There are already a large number of cables in the North Sea and a major issue is the decommissioning of cables that are end of life. Most countries state that there is an obligation to remove/decommission a cable after it is no longer in use. However, generally this is not enforced due to removal causing greater adverse effects than leaving them in situ. For cables left in situ, suitable monitoring measures are arranged but there is still with issue with some cables location not being marked properly on navigational shipping charts or cables being moved by anchors and bottom-fishing gear over time causing safety concerns. This is particular importance to fishing vessels for example who may snag their fishing nets on unmarked cables. MSP has a role to play in this challenge by ensuring that decommissioned but still in situ cables are appropriately marked for the safety of future marine users.
In terms of oil and gas pipelines, there will still be further development in Scotland, Norway and the Netherlands with decommissioning well underway but still the extension of new pipelines. However, the number of new pipelines is expected to stabilise after 2020.
The decommissioning of oil and gas pipelines has given rise to an opportunity which can be used to help combat climate change. The aim is to achieve a CO2 reduction of 80-95% in 2050. Capturing CO2 at the source and transporting it to storage locations deep underground, a technique called Carbon Capture and Storage (CCS), can achieve this. The Netherlands’s CO2 storage capacity in gas fields (current and former) is estimate to be 2,700 to 3,200 megatonnes (Mt) with 1,200 Mt being user the sea. However, there is still uncertainty as to what proportion of this capacity will be available for CO2 storage. In order to facilitate CCS, part of the pipeline infrastructure will have to be renewed. Existing oil and gas pipelines can only be used once the fields in question have been completely exhausted. At present, the Mining Act mandates the decommissioning of depleted fields (removal of platforms not in use). In a CCS vision under development, the Central Government is assessing whether policy changes would be desirable in this respect. Scotland is also currently investing in CCS. In the long run, the ambition is to arrive at a situation in which all energy is produced sustainable. The capture, use and storage of CO2 is a temporary solution during the transition to this situation. At the moment, this is an activity of national interest, however as it will be dependent on pipelines which cross borders, it may become of transnational interest.