Future Energy Networks

This project constitutes a research study assessing the future demand for hydrogen across SGN regions and the role SGN infrastructure could play in facilitating access to hydrogen.

As the UK transitions to a low-carbon energy future, gas networks must consider how strategic utilisation of existing assets can be realised. Using SGN’s extensive gas network to carry hydrogen instead of natural gas would be a major step towards decarbonisation. This repurposing necessitates an understanding of both the technical feasibility of repurposing pipelines to carry hydrogen, and future hydrogen demand requirements.

This project will help to inform UK Gas Distribution Network Operators (GDNOs) and wider industry on the impact of the potential for air ingress into gas-conveying pipework in MOBs. The mechanisms for air ingress into gas-conveying pipework have been shown to be gas agnostic, though this project will focus on impacts specific to future hydrogen distribution to MOBs.

This project will consider what role the below ground gas network (new or repurposed) could play in transporting energy over long distances, instead of electricity transmission and distribution upgrades. The project will help WWU understand how the use of the current or future gas system would compare to electricity infrastructure for long distance transmission, and what factors could influence cross system decision making. The project will also create a comparison tool that allows users to compare case studies.

The project aims to use a vehicle-mounted thermal camera and Artificial Intelligence (AI) to detect heat loss from homes on a city-wide scale. The data will be used to assess the condition of a property regarding its ability to retain heat and provide tailored recommendations addressing insulation problems. This critical first step allows for better targeting of necessary retrofits and offers a scientifically measured alternative or complementary approach to traditional EPC.

The Asset Cortex project is a Generative AI initiative by National Gas Transmission (NGT) aimed at transforming its legacy 4-level asset hierarchy into a deeper, ISO 14224-compliant structure. This Proof of Concept (PoC) will explore the feasibility of using AI to infer component-level details from system-level data such as pressure and age, enabling automated hierarchy generation. The project supports RIIO-GT3 objectives, including predictive maintenance, digital twin creation, and improved asset lifecycle visibility. It will also enhance integration with systems like SAP and Copperleaf, and streamline field force operations. Key phases include requirements capture, data mapping, AI model development, benchmarking against manually collected data, and final reporting. Grasby Bottom and Hatton Multi Junction sites will serve as testbeds. The project is expected to reduce manual effort, improve scalability, and lay the foundation for broader digital transformation. It will also inform IT infrastructure needs and data governance strategies. While the current phase focuses on feasibility, successful validation could lead to full-scale deployment, supporting NGT’s strategic goals around automation, cost efficiency, and sustainability. Asset Cortex is positioned as a foundational enabler for future infrastructure planning and operational excellence across the gas network.

Augmented Reality (AR) technology will be used at Futures Close to convey and inform various audiences including vulnerable consumers about various property archetypes, their construction, heat loss, and the type of retrofit solutions (heating systems, controls, fabric improvements) available to improve the level of domestic energy efficiency. AR will be used to inform, educate and engage audiences on-site at Futures Close as well as off-site at conferences and meetings avoiding the need to facilitate multiple visits on site. Live data feeds will also be visualised, illustrating room-by-room temperature, humidity as well as other metrics providing an engaging, interactive and informative asset for Futures Close.

Linepack flexibility is key for Gas Transmission to provide system resilience by management of swings within operational limits. In a hydrogen world, we know our energy content per km of linepack will decrease by up to 76%. Therefore, embedded resilience systems in the form of lined rock shafts are being investigated to supplement loss in linepack capability. We envision systems if implemented for hydrogen transmission to act similar to how now decommissioned natural gas holders were utilised for operational flexibility, pressure regulation, supply/demand mismatch management, load balancing, emergency backup and production buffering.

This project constitutes a GB-wide analysis of biomethane feedstock arisings including location, determination of quality and composition of each feedstock type and biomethane production potential. Arisings will be quantified to county-level. Mapping software will be used to determine feedstock hotspots and alignment with the grid will be considered. The results of these analyses will be combined to consider how and where sustainable biomethane growth can best be achieved.

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

As the UK transitions to a low-carbon energy future, gas networks must consider how strategic utilisation of existing assets can be realised. GDNs must also consider adjacent markets such as CCUS and its role in the supply chain now and in the future. The project will take a pragmatic approach to provide SGN with an assessment of the role of the gas network in the growing UK CCUS market

This project seeks to improve the accuracy of CV measurement in gas networks which distribute blended gas streams. Element Digital Engineering will address this by first studying the physics of gas blending in the gas network using Computational Fluid Dynamics (CFD). A wide range of simulations will enable the effects of different designs and mixing technologies to be understood in relation to the various gases under consideration. The predictions of these CFD studies will be validated through the design and development of a rig to simulate blending in the network. The overall results of these studies will be used to develop a tool that can be deployed within the gas networks to facilitate the accurate prediction of co-mingling, and subsequent CV measurement points supporting the design of blending systems.

National Gas Transmission (NGT) are committed to reducing emissions from the operation of the National Transmission System (NTS) and eliminating emissions by 2050. The transition to hydrogen provides an opportunity to reduce carbon and utilise the network for hydrogen refuelling for transport. The HyNTS Deblending for Hydrogen Transport project has involved the development of a UK-wide rollout strategy from ERM that lays out demand, clustering and potential locations for deblending supplied refuelling for transportation mapped against the NTS.

The project will aims to obtain further information on NRMM, maritime, cars, LGVs and mobile power to fully understand the hydrogen demand. It will also review the existing rollout strategy to ensure it is accurate and full captures the current hydrogen market given the changes in this landscape

This project constitutes a research study investigating the opportunities for gas network infrastructure to support storage and balancing in a decentralised UK energy system. The research will consider how a decentralised system might look in the UK from now until 2030, and onto 2050. An evaluation will be made of how other countries are approaching decentralisation, identifying examples the UK could draw on. Consideration will be given to how grid balancing will be achieved across various scenarios of peak demand and particular geographic locations in the UK and what challenges and opportunities this presents to gas networks.

Wales & West Utilities is undertaking a major programme of change to support decarbonisation and deliver a Net Zero gas network. Decarbonisation of the vehicle fleet is an integral component of that programme.

WWU operates a fleet of nearly 1,400 commercial vehicles, the majority of these being vans up to 3.5 tonnes GVW. Our fleet – mostly diesel-fuelled - plays a crucial role in providing a safe and efficient service. In addition to our vehicle fleet, WWU operates ~ 900 items of mobile plant, including mini diggers and a wide range of trailers, many of which are specialised.

WWU vans carry a wide range of power-operated tools and equipment, some of this currently being powered by hydrocarbon fuels, some by electricity and some by compressed air. Approximately a third of our van fleet (~400 units) is equipped with ‘full on-board power’ – a compressor and generator, mounted under the van floor and mechanically driven by the diesel engine and operating as a source of on-site power.

This group of vehicles primarily supports below-ground network repair and replacement activity: it is a significant energy consumer, so to help us understand how we can make an operationally cost-effective transition to zero emissions, it is the on-site energy requirements of the tools and equipment powered by this group that Cenex will evaluate for this project. This evaluation will provide information which can take account of (and feed in to) a range of different scenarios for the fleet in the future, such as changes to the number and type of vans allocated to particular teams and projects.

As the Gas Transmission network responds to a changing energy system, from drivers including the transition to net zero and to changes in supply and demand, we are required to decommission our large site based assets in certain locations. Decommissioning is a multifaceted endeavour that goes beyond the conclusion of an asset’s lifespan and encompasses a complex deconstruction process. This project will implement an innovative AI tool to help National Gas manage decommissioning to drive benefits such as increasing the accuracy of cost estimation, ways to reduce carbon emissions, identify re-use potential and lower the overall time taken to decommission.

UK’s Net Zero Emissions Target and the Role of Hydrogen: The UK has committed to a legally binding net zero emissions target by 2050. Achieving this target necessitates the integration of hydrogen, particularly in hard-to-decarbonize industrial applications and peaking power generation. The recent publication of the Climate Change Committee’s Seventh Carbon Budget highlights hydrogen’s significant role within the electricity supply sector. Hydrogen is identified as a crucial source of long-term storable energy that can be dispatched as needed and as a feedstock for synthetic fuels. For hydrogen to fully contribute to a future hydrogen system, its production, storage, and transportation must be considered collectively.

East Coast Hydrogen (ECH) Project: In recent years, Cadent, in partnership with National Gas and Northern Gas Networks (NGN), has developed the East Coast Hydrogen (ECH) Project. The ECH project aims to decarbonize primarily industry and power sectors. As part of this initiative, Cadent has developed the East Midlands Hydrogen Pipeline (EMHP), which aims to connect hydrogen production at Uniper’s Ratcliffe on Soar site to major industrial and power off-takers in the East Midlands. The project seeks to transport hydrogen to major population centres, including Nottingham, Leicester, Melton Mowbray, Derby, and Burton upon Trent. During the development of the EMHP, it became evident that hydrogen storage plays a critical role in establishing a resilient and efficient hydrogen system. Consequently, a consortium was formed to explore the feasibility of storage, leading to the East Midlands Storage Project (EMSTOR).

Discovery Phase of EMSTOR: During the Discovery Phase, EMSTOR evaluated various technologies for large-scale hydrogen storage in the East Midlands. The technologies considered included lined rock caverns, lined rock shafts, silos, and geological storage options such as aquifers and disused hydrocarbon fields. After comparing these technologies against several technical parameters, including Technology Readiness Level (TRL), cost, size, and location relative to pipelines, it was determined that hydrogen storage in geological fields, particularly disused hydrocarbon fields, is the most viable option. Therefore, disused hydrocarbon fields in geological formations were selected for further consideration in the Alpha Phase.

Alpha Phase Consortium: To execute the Alpha Phase, a consortium led by Cadent and including Star Energy Ltd, Centrica Energy Storage, National Grid, British Geological Society, University of Edinburgh, and Uniper was established. This consortium will focus on advancing the feasibility and implementation of hydrogen storage in disused hydrocarbon fields.

Wales & West Utilities is undertaking a major programme of change to support decarbonisation and deliver a Net Zero gas network. The primary objective of this project is to investigate the effects of water ingress within a 100% hydrogen network and a blended hydrogen/natural gas network. The goal is to determine whether the introduction of hydrogen into the gas network could cause any additional impacts when water ingress occurs, and to compare these effects to those observed in the current natural gas network.

The UK Government recognised that domestic biomethane production can play a significant role in decarbonising energy supplies. However, biomethane production plants face technical and operational challenges. Currently the content of biomethane within biogas produced from the anaerobic digestion (AD) process is often only around 50%. This partial conversion results in lower yields for AD operators and an increase in costly gas scrubbing requirements. The increased presence of impurity gases also increases requirement for propanation to increase the calorific value, high in both cost and carbon footprint.

This project seeks to address these challenges through the injection of green hydrogen into the AD process in specific quantities and at specific times to achieve greater conversion of carbon dioxide to biomethane within the acetogenesis stage of the AD process, thereby increasing the yield whilst reducing the need for gas scrubbing and propanation.

This project will help to inform UK Gas Distribution Network Operators (GDNOs) and wider industry on the long-term suitability of existing Excess Flow Valve (EFV) designs in a future where hydrogen is being distributed in network pipelines. A risk to normal EFV functionality exists in the event that an ignition occurs within the downstream gas installation pipework and this project will help to understand the effectiveness of existing EFV designs to manage this risk, identifying any necessary modifications to existing EFV designs where appropriate.

This innovation project proposal is centred on trialling the development of a predictive model to identify customers in vulnerable situations whose heat comes from Cadent delivered gas that are missing out on the protections that the Priority Service Register (PSR) brings because they are “hidden” behind a non-domestic supply contract. The aim of the predictive model would be to aid Cadent to find these customers so that it can be ensured that they receive the support that they need in the event of an interruption to supply.

Gas networks supply embedded power stations that support the electricity network. These embedded generators can fire up without any warning to GDNs and is causing significant challenges to gas networks.

GDNs are required to submit hourly gas demand nominations to National Gas for each offtake point within specified time deadlines.

Embedded generators are small. They are not included in the UNC’s requirements to notify their GDN of intended offtake activity due to their size being below the threshold for NExAs (network exit agreements). Despite this, GDNs must include the demand from these embedded generators in their nominations to ensure there is sufficient gas within their network. This causes numerous challenges for SGN and other GDNs.

GDNs’ current forecasting process does not specifically forecast embedded gas generation, and current models do not take inputs from the electricity market. Embedded generators act in a variety of electricity markets, yet GDNs don’t have visibility of this demand.

It is anticipated that additional embedded generators will connect in the coming months/years as the demand for electricity increases.The challenge of not having knowledge of embedded generator’s demand and its potential to contribute to a storage shortage has been acknowledged by both EGRIT (Electricity and Gas Resilience Task Group) and NESO (National Energy System Operator). The benefits of creating a notification platform supported by a ML engine are various. Namely to develop an ML-enabled forecasting tool to predict gas demand from embedded generators with increased accuracy as delivery time approaches. In addition to create a notification platform to improve real-time visibility of embedded generator activities within the electricity and gas networks.

This NIA project aims to progress the FEmGE forecasting tool from TRL 1 to TRL 7, delivering a fully functional MVP. NGN will be funding this project to the value of £92,333 and SGN to £184,666 of the total of £276,999.

The project will develop an integrated hierarchical network modelling framework for simulating the operation of future GB energy system scenarios with highly interconnected gas and power networks. The realistic modelling of power-to-gas and storage operators’ behaviour will be emphasised. The integrated models will be demonstrated on a simulation platform as real-time digital twins for future system scenarios.

Considerable novelty will lie in the combination of modelling scale and granularity; representation of many autonomous decentralised agents making sub-optimal decisions; and the optimal resolution of dilemmas arising from the finite energy budgets constraining primarily weather-driven low to zero carbon scenarios.

To reach our national net zero targets by 2050, we need to decarbonise approximately 25 million homes in England. Domestic heating accounts for approximately 14% of the UKs entire emissions and significant investment is required to improve the energy efficiency of our housing stock. In addition, there are major challenges associated with domestic decarbonisation:

• England has the most diverse housing stock in the UK. with 35% built before the end of WWII.
• Sixty-four percent are owner-occupied, and these homeowners need to have a good, cost effective and efficient experience of home and heating upgrade as we move towards zero carbon homes.
• Implementing heating upgrades to this ageing housing stock requires a ‘whole house’ approach therefore, consideration must be given to the building fabric and heating system.

Retrofitting existing homes with electric heating systems or deployment of green hydrogen boilers offer potential solutions however, the intricacies of deployment and installation are complex, further research and development is required to learn more about installation, performance of various heating options. Doing so will inform future domestic decarbonisation strategies.

The Gas Network Evolution Simulator (GNES) is an innovative project aimed at optimising the transition away from natural gas by using advanced Agent Based Modelling (ABM). GNES simulates the complex interactions between stakeholders such as Gas Distribution Networks (GDNs), Electricity Networks, consumers, and policymakers. It analyses economic, social, and environmental impacts of gas network decommissioning and explores new infrastructure opportunities. By identifying challenges and benefits, GNES supports the development of cost-effective, equitable solutions that support vulnerable populations, ensuring a smooth transition to low-carbon energy sources while minimising consumer disruption and maximising network efficiency.

As the energy system transitions away from unabated natural gas and parts of the gas network are either decommissioned or repurposed to support the UK’s net zero goals, there is an increased risk of unintentional third-party damage to the network. Any supply interruptions to the transmission network would directly impact security of supply across the country and have a significant cost to customers including power generators, industry and domestic users. This project will investigate the benefits of moving from expensive, low frequency, manual network inspections to innovative AI assisted surveillance technologies in combination with satellite imagery and drones.

This project will focus on barholing operations conducted after an emergency gas escape within the H100 Fife Distribution Network Operations. The scope will consider H100 scenarios, specifically the establishment of a new distribution network to deliver Hydrogen to selected properties in the conversion area. The minimum pressure for the H100 Fife Distribution network is 27 mbar, and the maximum pressure is 75 mbar. The aim of this project is to provide further evidence to support SGN operations on the H100 distribution network during emergencies and any future trials or broader rollouts of Hydrogen.

Steer Energy has been identified as a suitable contractor for executing this project due to their extensive expertise in this field and their previous work on the Barhole Trials and ITL Haldane Drill Isolator project. Steer has a proven partnership with SGN and the wider gas industry, offering a variety of services, including experimental lab testing, training, and testing facilities.

This project will explore the feasibility of integrating hydrogen train refuelling infrastructure to support the development of a hydrogen rail network. This has particular relevance to our network as some of the UK’s hardest to electrify rail routes are situated in Wales and South West England. The project will focus on these hard to electrify routes, exploring H2’s potential role in enabling their decarbonisation. If successful, this project can help the WWU network to become a proving ground for real-world delivery of impactful H2 rail technology. It is expected to provide information which can be used in planning strategic hydrogen pipeline routes and network repurposing plans, and support regional energy planning.

National Gas Transmission (NGT) own and operate the UK’s National Transmission System (NTS), transporting natural gas from terminals to end users. NGT have ambitions to repurpose the existing to transport hydrogen and hydrogen blends. Understanding the impact of hydrogen on our existing assets is a key enabler for this.

This project will conduct design of flare for hydrogen and its blends and vent system for hydrogen, its blends and carbon dioxide and offline physical testing to provide evidence that hydrogen / hydrogen blends could be flared and vented safely and environmentally in for NTS.

This project assembles a multi-laboratory team to address high-priority research topics identified by industry related to the blending of hydrogen into the U.S. natural gas pipeline network. PRCI has been contracted by DOE to provide contract and invoicing support which allows additional members to join after project start.

There were four main activities being performed in Phase 1 of the CRADA project that fell under two categories: materials research and analysis. Sandia National Laboratories (SNL) led the materials research on metals, which is primarily used for natural gas transmission, while Pacific Northwest National Laboratory (PNNL) headed the research on polymeric materials, which comprise the natural gas distribution network. Argonne National Laboratory (ANL) was responsible for life-cycle analysis while the National Renewable Energy Laboratory (NREL) performed techno-economic analysis on hydrogen blending scenarios, the work on these subjects will be extended in Phase 2.

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

Project will deliver strategic analysis and recommendations to support the accelerated adoption of Hybrid Heat Systems (HHS) in GB. This includes assessing technology options, commercial models, stakeholder perspectives, and system integration pathways. The work will result in actionable insights, clear positioning of HHS within the wider decarbonisation strategy.

This project proposes a structured approach to assess the integrity of AGI pipework for hydrogen service. It includes development of a screening tool based on representative AGI archetypes, execution of ECAs to define flaw tolerances and inspection intervals, and evaluation of NDT capabilities with respect to desired AGI performances. The project also reviews integrity management software to support increased digitalisation and monitors emerging technologies for hydrogen-related NDT developments.

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.

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:

1. 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.
2. 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.
3. To identify opportunities for changing equipment items to simplify recharging/refuelling requirements in future.
4. 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.

The key subject of HIRSA stage 2 projects is to understand if using hydrogen in the gas network will result in an increased likelihood of ignition from static discharge generated by particulates in flowing gas. Building on stage 2A, stage 2B will provide further experimental testing aimed at determining the absolute difference in electrostatic charge generated, identify whether any external factors impact one gas more than the other, and to control the factors affecting generation of the charge. The outputs of this work should provide the industry with a better understanding of the potential change in ignition risk when switching from Natural Gas to hydrogen and will also highlight relevant mitigations to manage this risk.

This project is looking to address uncertainties surrounding LTS pipeline materials by investigating the effect of the oxide layer on hydrogen permeation rate for steel pipelines. This project will also investigate the formation of an oxide layer inside the pipe at different temperatures, as well as how the microstructure of the pipeline steel and condition of the oxide layer affect permeation for different grades of steel. It is critical this relation is better understood as these uncertainties are currently hindering our ability to fully and accurately assess the repurposing of the LTS. The outcomes of this project have the potential to increase cost-savings and improve confidence in the existing network to carry hydrogen, including blends.

This project will help WWU to understand considerations for 100% Hydrogen Rollout at a town scale, to inform future activity on preparation for repurposing. Areas will be chosen which are representative of different networks, housing stock and demographics, which will require different approaches and engagement.

In order to support UK ambitions for hydrogen blending and the development of a hydrogen economy, National Gas will need to install new gas chromatographs with the capability to measure hydrogen up to 20% in a natural gas blend. At present hydrogen is not measured anywhere on the National Transmission System (NTS), and therefore there are no proven in-use devices, and limited experience within the company to allow effective decision making in deploying these assets in the move towards net zero.

In order to make informed decisions ahead of chromatograph fleet upgrade, and to allow for a wide selection of reliable device choices when it comes to that upgrade, National Gas require the testing of available devices to analyse their performance, and thus suitability for NTS installation. This project will employ a trusted testing house to obtain (through loaning) blend-ready chromatographs from suppliers, and then to rigorously examine the performance of those devices. These devices could be tested at the testing house’s site, or at the instrument vendor’s site.

As part of National Gas’s Three Molecule strategy, the technical evidence for the transportation of hydrogen and carbon dioxide through the National Transmission system is being gathered through the HyNTS and CO₂ programmes. This technical evidence will feed into the updates of NGT’s suite of policies and procedures which are used to demonstrate compliance with the Gas Safety (Management) Regulations (GSMR), Pipeline Safety Regulations (PSR) and Pressure System Safety Regulations (PSSR).

This project will develop the approaches to compliance with regulations for hydrogen, hydrogen blends and CO₂, considering both new build and repurposed assets. The project will also define how the NTS Safety Case of the future will look, including modular design and digitalisation to streamline access to information.

Existing defect assessments and repair methodologies are aligned with the T/PM/P/11 and T/PM/P/20 management procedures and are adopted to inspect, assess and repair the pipelines for defects and take suitable measures to reduce them. However, the scope and applicability of the repair techniques in the presence of high-pressure hydrogen remain uncertain. The key questions which form an outline of the project are:

1. What are the different types of defects, we may encounter or consider injurious in the presence of hydrogen?
2. What is the impact of hydrogen on each defect type? Have the mechanisms of failure changed for each defect type after hydrogen-natural gas blending?
3. Will the existing repair techniques be applicable under transmission of high-pressure hydrogen and hydrogen-natural gas blends?
4. Can we implement the defect assessment, inspection and repair methodologies safely? Are the techniques safe and suitable for the pipeline operations and maintenance teams?

The project seeks to answer the above in addition to understanding the types and extent of repairs across the NTS and assess the impact of hydrogen on the effectiveness of these inspection, assessment and mitigation technologies.

This project investigates the technical and economic feasibility of converting non-domestic buildings from natural gas to low carbon energy sources, specifically hydrogen and electricity. It aims to address the significant evidence gap around the conversion of commercial and institutional buildings that are currently supplied by the GB gas distribution networks. The study will assess a wide range of building archetypes, including care homes, schools, hospitality venues, and light industrial sites, using a combination of literature review, site surveys, detailed system designs, and technoeconomic modelling. The outputs will inform future energy policy, support infrastructure planning, and help ensure safe and cost-effective deployment of low carbon technologies in non-domestic settings.

This project constitutes a research study exploring innovative opportunities to repurpose decommissioned gas pipelines and associated assets to support future energy systems and critical infrastructure needs.

By exploring diverse repurposing options beyond hydrogen and carbon dioxide, it is hoped that it will be possible to identify potential growth areas for gas pipeline assets that in some areas may otherwise become stranded. The study will include a review of economic viability, technical feasibility, and regulatory considerations for any identified options.

Situation:

As National Grid ESO transitions to the NESO it will take on the role of Regional Energy Strategic Planners, which will bring a focus on the alignment of Local Area Energy Plans and distribution network planning.

Complication:

Current regional distribution network future energy scenarios are produced by electricity distribution networks. Gas distribution networks do not have an equivalent activity Accordingly, regional and local area energy planning in not informed by a balanced consideration of all energy vectors.

Solution:

An agile and easy to use Whole Energy Systems Pathway (WESP) tool, with detailed temporal and spatial investment planning capabilities, to enable a regional whole energy system planning capability which informs gas network planning, as well as inform national, regional and local planners, in an objective, evidence based. way

This project will help Cadent to understand considerations for a Net Zero Multi-Vector at a town scale, to inform future activity on preparation for repurposing. An area will be chosen which is representative of different networks, housing stock and demographics, which will require different approaches and engagement.

UK gas networks are managed and maintained using an extensive suite of policies, policies standards and procedures. These documents have been developed gradually over decades of gas network operation, however the transition to hydrogen necessitates a wholesale review and update of all existing documents. There is much commonality between the networks’ documents and therefore it would be most efficient to update these documents in a coordinated way to avoid the unnecessary duplication of effort.

As part of the National Gas Network Performance Twin program, this project is designed to demonstrate a scalable digital twin platform focused on improving infrastructure resilience, supporting hydrogen integration, and addressing climate adaptation across the National Transmission System (NTS). This initiative integrates three strategic components: Collaborative Visual Data Twin (CVDT) – a 3D BIM-based digital twin platform that visualises and monitors asset performance in real time. HyNTS Dataset Automation – a structured, automated geodatabase that supports hydrogen readiness assessments and asset integrity modelling. Flood Twin – a predictive flood simulation model that enables scenario-based risk analysis and resilience planning for Above Ground Installations (AGIs).

This project will update the Pathfinder tool, to improve functionality and reflect more current underlying data. Use of the tool developed in this project should result in better choices regarding investment in energy saving measures

The Unaccounted-for Gas (UAG) project aims to develop a predictive tool that identifies and quantifies UAG across the National Transmission System (NTS). Leveraging 12-18 months of SCADA data, the tool will simulate gas flow and metering behaviour to pinpoint anomalies and reduce losses. UAG currently represents significant financial cost to the consumer; even a 1% reduction could yield practical savings. The project aligns with RIIO-2 NIA criteria and supports regulatory compliance under Special Condition 5.6. It builds on prior research, and integrates learnings from international benchmarks. The initiative will enhance operational efficiency, improve data transparency, and support long-term decarbonisation goals through better system visibility and control.

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 inspection methods do not routinely inspect girth welds for defects. Deterministic defect assessment models require the use of conservative assumptions for defect sizes, material properties and loading. This can lead to overly pessimistic conclusions about the suitability of pipelines with girth welds for use with hydrogen.

More detailed probability-based assessments are required to reduce the inherent pessimism in deterministic calculation methods. This would provide confidence of the safety and allow for greater use of the LTS with hydrogen and contribute to a quicker and cheaper energy transition for the UK gas network.