, using advanced chemical and physical separation techniques.
Transport
The captured CO₂ is compressed into a supercritical state and transported via dedicated pipelines or specialized ships to carefully selected storage sites.
Storage
The CO₂ is injected deep underground into carefully selected geological formations for permanent storage, secured by multiple trapping mechanisms.
Capture & Storage Techniques
The methods for capturing and storing CO₂ vary based on the industrial source and local geology. The capture process is the most complex and costly part of CCS. Explore the primary techniques used today.
Post-Combustion Capture
This is the most mature and widely deployed capture methodology, where CO₂ is captured from flue gases after the fuel has been burned in a conventional combustion process using air. The process typically uses a chemical solvent to absorb the CO₂, which is then heated to release the pure CO₂ for compression and transport.
Key Technical Details:
Main Advantage:
Retrofitting capability - it can be added to existing power plants and industrial facilities without major modifications to the original combustion process, providing a crucial pathway to decarbonize long-lived assets.
Global Project Status & Pipeline
The global pipeline of CCS projects has grown significantly, driven by stronger climate policies and incentives. While progress is encouraging, the scale-up required to meet climate targets is immense.
Operational Facilities
~51 Mt/year capture capacity currently operational worldwide across various industrial sectors
Total Pipeline
Facilities in all development stages: operational, construction, and planning phases
2030 Projection
Annual capture capacity projected by 2030 (9x current operational level)
Global CCS Facility Development Status
Regional Leadership
North America leads due to strong policy support, particularly the U.S. 45Q tax credit
Landmark Projects
Quest (Alberta, Canada)
1+ Mt/year operational since 2015, >9Mt stored in deep saline aquifer
Northern Lights (Norway)
Cross-border CO₂ transport & storage hub, operational 2025
Porthos (Netherlands)
Rotterdam industrial cluster hub, 2.5 Mt/year from 2026
Economics & Policy Drivers
CCS is capital-intensive and not commercially viable without policy support. The "commerciality gap" between high costs and revenue necessitates government intervention to create the business case.
Cost Structure by Source
Low-Cost Sources
per tonne CO₂
High-purity sources: ethanol fermentation, ammonia synthesis
Medium-Cost Sources
per tonne CO₂
Natural gas power plants, some industrial processes
High-Cost Sources
per tonne CO₂
Coal power, cement, steel (wide range by technology)
*Capture costs dominate, typically 75%+ of total project costs. Transport: $2-14/tonne, Storage: <$10/tonne
Key Policy Drivers
U.S. Section 45Q Tax Credit
- • $85/tonne for geological storage
- • $60/tonne for utilization/EOR
- • Direct pay & transferable credits
- • 73 new facilities announced in 2023
Other Global Policies
- • Canada: 50% investment tax credit
- • EU: €38B Innovation Fund
- • UK: £1B CCS Infrastructure Fund
- • Norway: Direct state funding
Commerciality Gap
CCS requires carbon prices of $25-30/tonne to begin deployment, but EU ETS historically too low. Government subsidies bridge this gap.
Industrial Competitiveness
CCS increases steel costs <10%, while green hydrogen routes increase costs 35-70%. Often the least-cost decarbonization path.
Stranded Assets
Retrofitting with CCS avoids premature retirement of trillions in industrial assets, maintaining operational life in low-carbon world.
Hub Models
Shared transport & storage infrastructure spreads costs across multiple users, reducing per-ton costs and barriers to entry.
Job Creation
U.S. Direct Air Capture industry alone projected to create 300,000+ jobs in construction, engineering, and manufacturing at scale.
Investment Scale
Meeting climate targets requires 70-fold capacity increase by 2040, demanding trillions in investment and stable policy frameworks.
Challenges & Risk Management
While technically mature, CCS faces significant deployment challenges beyond technology, including operational risks, long-term liability, and public acceptance.
Technical Risks
- • Storage security & potential leakage pathways
- • Infrastructure corrosion from CO₂ + water
- • Induced seismicity from pressure changes
- • High energy penalty (reduces plant efficiency)
Legal & Liability
- • Long-term liability (centuries-scale storage)
- • Pore space ownership uncertainties
- • Complex permitting processes
- • Financial assurance requirements
Social License
- • Low public awareness & understanding
- • NIMBY resistance to local projects
- • "False solution" criticism from some groups
- • Trust in operators & regulators
Economic Challenges
- • "Subsidy cliff" when incentives expire
- • High upfront capital requirements
- • Slow cost reduction vs. renewables
- • Project execution risk ("valley of death")
Operational Issues
- • Operating costs growing faster than capacity
- • Underperformance vs. design targets
- • Complex integration with existing plants
- • Long-term monitoring requirements
Infrastructure Scale
- • Pipeline network needs 100x expansion
- • Complex permit acquisition for corridors
- • Coordination across multiple stakeholders
- • Regional hub development challenges
Risk Mitigation Strategies
Technical Solutions:
- Rigorous site characterization & selection
- Advanced monitoring systems (MMV)
- Material selection for corrosion resistance
- Pressure management protocols
Policy & Social:
- Clear liability transfer frameworks
- Early community engagement programs
- Transparent performance reporting
- Long-term policy certainty
Geological & Seismic Impacts
Large-scale CO₂ injection impacts subsurface geology through geomechanical and geochemical processes. Understanding these interactions ensures safe, permanent storage.
Geomechanical Effects
Induced Seismicity Risk
CO₂ injection changes subsurface pressure, potentially affecting pre-existing faults:
Risk Factors:
- • Proximity to critically-stressed faults
- • Injection rate and pressure magnitude
- • Pre-existing stress conditions
- • Geological structure complexity
Reality Check:
- • Most events are micro-seismic (not felt)
- • No large earthquakes from CCS to date
- • Risk is site-specific and manageable
Surface Deformation
Reservoir pressure changes affect rock stress and surface elevation:
Depletion Effects:
- • Oil/gas extraction causes rock compaction
- • Surface subsidence up to 24cm possible
- • Well-documented in many fields globally
Re-injection Effects:
- • CO₂ injection re-pressurizes reservoir
- • Can cause slight surface uplift
- • Monitored using satellite InSAR technology
Geochemical Reactions
CO₂-Rock-Fluid Interactions
1. Acidification
CO₂ dissolves in brine → carbonic acid → lower pH environment
2. Mineral Dissolution
Acidic brine dissolves carbonates & feldspars → increased porosity
3. Precipitation
New minerals form (siderite, clays) → potential permeability changes
Operational Implications:
Positive:
- Enhanced storage capacity from dissolution
- Long-term mineral trapping potential
Challenges:
- Pore throat clogging from precipitation
- Reduced injectivity over time
Comprehensive Monitoring & Modeling
Monitoring Technologies:
- 📡 Seismic Monitoring: Arrays detect micro-earthquakes in real-time
- 🛰️ InSAR Satellite: Millimeter-scale surface deformation detection
- 🔬 Geochemical Sampling: Monitor fluid chemistry changes
- 📊 Pressure Monitoring: Track reservoir pressure evolution
Modeling Approaches:
- ⚙️ Geomechanical: Stress changes & fault stability analysis
- 💧 Fluid Flow: CO₂ plume migration & pressure distribution
- 🧪 Geochemical: Rock-fluid reactions & mineral changes
- 🔮 Predictive: Long-term behavior & risk assessment
Key Findings from Field Experience:
Large earthquakes from dedicated CO₂ storage projects
Projected retention for well-managed sites over 1,000+ years
Years of natural CO₂ accumulation prove storage viability
Scientific Consensus:
While CO₂ injection can induce seismicity and cause geochemical changes, these risks are well-understood and manageable through proper site selection, pressure management, and comprehensive monitoring. The IPCC concludes with "high confidence" that appropriately selected, designed, and managed storage sites can permanently isolate CO₂ from the atmosphere.