Vattenfall explores CO₂ storage sites in Brandenburg

Together with Verbundnetz Gas and Schlumberger, Vattenfall has initiated exploration of two different possible storage sites in the German federal state of Brandenburg. The aim is to investigate the potential of these aquifers to store the carbon dioxide, CO₂, from Vattenfall’s envisaged CCS demonstration project in Jänschwalde.

One of the focal points of Vattenfall’s CCS activities is to establish the CCS demonstration plant in Jänschwalde and usable storage capacity must be identified and developed for this purpose. The sedimentary rocks of the North German Basin offer excellent geological conditions, as there is a high incidence of deep underground sandstone strata. The deep-lying sandstone horizons consist of porous rocks, saline aquifers, that today contain brine, that is water with a high mineral content making it unfit for human consumption. In most cases they are encompassed by solid layers of salt or clay, which are impermeable to liquids and gas. This makes them very good candidates for CO₂ storage, something that will now be closely investigated.

The sedimentary rocks in the North German Basin were screened between 2004 and 2008. As a result of the screening process the structures Birkholz-Beeskow and Neutrebbin, both in the east of the state of Brandenburg, were chosen as locations for further exploration. Both structures are promising in terms of capacity, injectivity and storage integrity. The storage capacity of the two structures is estimated to be more than 100 million tonnes.

The exploration programme to screen the structures best suited for storage will begin in 2009 and end in 2011 and will be implemented in three phases: seismic studies, exploration drilling and simulation of the flow properties within the sediment strata in a test programme. The first phase will commence with seismic studies of the Birkholz and the Neutrebbin structures. For both structures a total area of more than 300 km2 will be evaluated using vibration seismology.

If the exploration is successful, the storage sites will be developed.

The connection system between the injection drill hole and the transport pipeline will be implemented in the period 2011 to 2015. This will be followed by transport via a gas pipeline from the demonstration plant in Jänschwalde to the storage site. The pipeline, up to 150 km in length, will be built with a distribution system but no pressure boosting system.