The proposed project addresses the call topic area of ‘low-carbon energy carrier roles in accelerating decarbonisaton pathways’ by characterising the condition of legacy gas (methane) pipeline steels after service exposure. Existing hydrogen embrittlement relationships do not properly consider the effect of steel pedigree on degradation. This research will use the results of detailed characterisation to fully document steel microstructure and rigorously track hydrogen interaction with specific features. The results will be directly relevant to assessing the suitability of the current network for hydrogen gas transport. Moreover, the learnings will inform the design and manufacture of future systems. Support involving the supply of suitable legacy specimens has been obtained from National Grid and EPRI will provide review and input on methods used and aid dissemination of findings.
Benefits
This project will increase understanding of how defects react when regularly fatigued in a hydrogen environment. This is a critical point of understanding for the operation of the NTS and will inform defect tolerance specifications and operational practices.
Learnings
Outcomes
No key outcomes have been generated to date. It is expected that the main project findings will be generated during and following the experimental test programme phase of the project which has just started.
The project value tracking is listed below:
· Maturity
o TRL 2-3. PhD project looking at novel fatigue approaches for hydrogen enhanced fatigue of pipeline materials.
· Opportunity
o 100% of single asset class. All pipeline materials.
· Deployment Costs
o £ 0.00. No direct deployment costs expected.
· Innovation Cost
o £ 37,000 – National Gas contribution
· Financial Saving
o £ 0.00. Results could lead to eventual policy updates which might result in additional or reduced operational costs.
· Safety
o 0% improvement. Results will be used to ensure continued safety of pipeline operating in hydrogen potentially via policy updates.
· Environmental
o 0 tonnes CO2e saving. Results will support continued safe operation of pipelines in hydrogen, thereby reducing gas escape and optimising remediation activities (e.g. excavations) with associated environmental benefits.
· Compliance
o Support compliance. Results could lead to eventual policy updates which might be required for operation of pipelines in hydrogen.
· Skills & Competencies
o Individuals. Work will augment knowledge of individuals involved in project.
· Future Proof
o Supports business strategy. Results will support operation of future hydrogen National Transmission System.
The forecasted benefits are data and a deeper understanding of the fatigue behaviour of pipeline materials in hydrogen which will feed into future design and integrity management strategies for hydrogen transmission, with the intention of maximising value to customer by reducing conservatism whilst not compromising on safety. These forecasted benefits will be delivered throughout the project up to its completion in 2026.
Lessons Learnt
Some delays were experienced related to procurement of pipe material and subsequent machining of the test specimens. In future project scoping, agreement should be sought between project partners as to their responsibilities and availability of necessary resources in accordance with project plan.
