Introduction: The Impact of Co2 and the Pursuit of Net Zero through CCUS

Carbon dioxide (CO2) is a major greenhouse gas that significantly contributes to global warming. The excessive release of CO2 from industrial activities and fossil fuel combustion leads to an enhanced greenhouse effect, causing global warming and extreme weather events. 

As the world strives towards achieving net zero emissions—a state where CO2 emissions are balanced by removal from the atmosphere—innovative methods like Carbon Capture, Utilization, and Storage (CCUS) are crucial.

 CCUS involves capturing CO2 emissions, utilizing them in industrial processes, or storing them in geological formations to prevent their release into the atmosphere. One pioneering project that has shown the world a viable path forward is the Sleipner Carbon Capture and Storage (CCS) project.

The Sleipner CCS Project: A Groundbreaking Initiative

The Sleipner CCS project, offshore Norway, is the world's first large-scale initiative to reduce CO2 emissions through carbon capture and storage (CCS).

The Sleipner CCS project, launched on September 15, 1996, as part of a gas field development, has surpassed 20 years of successful operation and continues to run effectively to this day.

(source  https://www.ice.org.uk , https://www.lyellcollection.org)

Over the years, Sleipner has securely stored millions of tons of CO2, demonstrating that this technology is both feasible and effective.

Why Was this Project Initiated?

The Sleipner project was initiated due to the need to reduce CO2 levels in natural gas extracted from the Sleipner vest gas field, which contained about 9% CO2. To meet commercial specifications, this concentration had to be significantly lowered.

(source  https://www.ice.org.uk)

Additionally, in 1991, the Norwegian government introduced a CO2 emissions tax to curb greenhouse gas emissions from offshore oil and gas activities. The tax provided a strong economic incentive for Statoil (now Equinor), the company operating the Sleipner project, to implement CCS technology and avoid hefty penalties. Statoil is a Norwegian state-owned multinational energy company known for its efforts in pioneering energy technologies and sustainable practices.

CO2 Capture

The CO2 was captured using a conventional amine process (monoethanolamine, MEA), effectively separating it from the natural gas.

Monitoring CO2 Storage

Sleipner introduced a comprehensive monitoring program to ensure CO2 is stored safely over the long term. This included methods like seismic surveys, gravity monitoring, and studies of the seabed and marine environment. Some of these programs received funding from the EU, Norway, and other international organizations to help develop new technologies for CO2 storage.

CO2 behaviour underground

When CO2 is injected into the Utsira sandstone formation at Sleipner, it enters a deep, porous, and saltwater-filled geological layer about 800 meters below the seabed. The Utsira formation acts as a storage reservoir, while a thick, impermeable rock layer above it serves as a natural seal, preventing the CO2 from escaping.

Once injected, the CO2 behaves predictably due to the properties of the sandstone and the surrounding environment. The key processes include:

1. Buoyancy Movement:
   CO2, being less dense than the saltwater in the sandstone, tends to rise upwards within the formation. However, it is trapped beneath the impermeable caprock, which stops it from reaching the surface.
2. Dissolution:
   Over time, some of the CO2 dissolves into the surrounding saltwater, forming a denser solution that sinks deeper into the formation. This process reduces the likelihood of the CO2 migrating upward.
3. Residual Trapping:
   As the CO2 moves through the porous rock, small amounts become trapped in tiny pore spaces within the sandstone. This creates additional stability and limits its mobility.
4. Mineralization:
   In the long term (over thousands of years), the CO2 can chemically react with the minerals in the rock, forming stable carbonate compounds. This permanently locks the CO2 in place.

Monitoring studies, such as seismic surveys and gravity field measurements, have tracked these behaviors and confirmed that the CO2 is behaving as expected. These findings have built confidence in the reliability and safety of geological storage as a solution for reducing greenhouse gas emissions.

Recognition and Achievements of the Sleipner Project

Since its launch in 1996, the Sleipner project has continuously operated and expanded to process and store CO2 from nearby gas fields. Statoil, along with partners ExxonMobil, Total, and Lotos, has worked with research organizations to prove the feasibility of long-term CO2 storage.

The project has received widespread recognition for advancing CCS technology. It earned the Carbon Sequestration Leadership Forum (CSLF) Global Achievement Award in 2011. The Inter-Governmental Panel on Climate Change (IPCC) reports of 2007 (AR4) and 2014 (AR5) have used the Sleipner CCS project as a landmark to inspire and inform action on climate change mitigation

By 2016, Sleipner had stored a cumulative total of 16 million tons of CO2 in the Utsira sandstone formation. Combined with 4 million tons stored by the Snøhvit project in northern Norway. (source  https://www.ice.org.uk)

Norway reached a milestone of over 20 million tons of CO2 stored in the first 20 years of Sleipner’s operation. This solidifies Norway’s leadership in developing effective CCS solutions to combat climate change.

Sleipner and the Future of CCS Initiatives

Since starting CO2 injection in 1996, many other industrial-scale CCS projects have emerged worldwide. However, Sleipner remains unique and continues to strengthen CCS efforts globally. It is often said that "the world needs a thousand Sleipners" to tackle climate change effectively.

Looking ahead, the lessons learned from Sleipner are being applied to new, next-generation CCS projects, including those in Norway. Future developments aim to lower costs, improve technologies, and expand CO2 storage capabilities. 

Sleipner will remain a key part of this growing industry, helping to pave the way for more widespread CCS adoption and further climate change mitigation efforts.

Next Generation of CO2 Capture: Saline Aquifers

The Norwegian government has completed feasibility studies for a new large-scale CCS project. CO2 captured from onshore industrial sites will be transported by ship and stored in offshore saline aquifers. This next-generation project will build on Sleipner’s success, focusing on lowering costs and using new technologies for more efficient CO2 storage.

Conclusion: A Beacon of Hope

The Sleipner CCS project is a landmark achievement in the fight against climate change. It has demonstrated that CO2 can be captured and stored safely and effectively, providing a blueprint for future CCS projects around the world. As we look to the future, the lessons learned from Sleipner will continue to inspire and guide efforts to reduce CO2 emissions and protect our planet for generations to come.

By embracing innovative technologies like CCUS and fostering strong public-private partnerships, we can build a sustainable, low-carbon future. The success of the Sleipner project is a powerful reminder that with determination and collaboration, we can overcome even the most daunting environmental challenges.

Desapex Learnings & How We Can Help

The Sleipner CCS project shows that early action, smart technology, and strong policies drive real progress toward net zero. At Desapex, we believe businesses must proactively adopt sustainable solutions rather than wait for regulations to force change.

We help companies achieve their net-zero goals through energy consulting, carbon reduction strategies, and digital engineering solutions. From optimizing building performance with BIM to implementing energy-efficient infrastructure and sustainable materials, we provide the expertise needed to reduce emissions while improving operational efficiency.

By applying lessons from pioneering projects like Sleipner, Desapex empowers businesses to integrate sustainability into their core operations ensuring compliance, cost savings, and a competitive edge in a low-carbon future. Let’s build a sustainable tomorrow, together.