CO2 Storage and Carbon Hubs: Building the Future

In Brief...

Captured CO₂ can only be permanently prevented from entering the atmosphere through storage in deep geological formations. While CO₂ can be reused in industry and agriculture, these markets are limited and cannot absorb the volumes that would result if carbon capture were deployed at scale.

To make large-scale storage viable, emitters are forming regional clusters that share infrastructure and costs. Central to these systems are carbon hubs—facilities that coordinate the transport and storage of CO₂, often with government support. CO₂ can be moved by pipeline, ship, or train—including across borders—encouraging international partnerships and allowing countries without suitable geology to access storage in neighbouring states.

Key Points
Why is CO2 storage necessary?
What makes a rock formation suitable for CO2 storage?
What are suitable storage locations?
How can we be sure that CO2 stored remains underground?
Transporting CO2 to Storage Sites
Sharing the Costs
Challenges to Overcome
Current Projects
Further Reading and Resources

Key Points

Carbon capture and storage (CCS) involves capturing CO₂ from industrial sources and permanently storing it to prevent its release back into the atmosphere.
Geological storage in deep underground rock formations is the only viable option for permanently sequestering CO₂ on a large scale.
Suitable storage sites must have specific geological characteristics: porous rocks that allow CO₂ to flow in, an impermeable cap above to contain it, and enough capacity to store the required volumes.
Depleted oil and gas fields, which naturally held oil and gas underground for millions of years; saline aquifers, porous rock layers filled with salty water; and basalt formations, volcanic rocks that chemically react with CO₂ to lock it away permanently, are considered the most promising sites for CO₂ storage.
Captured CO₂ will be transported to storage locations by pipeline, ship, or train.
Carbon hubs will provide shared infrastructure for processing, transporting, and storing CO₂ from multiple sources.
CO₂ clusters will be alliances of industrial emitters that collaborate to share costs and risks associated with CCS.
Regional hubs and clusters will encourage more companies to adopt CCS by reducing individual costs and providing access to shared infrastructure, technology and expertise.
CCS infrastructure is likely to require government support and policies that assign economic value to stored CO₂.
Several notable hub and cluster projects are underway globally, including Northern Lights in Norway and the East Coast Cluster in the UK.
Challenges for CCS development include establishing regulations, securing funding, gaining public support, and coordinating stakeholders from different industries.

Why is CO₂ storage necessary?

Capturing CO₂ from industrial emissions will only impact atmospheric concentrations if the captured CO₂ is permanently prevented from re-entering the atmosphere. Currently, the only proven method for permanent storage is geological sequestration — injecting CO₂ deep underground into carefully selected rock formations that can absorb and trap the gas safely over the long term. These sites must possess the characteristics to allow both the injection and secure, long-term storage of CO₂.

What makes a rock formation suitable for CO₂ storage?

Permanent geological storage of CO₂ relies not only on the physical capacity of underground formations, but also on how the CO₂ interacts with the surrounding environment. Once injected deep underground, CO₂ behaves as a dense fluid and can be trapped in several ways. In some formations, such as basalt rock, the CO₂ will react chemically with silicate minerals to form stable carbonate minerals—a process known as mineralisation. In saline aquifers, some of the injected CO₂ dissolves into the salt water, reducing the chance of it migrating back to the surface.

Successful CO₂ storage sites typically meet three key criteria:

Sufficient storage capacity: This refers to the volume of CO₂ that a rock formation can accommodate over time. The greater the capacity, the more emissions a site can safely contain.

High injectivity: Injectivity describes how easily CO₂ can be introduced into the rock formation. It is influenced by the rock’s permeability (how readily fluids can flow through it) and porosity (how much void space is available to hold the CO₂). High injectivity enables efficient injection, reducing the pressure needed and the energy required for compression.

Strong containment capability: A secure storage site must be overlain by a layer of caprock—an impermeable barrier that acts as a seal, trapping the CO₂ below and preventing it from migrating upwards.

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What are suitable storage locations?

Depleted oil and gas fields are underground rock formations which once contained hydrocarbons before they were extracted by oil companies, proving their ability to trap liquids and gases for millions of years. Since they were studied in detail by oil companies during exploration and operation, their geology is well understood, with permeable rock structures for storage and an impermeable caprock that seals in CO₂.
Many sites already have wells drilled for oil and gas extraction, which can often be adapted for CO₂ injection. In some cases, these fields are also connected to industrial sites via pipelines.
Saline aquifers are deep, porous rock formations containing brine (concentrated saltwater) that are widespread around the globe and offer large storage potential. At these depths, high pressure keeps CO₂ in a dense, fluid-like state that spreads easily through the rock. Additionally, CO₂ can react with the saline water and surrounding minerals, gradually forming stable, solid compounds that will lock it away for millions of years.
Basalt rock formations: These are volcanic rocks rich in minerals that naturally react with CO₂. When injected, the CO₂ reacts to form stable minerals, locking it permanently into the rock

How can we be sure that CO₂ stored remains underground?

To ensure that CO₂ injected into deep rock formations remains securely stored and has not escaped or migrated to less secure neighbouring formations, long-term monitoring will be required. Scientists can use a variety of techniques to track and verify the behaviour of stored CO₂:

Seismic imaging, to track the movement of CO₂ underground.
Pressure sensors, to detect changes in the storage formation.
Surface sensors, to identify any leaks to the atmosphere.

Who will be responsible for the stored CO₂?
Regulatory frameworks are still evolving in many regions to determine the long-term responsibility for sequestred CO₂. A possible scenario is that the company or organization handling the captured CO₂ will be responsible for its transportation and injection into underground location. They will then be expected to monitor the stored CO₂ for a period of time, perhaps 10-20 years, after which responsibility will pass to the national government.

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Transporting CO₂ to Storage Sites

Most industrial CO₂ sources will not be conveniently located near suitable geological formations for storage. Transporting captured CO₂—often over long distances and sometimes offshore—typically involves one of three options: pipeline, ship, or train.

Pipelines are the most efficient for large, continuous transport over land. They offer high capacity and reliability but require major investment and regulatory approval. Public resistance and land access issues can also present challenges.
Shipping may suit dispersed sources or offshore storage sites, offering flexibility, but with higher operational costs and lower capacity than pipelines.
Rail transport is a viable option where pipeline infrastructure is lacking and volumes are moderate. It can use existing rail networks but is less efficient for large-scale operations.

Sharing the Costs

How will the massive costs be covered?

The infrastructure needed to transport and store CO₂ will be expensive, and large-scale deployment only feasible if the costs are shared. This has led to the development of the concept of carbon hubs and carbon clusters:

Carbon hubs are centralized facilities that collect CO₂ from multiple sources and organize its transport to shared storage sites.
Carbon clusters are groups of industrial facilities built close together because of a common need to be close to natural resources such as coalfields, or the cities which provide the labour force.

What benefits could the development of carbon hubs and clusters offer?
Carbon hubs and clusters can provide several benefits to local communities and the broader economy:

Encouraging wider adoption of carbon capture technology
As financial incentives for CO₂ storage increase through tax breaks or the need to avoid emission penalties, the presence of shared infrastructure will make carbon capture more economically viable, encouraging more local industries to participate.
Improving public awareness
Raising the profile of CCS through the presence of local hubs may lead to broader public understanding and acceptance of the technology.
Developing local expertise
The establishment of carbon hubs and clusters will encourage the growth of specialized knowledge and skills in the local workforce, increasing levels of expertise and attracting further investment.
Employment opportunities
Carbon hubs and clusters could create significant employment opportunities, initially from construction and engineering, then later the jobs related to ongoing operations and maintenance. Other sectors are also likely to benefit through indirect job creation, including areas such as professional services.
New opportunities for industrial regions
In areas that have traditionally relied on fossil fuel industries, carbon capture hubs and industrial clusters could provide new economic opportunities. By making use of existing infrastructure and the skills of the local workforce, these developments may help such regions adapt, without losing the industrial character that has shaped their identity.
Innovation and technology development
Collaboration between industries within carbon hubs and clusters can promote a culture of knowledge sharing, driving innovation, attracting start-ups and research and development (R&D) facilities.
International cooperation
Carbon hubs and clusters, especially those near borders, will encourage international cooperation, and give countries without suitable storage locations the opportunity to storage facilities in neighbouring countries.
Future Hydrogen hubs
The development of carbon hubs and clusters naturally paves the way for cooperation in the establishment of regional hydrogen hubs to accelerate the use of hydrogen as a source of clean energy in industry and transportation.

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Challenges to Overcome

What challenges might regions face when developing carbon capture hubs and clusters?

Regions planning to develop carbon capture hubs and clusters will face a mix of technical, financial and political challenge, including high upfront costs, the need to getting many possibly diverse industries to work forward together, and possibly poorly defined regulations.

High upfront costs
Building the infrastructure for the transportation and storage of CO₂—pipelines, shipping terminals, and geological storage sites—will require major investment well before any returns are seen. Without clear government support in the form of subsidies, tax credits, or contracts that guarantee a minimum price for captured, companies may be reluctant to get involved.

Uncertain policy landscape
In many countries, the rules for CCS are still evolving. Key issues include how projects get approved, who takes long-term responsibility for stored CO₂, and how emissions and removals will be valued—through carbon taxes, emissions trading, or storage incentives. A lack of clarity on these points can stall investment.

Public confidence and local concerns
Even where the technical risks are low, proposals for pipelines or storage sites may raise local concerns about safety and any possible environmental impact. Building trust depends on early, open engagement and clear plans for monitoring and long-term site management.

Coordination and commercial risk
CCS hubs depend on coordination between many players—emitters, transport operators, and the organisations developing storage sites. These groups often have different business models and timelines. For storage and transport providers, one of the biggest risks is a lack of guaranteed CO₂ supply. If planned capture volumes don’t materialise—due to delays, changes in policy or technical problems—then infrastructure built to handle millions of tonnes may be underused, with serious financial consequences.

Workforce and skills
Delivering CCS at scale will require engineers, geologists, project managers and skilled technicians. Much of the practical expertise needed for CCS—such as drilling, subsurface analysis and pipeline operation—draws on skills developed in the oil and gas industry. Where that experience doesn’t exist, regions will need to build up the workforce through training and education.

Keeping pace with capture
If CO₂ capture expands faster than the infrastructure needed to move and store it, bottlenecks can form. That risks holding back emission reductions even when capture technology is available. Coordinated planning is essential to ensure that storage and transport can grow in step with demand.

Current Projects

What large-scale CO₂ storage projects are currently underway?
The most advanced commercial-scale project for storing CO₂ underground is the Northern Lights project in Norway which is developing an open-access CO₂ transport and storage network in the North Sea. CO₂ will be delivered by ship to a terminal at Øygarden, on Norway's southwest coast, and from there sent by pipeline to an offshore storage site. The Northern Lights project aims to demonstrate the viability of an international, large-scale carbon storage hub, offering CO₂ storage capacity to emitters across Europe. This will be particularly important for industries with carbon capture aspirations in countries without suitable geological formations to create their own storage facilities.

For more information about Northern Lights and other storage hubs under development, visit our projects page.

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