At the end of 2006, Gassnova, Gassco, the Norwegian Petroleum Directorate and NVE (the Norwegian Water Resources and Energy Directorate) were assigned the task of studying a basis for making a decision on transport and storage solutions for both Mongstad and Kårstø, viewed in an overall context. The study recommended further investigation of two storage locations, the Johansen formation and the Utsira formation.
In the spring of 2009, the Government decided to halt the Kårstø project due to operational factors at the power plant. Work in progress on the relevant storage location in the Utsira formation was completed.
As regards the full-scale project at Mongstad, the Johansen formation was regarded as being the most suitable storage site due to safety, distance and capacity. At the present time, this is one of the most thoroughly studied stores on the Norwegian shelf. Seismic surveys were carried out on the Johansen formation in the summer of 2010, and the estimate is that Johansen can store at least 160 million tonnes of CO2.
There will always be uncertainties related to the properties of the storage formation in a research and study phase. This uncertainty cannot be significantly reduced until data has been obtained, e.g. from a drilling operation. In order to be assured that storage would be available for the capture facility at Mongstad when it was ready to start up, a decision was made to study alternative storage locations, with the subsequent decision to pursue Troll Kystnær. In the summer of 2011, seismic surveys were carried out on Troll Kystnær, and a report was completed in the fall of 2012.
Gassnova has worked in parallel to examine models for how a transport and storage solution for Mongstad full-scale could be organised. Involving competent industrial players was one of the important principles here, along with establishing an expedient division of roles between the State and industrial players.
In technical terms, storing CO2 under the seabed on the Norwegian shelf is a perfectly manageable option. For example, Statoil has been storing CO2 from the Sleipner field in the Utsira formation since 1996. Data and models from Gassnova's transport and storage projects have been made available to research and development projects in Norway and internationally, and have thus contributed to further development of technology.
So far, however, it has proved challenging to put good business models into place that provide relevant storage operators with incentives to get involved in CO2 storage. Without clear framework conditions and regulations in place, potential operators have regarded the uncertainty as being too great at the present time. Work is under way to establish clearer framework conditions, both on the national and international scenes. Gassnova plays an important role in advising the Ministry of Petroleum and Energy in this work.
Ship_transport of CO2 (Tel-Tek,_2014) (.pdf)