HyTechnical – Literature, science review and subsequent revision technical standards for hydrogen pipelines
Status:
Complete
Project Reference Number:
NIA_SGN0165
START DATE:
END DATE:
Project summary
Funding Licensee(s):
Cadent
Northern Gas Networks
SGN
Wales & West Utilities
Funding mechanism:
Network Innovation Allowance
Research area:
GD - Future of gas
Technology:
Gas Distribution Networks
Expenditure:
£826,929
Summary
Learnings
Documents
move to decarbonisation in the UK has generated major interest in initiatives into the use of existing natural gas networks (pipelines and installations) for the transportation and distribution of hydrogen (H2) and natural gas/H2 mixtures. The SGN Future of the LTS Phase 1 project identified the potential to repurpose the LTS network. In February 2020 SGN held an industry workshop with attendees from the GDNs, NGGT, HSE, BEIS and industry experts. The aim of the workshop was to share and disseminate the knowledge from the first phase of the project, identify gaps and develop a roadmap for the future. The main outcome from the workshop was to develop a common framework of needs to allow the projects to be developed to complete the gaps. Following the workshop, we established IGEM LTS Futures group. This group will ensure the research undertaken underpins the national standards and supports hydrogen implementation. All the GDNs and NGGT are members of IGEM LTS Futures, which SGN chairs, and the work will be done collaboratively.
Following on from the Future of the LTS Phase 1 project, there is a requirement to undertake; material testing and analysis, desktop exercises to understand the impact hydrogen has on, (i) inspection, maintenance and repair (IMR) and (ii) repurposing pressure reduction installations (PRI) and closing gaps in the Quantified Risk Assessment (QRA). The desktop exercise to understand the impact hydrogen has on IMR, PRI and QRA will be done in parallel of writing the standards to provide input to the standards and further guidance to the GDNs and NGGT.
The development of approved industry standards to formalise requirements and secure safe best practise is needed to ensure consistency in repurposing existing natural gas networks, construction of new assets, and to ensure compliance with legislation. The GB gas industry are driving forward towards live consumer trials in the medium terms. As such it is imperative that the GB industry have a suit of supportive standards that deliver consistency and confidence in the engineering practise deployed for such trial activity and future expansion of hydrogen for heat. This is therefore a high priority. Current projects which will benefit from the availability of approved standards include, the SGN ‘Future of the LTS’ and H100 projects, the Cadent HyNet project which includes development in the WWU network, H21 and the National Grid HyNTS.
The standards which apply to the existing natural gas networks have been developed over many decades and are widely regarded having overseen significant improvements in asset delivery and management resulting in exemplary level of safety and reliability. These standards are published and managed by the Institution of Gas Engineers and Managers (IGEM). Following on from the Future of the LTS Phase 1 project, there is a requirement to undertake an urgent literature-based research for the development of new supplements/documents to these IGEM current natural gas standards which will enable the repurposing of the existing assets and the design and construction of new assets for H2 and Natural Gas/H2 mixtures. The research and the creation of new supplements/documents can be prepared, approved and published more quickly than developing new standards and can be incorporated into the existing standards when they are next reviewed. This NIA is directly focused on the future low carbon solutions for the gas industry which will support the government’s target of Net Zero by 2050 by creating technical standards which allow real engineering to be developed. This work is essential to provide, secure and sustainable long term customer benefits.
Objectives
The objective of this project is focused directly at the enabling of a low / zero carbon gas network of the future and enabling the safe transportation of hydrogen. It is essential the work is developed to provide, secure and sustainable long-term customer benefits.
It is critical that these standards are developed using the desktop exercises research undertaken and planned in the near term (eg. H21 Phase2) to support the change from natural gas to H2 and Natural Gas/H2 mixtures. Standards will need to be available for the application to the repurposing required for repurposing projects (e.g. SGN The Future of LTS).
They are also required to provide the requirements for the design, construction, testing, operation and maintenance of pipelines for the transmission and distribution of hydrogen and natural gas/hydrogen mixtures (Cadent HyNet & SGN H100). FEED studies for Cadent HyNet.
A hydrogen service risk ranking model has been developed for both pipelines and installation to identify those pipelines and installation which are less suited to hydrogen service.
Calculations of the BPDs for 100% hydrogen pipeline fires on an equivalent basis to those in IGEM/TD/1 for natural gas have been performed with a degree of confidence in the results and demonstrated that the equivalent BPDs for 100% hydrogen are approximately 10% smaller than for natural gas. However further work is recommended on overpressures. For parallel pipelines, the recommended minimum separation distances in IGEM/TD/1 for parallel natural gas pipelines should be cautious when applied to parallel hydrogen pipelines. Small number of experiments are required to study hydrogen vent releases, measuring noise levels and overpressures from delayed ignition of the release, in addition to thermal radiation. The information from the experiments will support analysis to determine whether the calculated “cautious” safe distances for thermal radiation hazards are sufficient or should be increased to take account of possible overpressure effects. Experimental measurements of noise levels could be used in conjunction with predictions of Flaresim and equations for noise in API 521 to modify the current approach in IGEM/SR/23 for hydrogen
The supplement to the standards IGEM/TD gives the additional requirements and qualifications for pipelines and installations for transporting hydrogen and hydrogen/natural gas blends (NG/H blends).
Lessons Learnt
HyTechnical has provided the first stepping stone to allow for industrial clusters and hydrogen trial projects to begin. The development of approved industry standards to formalise requirements and secure safe best practise will ensure consistency in repurposing existing natural gas networks, construction of new assets, and to ensure compliance with legislation. The GB gas industry are driving forward towards live consumer trials in the medium terms. As such it is imperative that the GB industry have a suit of supportive standards that deliver consistency and confidence in the engineering practise deployed for such trial activity and future expansion of hydrogen for heat. Current projects which will benefit from the availability of approved standards include, the SGN ‘Future of the LTS’ and H100 projects, the Cadent HyNet project which includes development in the WWU network, the NGN H21 programme and the National Grid HyNTS FutureGrid project.
Further work is required to close all known gaps, such as operational procedures and live working on hydrogen pipelines.