North Sea CO2 storage should be confined to unavoidable emissions due to limited capacity, environmental risks – report

Limited capacity and environmental risks mean that carbon storage in the German North Sea should only be used for residual emissions that remain unavoidable, said researchers from the GEOSTOR consortium of institutes. A number of major challenges must be overcome before CO2 can be injected under the seabed. These include creating regulations, finding measures to prevent potential leakage, and dealing with the noise generated during activities such as site exploration and monitoring, said researcher Klaus Wallmann from GEOMAR Helmholtz Centre for Ocean Research Kiel.

“Furthermore, solutions must be found for foreseeable conflicts of use - such as with offshore wind farms - and these must be appropriately considered within the framework of marine spatial planning,“ he added. The research report assessed storage capacity in the region, leakage potential and other risks, technologies and costs, the regulatory framework, and the competition with other uses of the area.

In the North Sea, CO2 could be transported by pipeline or ship and injected into porous sandstone layers at a depth of over 800 metres below the seabed. Storing CO2 in parts of the North Sea would cost 13-55 euros per tonne. However, this excluded the capture and transport on land, which can be “very complex and expensive”, said the report.

Years of protests against industry plans to use carbon capture and storage (CCS) as a lifeline for coal power have made the technology a no-go issue for many politicians in Germany, Europe and beyond. But countries' goals of climate neutrality around the mid-century reopened the debate on the issue of combatting CO2 emissions that are difficult to avoid, for example in cement production. Germany’s prospective next coalition government has decided to adopt a legislative package to allow CCS, especially for hard to avoid industry emissions, immediately at the start of new legislative period. The outgoing government had failed to adopt the legislation, which would allow carbon storage under the North Sea.