A case study looking at the potential for long-term CO2 storage beneath the North Sea

This is the fourth article in a series of five about storage. You can read the previous article, Global Views on CCS and Storage of CO2, here. Article number five will be a description of the most prominent storage sites and projects.

The countries surrounding the North Sea, like Norway and the UK, are already working together to map the possibilities for storing CO2 in the area and to develop common guidelines. The North Sea Basin Task Force, which was established in 2005, delivered a report in 2007 that stressed the importance of CCS as a solution to combat climate change and how barriers should be removed to make it easier for nations to cooperate and store CO2 in the North Sea.

ZERO is also a strong supporter of creating and establishing large storage sites for storing CO2 from multiple sources. Several of the largest potential storage sites are located outside the coast of Norway and ZERO is currently working on suggestions for how these storage sites can be fully exploited.

However, one should first look at the actual potential in the North Sea basin. The Norwegian Petroleum Directorate has created a CO2 Storage Atlas. This atlas only covers the Norwegian Sea and the Norwegian Continental Shelf, but gives a clear idea of the CO2 storage potential in the North Sea.

Norway has stored CO2 in the North Sea since 1996, in the geological formations in Utsira. As we have mentioned in previous articles, existing oil and gas fields make excellent storage sites, because they are very likely impermeable, having stored oil and gas for millions of years already. This combined with the existing knowledge from storage in this area, makes the North Sea a very good candidate for storing CO2.

(See more about storage methods here)

In addition the saline aquifer areas outside the coast of Norway, with a projected capacity of 4.4 gigatonnes of CO2, the abandoned petroleum fields can store an estimated 1.1 gigatonnes of CO2. There are also possibilities to inject CO2 on other petroleum and gas fields for Enhanced Oil Recovery (EOR), although so far it has not proven to be efficient because there is not enough CO2 available.

The Norwegian Petroleum Directorate’s report only covers a small part of the North Sea, but indicates that there are vast possibilities for CO2 storage. Estimates for the Utsira formation are around 600 billion tonnes of CO2. The challenge is to use the available storage sites and to set up an appropriate legal and regulatory framework to enable CO2 storage in the area.

The challenge is to use the available storage sites and to set up an appropriate legal and regulatory framework to enable CO2 storage in the area

The North Sea Basin Task Force suggests defining a viable approach to long-term liability and stewardship, to define criteria for risk acceptance and site qualification, to establish monitoring and reporting requirements and to remove barriers to CCS in international conventions affecting the North Sea e.g., EU directives and emissions trading. This, in addition to financial incentives, are very similar to ZERO’s recent recommendations for CO2 storage.

ZERO has expressed that Norway should help elevating CCS as a solution by offering storage for CO2. Several countries in Europe, like Germany, have limited storage sites available, both for geological and political reasons. Norway could make an positive impact by offering to store CO2 for other countries.

ZERO suggests that the Norwegian State allows transportation of CO2 to cross borders and to accept the long-term responsibilities of storing CO2. This can be solved by bilateral agreements, which can be expanded when needed. ZERO assesses that the risk of long-term storage is low as long as the security and maintenance standards are high, and because Norway already has vast experience in storing CO2 in the Sleipner field. The storage must be open and available for third party actors to be shareholders or for members or the industry that do not have access to suitable storage sites.

While developing commercial storage, there should be a financial support system managed by the Norwegian government to promote storage within the EU. This would hopefully lead to more capture plants, a better infrastructure for transporting CO2, and in the long run create an environment for commercial CO2 storage.

While developing commercial storage, there should be a financial support system managed by the Norwegian government to promote storage within the EU.

Scottish Carbon Capture & Storage (SCCS) released a report in November 2013 where they offered additional recommendations for CO2 storage in the North Sea. The report confirms that the capacity in the North Sea is enough for large-scale storage, and SCCS suggests the surrounding nations must focus on delivering six pre-commercial operational storage sites to satisfy initial storage need until 2030.

In order to do this, there has to be bilateral or multilateral cooperation. SCCS suggests revitalizing and empowering the North Sea Basin Task Force to solve the issues surrounding the capture, transport and storage of CO2, and to provide the political drive to secure the necessary political framework.

The technological and geological capacity for storing CO2 in the North Sea exists, but the grand challenge is to get a working political and financial framework to support capture, transportation and storage.