Net zero and the energy system transition
HyNTS Corrosion
The National Transmission System (NTS) pipelines employ a number of external corrosion barrier coatings primarily coal tar enamel and fusion bonded epoxy (FBE). Cathodic protection is deployed on the network to mitigate for coating failure. Additionally there are a range of pipeline steels that are used in both above ground buried pipework both stainless and carbon steels of various grades.
Following the previous NIA project: Research the Impact of Hydrogen on CP & Degradation of Coatings (NIA NGGT0191) the HSE have recommended follow-on testing to fully explore the impact of hydrogen permeation through steel pipelines on corrosion protection systems.
Additionally the impact of hydrogen on all credible pipeline corrosion mechanisms is to be considered to understand whether current assumptions with regards corrosion rates are valid for hydrogen pipelines.
Predictive Model for Flood Risk Management
This project will develop and evaluate a predictive flood monitoring system for Above Ground Installations (AGIs) and pipeline assets using real-time sensor data and 48-hour surface water forecasting. The system will be deployed at four locations identified through a nationwide flood risk survey. The trial will assess the system’s accuracy responsiveness and operational value across diverse environments. The project supports climate adaptation regulatory compliance and asset resilience by enabling early warning and proactive intervention. It aligns with RIIO-2 NIA objectives by reducing flood-related disruption enhancing safety and informing future investment decisions. The project will conclude with a technical report and recommendations for wider rollout under RIIO-3.
Hydrogen Environment Testing of Girth Welds Phase 2 - Constant Load Testing
Previous testing carried out under NIA has outstanding gaps that require further testing to close. Completing the additional testing will confirm actual fracture toughness values to be used and the corresponding J value from the crack growth resistance curve. The project outputs are required and will be used to progress design specification and procurement processes for hydrogen major projects. The results can also be applied for repurposing assessments.
Recompression Solutions for a Net Zero NTS
This project will provide National Gas Transmission (NGT) with a clear technical understanding and strategy for the deployment of recompression solutions for Net Zero gas networks including hydrogen blends 100% hydrogen and Carbon Dioxide transmission.
The NIA Safe Venting & Recompression of Hydrogen innovation project explored the possibility of repurposing natural gas recompression units for hydrogen blends and 100% hydrogen and investigated new solutions for hydrogen pipeline recompression as part of routine maintenance activities.
This project will take further NGT’s knowledge of hydrogen recompression for different scales and applications on the NTS to reduce venting and explore similar solutions for carbon dioxide pipelines.
WWU Intermediate Scale Hydrogen Storage Evaluation (HyWISE)
As the hydrogen economy grows the need for flexible decentralised intermediate-scale hydrogen storage is becoming increasingly evident. While large-scale underground hydrogen storage in salt caverns and depleted gas fields will play a crucial role in long-term energy security distributed intermediate scale storage solutions are essential to bridge the gap between production and end-use ensuring reliability efficiency and resilience in hydrogen supply chains during the scale-up of the hydrogen economy. Decentralised storage facilities allow for hydrogen hubs to emerge in urban and industrial areas reducing reliance on long-distance transport infrastructure and supporting regional hydrogen economies.
A key unknown is whether the land use and geology of Wales and South West England can support intermediate-scale underground hydrogen storage (UHS) technologies. This project aims to map and assess potential storage sites within the WWU region aligning with broader energy infrastructure plans—including hydrogen and gas pipelines electricity networks industrial demand and renewable energy integration. The project will use WWU’s geology and geography as a case study and demonstrate how UHS options can support wider energy infrastructure in the region and beyond as well as future project plans. For this reason the outputs are expected to be of value to all networks.
To evaluate the feasibility of these storage solutions the University of Edinburgh will analyse rock property and strength data from publicly accessible British Geological Survey (BGS) datasets developing new insights into the engineering suitability of the region’s subsurface for hydrogen storage.
Hydrogen Refuelling from the Network
Wales & West Utilities (WWU) is undertaking a project to develop a thorough understanding of the technical and economic requirements for integrating hydrogen refuelling stations (HRS) into the existing gas network. The main aim is to enable the supply of ‘on-spec’ hydrogen for fuel cell electric vehicles (FCEVs) and hydrogen internal combustion engines (HICEs) from the heat-grade hydrogen currently delivered by the network. This involves analysing the types of contaminants present in grid hydrogen pinpointing the purification technologies needed and assessing the infrastructure requirements for compression chilling and storage to deliver hydrogen at the target pressures of 350 and 700 bar.
Hydrogen Fuel Cell Operating Hub for Repex/Large-Scale Projects
To maintain their above ground and underground pipework assets all Gas Distribution Networks (GDN) operate substantial fleets of commercial vehicles (primarily vans but also HGVs) together with mobile plant and powered equipment. Presently there is a complete reliance on hydrocarbon fuels primarily diesel and petrol. Both fuel types are usually sourced via the public retail forecourt network. Similar issues exist for other utility providers that operate underground and overground infrastructure.
Wales & West Utilities is undertaking a major programme of change to support decarbonisation and deliver a hydrogen-ready Net Zero gas network. Our distribution network iron mains replacement programme (Repex) requires significant excavation and pipe replacement activity laying long-life hydrogen-ready polyethylene pipe by a variety of means.
The project endeavours to identify a suite of suitable zero-emission mobile plant assets tools and equipment for carrying out Repex work that WWU could hire or purchase for operational trials and to identify opportunities for changing equipment items to simplify recharging/refuelling requirements in the future.
The objectives of this project are:
- To analyse current energy demands sound pressure and vibration levels associated with existing ICE powered mobile plant assets ICE-powered tools and equipment and electrical equipment used for carrying out planned iron mains replacement work on the gas distribution network.
- To estimate the future electrical energy demands (and sound pressure and vibration levels) placed by future zero-emission powered tools and equipment on a zero-emission site-based power generation facility.
- To identify opportunities for changing equipment items to simplify recharging/refuelling requirements in future.
- To identify a suite of suitable zero-emission mobile plant assets tools and equipment that WWU could hire (or purchase) and utilise for operational trials short and longer term. This will include the energy source and the means of recharging and/or refuelling on site and/or at regional depot locations.
Economics of Biomethane
The consultant will deliver a report with supporting data to demonstrate that the economics stack up for biomethane while also supporting the UK’s net zero ambitions and contributing to our energy security.
Calorific Gas Sensor
The UK and Irish gas networks are undergoing a major transition to support the integration of green gases including biomethane and hydrogen. A significant challenge is the inability of the current gas billing infrastructure based on flow-weighted average calorific value (CV) measurements taken at National Transmission System (NTS) offtakes to accurately reflect the gas composition received by consumers—particularly with the increasing number of decentralised injection points. This discrepancy presents a technical and regulatory hurdle to achieving fair and transparent billing.
This programme is leveraging 3 suppliers to develop a range of novel calorific value sensors that will enable calorific value to be accurately measured at different points on the network without the need for venting.
The programme comprises of 3 individual projects which will develop each suppliers’ technology up to a sufficiently high TRL where the sensors are ready to be trialled in the field. Each supplier will be delivering their own scope of work but will be expected to share a reasonable amount of information with each other in order to ensure maximum value is obtained from this programme. The innovators will not be expected to disclose any information that could provide them with a competitive advantage over the other solutions
MASiP Phase 3 (Qualification Testing & Integrated System Development)
The MASiP Phase 3 project aims to develop test and qualify a new pipeline system (MASiP) as a safe and cost-effective alternative to traditional steel pipelines for pipelines operating above 7 bar capable of transporting natural gas biogas and up to 100% hydrogen. Building on Phases 1 and 2 this phase focuses on the technical assessment of tight radius bends tees and damage repair as well as the integration of live monitoring systems in a prototype operational environment. Comprehensive validation will include connectors coatings repair systems hot-tapping solutions ground movement tolerance durability and design life testing. All testing will be carried out in accordance with IGEM API and ASME standards supported by statistical and independently witnessed trials to generate robust qualification data for industry adoption. The key deliverable is a validated deployable hydrogen-ready pipeline system that is safe compliant and cost-effective offering potential cost savings of up to 50% compared with steel. The project outcomes will support the UK’s RIIO-GD2 strategy and 2050 net-zero targets by enabling hydrogen-ready infrastructure improving monitoring installation efficiency and long-term reliability while also providing the evidence base required for regulatory policy and industry acceptance of alternative pipeline materials.
Human Behaviours and automation
This project will produce valuable insights into understanding the relationship between human behaviours and the utilisation of safety devices with automated functionality. This follows the work done on hydrogen risk mitigations which included technology such as hydrogen detectors with automated functionality to remotely notify the emergency call centre to dispatch an engineer to the detected leak. In their review of this work HSE have asked if the assumption that consumers will continue to act the same knowing the device will be doing some automated will change the validity of the modelling assumptions. This project will address that query and build on our own understanding of consumer insights; something which could add a depth of value to other projects exploring automated safety systems.
Variable Blends Operational
Blending hydrogen and natural gas into the NTS has some clear benefits for supporting the transition of the energy industry in the UK to net zero in 2050 and is seen as an important intermediary step towards that goal.
It is expected that initially a low percentage hydrogen blend will be accepted onto the National Transmission System with this potentially increasing up to 20% hydrogen blends being accepted. However whether a hydrogen producer has to put in a specific blend percentage has not been determined and is unlikely. Therefore NGT need to develop the system to be able to effectively manage variable blends in addition to 2% 5% and 20% hydrogen blends.
This project will look into 4 key areas that might be directly impacted by hydrogen blend variability and require impact and risk assessments followed by investigations resulting in solution mapping and mitigation strategies being proposed. The key topics include establishing permissible limits for variability investigating how to manage interconnection from NTS to other countries understanding the effects of variability on stratification potential in the network and investigating the effects of variability on combustor/compression modelling.
HyNTS Operational Methodologies - Valve Performance Assessments
This project aims to assess and enhance the hydrogen readiness of ball valves within the (NTS) by conducting maintenance strategy evaluation with material performance analysis. It involves reviewing current valve operations diagnostics and OEM maintenance guidance alongside a literature review of commonly used valve materials to understand their behaviour under hydrogen exposure. The project valve performance testing and finite element analysis of existing valve designs to evaluate structural integrity. Findings from these activities will provide actionable recommendations for updating NGT’s valves maintenance strategies diagnostic tools and design standards to support safe and efficient hydrogen service deployment
HyNTS Operational: Qualification of Pressure Vessels
The National Transmission System (NTS) uses dry scrubbers filters and strainers to remove contaminants in the gas stream. Introducing hydrogen raises new challenges due to its distinct properties which could affect the performance and efficiency of these existing cleaning assets. We completed a project that investigated the compatibility of these assets with hydrogen and hydrogen blends to ensure gas quality without compromising the safety or efficiency. An outcome was to get a deeper understanding of the fracture and fatigue behaviours of these equipment to better understand whether hydrogen will impact the material properties. This assessment will undertake a targeted CTR analysis to inform a future potential physical test programme.
Gas Inhibitors for Hydrogen Pipelines - Phase 3
The Phase 3 project on gas inhibitors for hydrogen pipelines aims to translate lab-scale findings into practical applications for the UK’s National Transmission System. It focuses on validating the effectiveness of oxygen and alternative inhibitors in mitigating hydrogen embrittlement addressing unresolved safety and integrity concerns from previous phases and designing a plan for safe integration into existing infrastructure. The project includes physical demonstration planning and network design to assess technology implementation.
Girth Weld Inspection of Steel Pipelines for Repurposing to Hydrogen Service
Repurposing of natural gas pipelines made of carbon steel for use with hydrogen blends requires a fitness-for-service analysis as part of the hydrogen use safety case. Girth welds of an unknown quality exist in the Local Transmission System (LTS). In hydrogen service these welds would have a greater susceptibility to fracture failure due to material embrittlement caused by interaction of steel material with hydrogen.
Current in-line inspection methods do not routinely inspect girth welds for defects. This project aims to test the available technology for its capability to detect defects and cracks in girth welds. This will provide valuable data for engineering critical assessments required to repurpose natural gas pipelines. It will also inform about the state of art inspection techniques and whether they can be used as a tool for repurposing pipelines.
Hydrogen Combustion Engine Feasibility Study
This project will see Cenex deliver a feasibility study on hydrogen internal combustion engines (H2ICE) as an alternative to diesel and Fuel Cell Electric Vehicle (FCEV) within WWU’s operational fleet. This project comprises three distinct work packages (WPs) each feeding into a holistic assessment of H2ICE applicability across WWU’s vehicle assets. Cenex will apply its expertise in fleet decarbonisation alternative fuel technologies legislative policy analysis and techno-economic modelling to meet WWU’s scope requirements. All outputs will be suitable for internal strategic review and for sharing externally with partners and stakeholders.
Blending Management Approach – Phase 2
The conversion of the National Transmission System into a hydrogen transmission network has been widely discussed and it is recognised that blending of hydrogen and natural gas in the network is an important intermediary step towards that goal. It is therefore important to understand how the NTS will operate with a mix of natural gas and variable blends up to 20% hydrogen.
The Blending Management Approach (BMA) Phase 2 project will explore the operational safety and strategic implications of introducing low-level hydrogen blends into the National Transmission System (NTS) with a particular focus on storage interactions emergency response scenarios and long-term network management strategies. This phase aims to deepen understanding of how hydrogen blends interact with existing infrastructure and protocols.
Scaling Hydrogen with Nuclear Energy (SHyNE)
Significant efforts are required to support the transition of our energy systems moving away from carbon-intensive fuels such as coal diesel petrol and gas towards cleaner sources of power generation such as wind solar nuclear and hydrogen. There is a potential for hydrogen to play a hugely significant role in our energy system the extent of which will be driven by a range of factors including the ability to transport it to where it is needed. There have been recent positive decisions for hydrogen’s potential uses in blending transportation domestic heating and industry. To produce sufficient hydrogen to meet this potential need it will be important to increase and diversify hydrogen production methods.
As nuclear is a reliable and consistent source of clean energy that is unaffected by external factors such as the weather Northern Gas Networks and Wales and West Utilities would like to investigate the possible use of nuclear power as a method of delivering the future increased demand in hydrogen production. This project will explore the opportunity for hydrogen production from nuclear to support a net zero transition across the gas network.
Benefits of nuclear-enabled hydrogen (NEH) in the context of gas distribution networks (GDNs) will be explored building on the established benefits of nuclear energy production.
The overall project outcome is that NGN WWU and other stakeholders are sufficiently informed to determine whether further investment and integration of nuclear-enabled hydrogen to transition plans are justified and how a potential first project could take its next step to deployment through securing technology licences sites off takers and financing.
Risk of Microbial Corrosion due to Hydrogen Transportation
National gas pipeline systems rely heavily on protective coatings and cathodic protection to prevent corrosion and ensure long-term integrity. Coatings act as the primary barrier against environmental exposure while cathodic protection—typically using sacrificial anodes or impressed current systems—supplements this by mitigating electrochemical reactions that cause metal degradation. The introduction of hydrogen into these pipelines as part of decarbonization efforts presents new challenges. Hydrogen can permeate coatings and accelerate corrosion processes especially in the presence of certain microbes. Microbiologically induced corrosion (MIC) driven by bacteria such as sulphate-reducing bacteria (SRB) can be exacerbated by hydrogen which some microbes use as an energy source. This interaction may compromise both the coating and cathodic protection systems necessitating advanced materials and monitoring strategies to maintain pipeline safety and performance in a hydrogen-integrated future.