In order to meet current future fuels and energy transition targets that have already been set as part of national and international strategies, repurposing of existing infrastructure plays a key role. This introduces new challenges for pipeline owners and operators, including the requirement to safely repurpose aging pipelines for a new service (e.g., hydrogen or CO₂) while maintaining integrity, now and in future operations.

The first part of the paper will discuss the integrity implications of the energy transition for existing pipelines. It will outline an industry best practice from a pipeline integrity standpoint and show how this approach could support pipeline operators in de-risking the conversion process. The applicability of existing codes to (converted) pipelines will be taken in consideration. The paper will emphasize an integrity-led, fitness-for-service approach to repurposing, which can offer a pragmatic solution to repurposing decades old infrastructure not originally designed or constructed with future fuels in mind. In addition, a stage gate approach to integrity management will be outlined. , including use cases showing how front runners are using this approach to run a cost-efficient conversion selection process.

The second part of the paper will address challenges operators and ILI service providers will face when looking at potential future pipeline operating conditions and resulting survey conditions during inspection. Providing an H₂-ready tool fleet, operational and mechanical challenges as well as safety-related aspects concerning inspection and integrity maintenance for pipelines carrying H₂ are being addressed. Providing relevant case studies on the integrity management approach where ILI was performed in hydrogen, the paper will discuss the impact of operational characteristics of an H₂ pipeline with respect to various pressures, flow rates, pressure swings, etc.