A technical evaluation to analyse of potential repurposing of submarine pipelines for hydrogen and CCS using survival analysis

The UK oil and gas sector is mature and a combination of a dwindling resource base and a move towards decarbonisation has led to lower investments and an increasing decommissioning bill. Many existing offshore assets are in the vicinity of potential renewable energy developments or low-carbon facilities. We propose a technical evaluation process to understand whether pipelines might be repurposed to reduce the costs of lowcarbon energy investment and oil decommissioning.We identify survival analysis as an effective method to investigate the potential of pipelines repurposing based on historical failure records, as it deals with acceptable levels of data gaps and does not require associated field costs for detailed inspection. It provides a close estimate of the anticipated remaining life when compared to feasibility studies. We use survival analysis to examine several repurposing case studies for low-carbon investments. It also demonstrates that several pipeline systems have the potential to operate safely beyond their design life. Detailed records of failure will allow for further development of this methodology in the future.