The landmark industrial-scale carbon capture and storage project at Sleipner heralds 20 years of successful operations but reveals obstacles to replicating its success.
The pioneering Sleipner carbon capture and storage project has achieved 20 years of successful CO2 storage operations; despite its achievements, barriers like business models, regulatory issues and commercial drivers, could limit the opportunity to repeat its success elsewhere.
About the Sleipner Carbon Capture and Storage project
The Sleipner CCS project offshore Norway is the world's first industrial-scale CCS project for the purpose of carbon emission abatement, and passed the 20-year milestone of operations in 2016.
Sleipner is an industrial project, in which CO2 capture and storage (CCS) was implemented as part of a gas field development.
CO2 injection started on 15 September 1996, and since then a steady stream of insights from this project have been generated and shared with numerous research projects globally, helping to increase confidence and competence in support of this vital greenhouse gas emission reduction measure.
Why was this project initiated?
This project emerged after discussions in 1990 to find a concept solution for the Sleipner West gas and condensate field in the North Sea. The natural gas in the reservoir contains about 9% CO2 and this needed to be reduced significantly to reach commercial specification.
In 1991, the Norwegian authorities introduced a CO2 emissions tax as an effort to reduce greenhouse gas emissions from Norwegian offshore oil and gas activities. The additional investments in order to compress and re-inject the removed CO2 amounted to approximately $100m (USD in 1996).
The CO2 tax was one of the drivers for Statoil's plans to re-inject the removed CO2 into the Utsira sandstone formation. The Norwegian CO2 taxes are applied differently to different industry sectors. Today the offshore industry pays CO2 taxes and quotas under the EU Emission Trading System (ETS). For the offshore oil and gas sector the CO2 taxes and the quota price under ETS is currently around $60 (USD) per ton.
What was unique about this project?
The bold and pioneering business decision to deploy CCS, despite the lack of similar experiences elsewhere, attracted a lot of interest in the project as demonstration of the concept of geological disposal of CO2 captured from industrial activities.
Storage monitoring programme
Because of its novelty, the Sleipner CO2 monitoring programme, which was needed to prove secure long-term storage, has included time-lapse seismic, gravity field monitoring and marine and seabed surveys. Some of these programmes were able to benefit from research funding from the EU, Norway and worldwide in order to develop specific technologies for wider deployment of CO2 storage.
Sleipner as a benchmark
Many lessons learned from this industrial-scale demonstration project became adopted into industry best practice, and experience from Sleipner was used as a guide for the EU Directive on geological storage of carbon dioxide (adopted by the European Parliament in 2009).
Modifications to the London protocol and the OSPAR convention to allow for CO2 storage in offshore geological formations have also used Sleipner as a benchmark.
Geological containment of CO2
In terms of long-term containment, the injected CO2 will remain in the Utsira sandstone for thousands of years, similar to how natural gas and oil have been trapped in these kinds of deep geological formations for millions of years. The Utsira sandstone is a very extensive and highly porous sandstone filled with saltwater (a saline aquifer formation) and the CO2 is trapped under an 800-metre thick layer of ceiling rock preventing any seepage into the atmosphere.
CO2 behaviour underground
The behaviour of the CO2 in the sandstone has been mapped in various research programmes and projects and documented in many publications. Seismic surveys and gravity field measurements have been especially valuable and show that the behaviour of the CO2 underground is in line with the plans established prior to injection.
Developing research on CCS
Statoil has recognized the value of this project for the development of CCS by sharing information and experience from Sleipner with numerous research networks and institutions globally, with the Norwegian institutions SINTEF and NTNU being central to these efforts.
Many technical articles have been published on modelling and monitoring CO2 storage using the data provided from Sleipner, helping to build confidence in the concept of geological storage of CO2 and improving our understanding of the processes involved.
Sleipner heralded a success
The CO2 capture is achieved using a conventional amine process (using monoethanolamine, MEA. Sleipner was the first project to implement this process on an offshore platform.
In continuous operation since 1996, the project will continue past this year's 20-year landmark, and has also begun to process and store CO2 from neighbouring gas fields in the Sleipner area. Statoil, with its partners ExxonMobil, Total and Lotos in the Sleipner Licence and along with numerous research partners are proud of this pioneering CCS project – the first to demonstrate the feasibility of safe long-term storage of CO2 in deep underground formations. The Sleipner CCS project has received global recognition for its contribution to the development of CCS by receiving several technology awards including 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 the Sleipner CCS project had stored 16m tons of CO2 in the Utsira sandstone formation; a deep geological layer near the gas and CO2 processing platform. Together with the addition of 4m tons from the Snøhvit CCS project, offshore northern Norway, this gets Norway past the 20m-tons-stored milestone for the 20 year of CCS operations at Sleipner.
The future of Sleipner and other CCS projects
Since starting injection in 1996, several other industrial-scale CCS projects have emerged (in Norway, Canada, USA, Australia and elsewhere); however, the value of the Sleipner project is quite unique and will continue to be used to strengthen and build up CCS globally. It is often said that "the world needs a thousand Sleipners" to address the climate challenge.
While this ambition is clear, each low-carbon project (including CCS, renewable energy, and hydrogen energy) builds on the experience of previous projects. Sleipner shows that our society can control greenhouse gas emissions from industrial processes and from fossil fuel combustion "brick-by-brick" and project by project. We hope the Sleipner 20-year milestone will inspire others for many years to come.
Next generation of CO2 capture: saline aquifers
The Norwegian Government recently announced completion of feasibility studies for the next large-scale CCS project in Norway, where CO2 captured from onshore industrial sites will be transported by ship and stored in offshore saline aquifers. This next generation project will heavily build on the Sleipner experience and focus on bringing the costs down, using new novel technologies and finding the most cost-efficient ways to construct, operate and monitor the storage of CO2.
Potential future industry
If the Norwegian Government proceed with this next generation large-scale CCS project, it would be an unique opportunity to have a first-of-a-kind industrial CCS value chain where CO2 is transported by ship and stored in an offshore formation.
Barriers to success
For further deployment of CCS, technology and monitoring improvements are needed; however, equally important is to establish business models that balance the risk and reward in such a way that each part of the value chain can attract industrial companies and investors. This will in most cases only be possible if the business models are tailored to the different challenges and opportunities along a value chain.
Government help needed for future CCS
As CCS in the medium term will be in a pre-commercial phase, this will require a strong public-private-partnership structure where Governments take the role as a 'value chain integrator' and guarantor as well as tailor financial support to complement the current low CO2 price.
Twenty years of successful CO2 storage operations could be replicated but barriers like business models, regulatory issues and commercial drivers need to be solved for concrete projects. Industry have shown interest but active and close public-private-partnerships are needed for a wide deployment of CCS.
Further information
- Carbon capture and storage briefing sheet; ICE; 2014
- Electricity transmission and distribution briefing sheet; ICE; 2014
- Marine energy - what are the current options and technologies? briefing sheet; ICE; 2016
- Marine Renewables – Crossing the Valley of Death Recorded lecture; ICE Vernon Harcourt Lecture 2016
- Oil briefing sheet; ICE; 2016
- Ground Engineering training courses; ICE Training;
- Environmental Awareness training courses; ICE Training;
- 'CCS—an ambitious contribution to combat climate change' briefing article, Proceedings of the Institution of Civil Engineers - Energy journal; ICE Publishing; 2007
- The Big Debate 2016: This house believes that the UK energy industry is not fit for purpose to secure a low carbon energy supply, London recorded lecture; ICE; 2016
