Net zero and the energy system transition

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.

This project will investigate the potential impacts of district heating on the gas network whether its viable for the network to support district heating and what repurposing would be required.

This project will build upon previous work to inform decisions relating to the repurposing of National Transmission System pipelines for 100% hydrogen and hydrogen-natural gas blends. New input data will be generated and collated the assessment methodology will be refined and an alternative assessment method probabilistic will be utilised and the resulting network impact will be considered.

This project will generate the following benefits:

• More accurate assessment of the capability of the NTS to transport 100% hydrogen and hydrogen-natural gas blends.
• Data on the impact of low percentage blend hydrogen on pipeline materials.
• Standardised document for Engineering Critical Assessments (ECA) of hydrogen and hydrogen-natural gas blend pipelines and pipework.

Greater understanding on the effect of hydrogen on the design and operation of pipeline systems.

The project described covers the development of a new repurposing process for NTS assets to transport gaseous phase carbon dioxide. The approach for repurposing the National Gas Transmission System (NTS) to transport carbon dioxide will need an innovative approach to meet the timelines for the net zero transition. There have been several projects undertaken to date to determine the interactions of carbon dioxide with the network assets. We are looking to determine if these activities are providing all the relevant data and evidence required for our network to transition.

This Network Innovation Allowance (NIA) project investigated dew point management in hydrogen/natural gas blends pure hydrogen and carbon dioxide transmission pipelines. In the National Transmission System (NTS) which is currently a natural gas network the purity of the gas is carefully controlled via the network entry specification. Trace components such as water nitrogen oxides sulphur containing compounds oxygen and carbon dioxide have strict limits on their allowable levels in the network. This is done in part to ensure the gas delivered to end users meets the requirements of the customer but also to protect transport and storage systems. Purity specifications are being developed for hydrogen its blends with natural gas and for carbon dioxide (CO₂). This project focused specifically on the water content within these gases in what concentrations it is likely to be acceptable the conditions at which it may condense in the network its interactions with other trace components and contaminants and the potential detrimental effect on the network.

Limiting moisture content and ensuring gas dryness is important for several reasons:

• Safety & Efficiency: Hydrogen’s efficiency as a fuel can be compromised by moisture. Water in hydrogen can affect the combustion process leading to a reduced efficiency for applications like gas turbines.
• Corrosion: If dew points aren’t controlled effectively liquid can drop out of the gas phase and this moisture can cause corrosion in pipelines and hydrogen embrittlement. For CO₂ pipelines this moisture can react to produce carbonic acid which can further corrode the pipelines.

The outcomes of the project should provide a clearer insight and strategy on how to effectively manage hydrogen and carbon dryness within the NTS ensuring that the gas remains within the required specifications for current and future demands.

The project was split into three work packages (WP):

1. WP1 focused on hydrogen and its blends initially reviewing the equations of state (EoS) that model the dew point temperature at varying water content and hydrogen/methane blend ratios. The impact on the network of liquid water formation in hydrogen was examined including the interaction with other trace components such as CO₂ and H₂S in particular the effect on welds and pipeline defects. Finally a summary of international standards for hydrogen purity highlighted the likely water content limits that could be expected by hydrogen users and thus provided by producers.

2. WP2 focused on CO₂ its phase behaviour and the effect impurities have on this behaviour using the most appropriate equations of state. The detrimental effect of CO₂ and liquid water contained within it on pipelines fittings and other parts of the network was reviewed.

3. WP3 focused on how the water content specifications could be managed on the network from the point of view of monitoring and controlling water dew point in the gases. The water content expected from various production techniques were reviewed and a high-level costing for the dehydration process for both CO₂ and hydrogen was made.

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 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 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.

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.

Develop credible and independently modelled pathways to test the economic case of developing a H₂ Backbone and prepare NGT for dialogue with NESO DESNZ HMT and a wider group of stakeholders.

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.

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.

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.

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 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

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.

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

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.

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.

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.

The use of greener gases such as biomethane are an important part of the UK’s transition to net zero. Underground storage sites for biomethane are critical for balancing seasonal supply and demands for energy. However increased levels of oxygen in biomethane can lead to corrosion of assets in wet gas conditions compromising the integrity of storage facilities. This project will assess in a comparative analysis the technical and economic viability of advanced catalytic and adsorption technologies to reduce oxygen levels in biomethane with corrosion inhibitors to ensure the integrity and longevity of critical storage infrastructure.

Phase 1 of the project compiled a list of oils and greases considered to be gas-facing on the NTS along with identifying functional and material property requirements of these products. Proposed standards and testing methodologies were also outlined to inform the next phase of the project. In Phase 2 the project will proceed with additional required activities to ensure the safe utilisation of NTS oils/greases in a hydrogen pressurised environment. These activities include laboratory testing for lubricants and functional testing for sealants to assess degradation and performance of these products in hydrogen. Subsequently requirements for in-service monitoring will be identified.

Hydrogen design codes require fracture mechanics based design and qualification for high stress service. Procurement of a number of Long Lead Items (LLI) is required to construct commission and operate hydrogen networks. A number of these LLIs including induction bends and barred tees remain at a low technical readiness.

This project will carry out fracture toughness testing in a hydrogen environment to increase the technical readiness support the supply chain and achieve operational schedules.

The Stopple technology is a flow stop tool essential for major projects and emergency works across the LTS and NTS gas network. Its capability was tested in 100% hydrogen within a helinite environment in line with LTS Futures parameters as phase 1. This project focuses on validating flow-stopping technology as an additional deliverable with LTS Futures live hydrogen trial on the Granton to Grangemouth pipeline as a welded tee and hot-tapping operations is already being carried out. The trial will confirm the Stopple train’s effectiveness as a double-block and bleed solution for a 100% hydrogen system which will be available for the UK Gas Network. The findings will provide critical insights into the safe and efficient operation of the hydrogen networks supporting the transition from natural gas to hydrogen.

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.

Early cluster projects will not benefit I&C customers that are located away from industrial clusters and are traditionally more distributed in nature. These customers are unlikely to have access to hydrogen infrastructure developed through the primary industrial clusters. This presents the need for an alternative solution.

This project will explore the concept of how a larger number of low-volume hydrogen producers can support I&C customers in the absence of natural ‘clustering’ and high-volume production by using the South West region of WWU’s network as a case study. This will be done by exploring the whole systems concept of a gas network which is driven by distributed green hydrogen production at strategic locations where there is access to both gas and electricity grid infrastructure.

To achieve decarbonisation targets all gas network operators in the UK need to demonstrate that the gas network can safely technically and economically facilitate the distribution of low-carbon gases (biomethane and hydrogen). In response to this challenge SGN aim to review the feasibility of the formation of biomethane islands in their Scotland area of operation. The outputs of this project will establish a business model for the optimisation of biomethane injection and formation of biomethane islands across the UK’s gas network. A feasibility study will address key areas including regulatory technical environmental social and commercial aspects as well as comprehensively assess the viability of developing Biomethane Islands. The outcome of the feasibility study will be to inform decision-making regarding project implementation. This will be captured and delivered in a comprehensive report and financial model of the business case. These islands will serve as models for sustainable living demonstrating the feasibility and benefits of a circular economy approach to energy production and waste management and offer a low disruption option for the decarbonisation of all classes of gas consumers - Industrial Commercial and Domestic.

The project will evaluate and deliver a plan that ensures our asset records are suitably complete to support the net zero transition.

The project will reduce uncertainty and risk and provide a more realistic proximation of asset data.

The HSE has indicated that it will be unable to support a network’s hydrogen safety case until they receive “a clear plan for checking unknown assets and how networks will ensure that only suitable materials are present in the network”. This includes our transmission pipelines.

Additionally for the marginal extra effort it would be prudent to ensure the completeness of our asset records is sufficient for us to either plan for the conversion to hydrogen or decommission sections as users switch to other heating technologies.

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.

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 1400 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.

Decarbonisation of UK transport and the related Zero Emission Vehicle (ZEV) mandate requires companies to transition their commercial vehicle fleets to Battery Electric Vehicles (BEV) or alternative new emerging technologies (e.g. FCEC). As an operational utility network with responsibility for public safety WWU’s fleet undergoes a more challenging and varied range of duty cycles than most commercial fleets includes vehicles that are required to provide on-site power and must be capable of meeting WWU’s statutory duty to respond quickly to Public Reported Escapes.

Within this challenging operational context WWU must deliver a fleet transition at the lowest feasible cost to assure value for money for our customers. This is further complicated by the need to plan the fleet transition while the associated technological and policy landscape continues to evolve in parallel. Although the learnings generated from the project will be specific to WWU’s fleet as a case study they will be applicable to any networks with an operational fleet.

To assure a cost-effective transition and derisk future operations WWU require a Total Cost of Operation (TCO) model. This will be specifically targeted at our particular operational context capable of assessing the costs and capabilities of a range of ZEV options and crucially must be easy for staff to adopt for internal use and update in the future as new data and/or technologies become available.

The purpose of this project is to provide WWU with a TCO model that addresses our specific operational requirements ensuring that plans and investment decisions will be grounded in real-world technology assessments and our operational fleet data.

Based on previous work ROSEN Engineers believe the quantity of natural gas vented during commissioning operations can safely be reduced by up to 80% through targeted changes to direct purging procedures.

For Gas Distribution Networks’ (GDNs) gas venting remains a necessary part of normal operations for maintenance or safety purposes. Previous research work undertaken by ROSEN(UK) Limited for the EIC with project partners Northern Gas Networks (NGN) and Wales and West Utilities (WWU) identified activities where venting of natural gas to atmosphere occurs (Gas Venting Research Project NIA reference number NIA_NGN_282)

Wales & West Utilities has developed a Regional Decarbonisation Pathway to provide an overarching strategic plan for the network in Wales and the South West of England. To deliver that pathway more detailed assessment and planning is required to facilitate the progression of opportunities in particular areas.

In 2023 WWU supported Cadent as the lead partner in the development and delivery of a Functional Blending Specification (FBS) which has progressed the technical understanding of how blending equipment can be practically applied within the context of existing gas network assets (https://smarter.energynetworks.org/projects/NIA_CAD0079/). In 2023 UK Government affirmed their support for network blending whilst networks have continued to develop evidence in support of blending since (Hydrogen blending in GB distribution networks: strategic decision - GOV.UK (www.gov.uk)).

As the owner of the National Transmission System (NTS) National Gas is committed to responsibly managing our redundant assets in a manner that contributes to a sustainable lower-carbon future by decommissioning them responsibly refurbishing for re-use where viable and/or or changing their purpose where possible. This discovery project will identify decommissioned elements of redundant pipework on the transmission system which are unlikely to be used for refurbishment or part of any wider repurposing of the core network and explore the potential of repurposing these for alternative uses including the storage and/or transmission of electrical energy heat fuels water and data.

FutureGrid CO2 is the final phase of a suite of Carbon Dioxide projects looking at how National Gas can repurpose parts of its network to transport gaseous-phase Carbon Dioxide safely. What started out as literature reviews and feasibility studies will turn into physical testing and demonstration. National Gas will be using its world-leading FutureGrid facility to demonstrate how Carbon Dioxide will flow through its pipes delivering on its promise to further use this facility after our successful FutureGrid SIF Beta projects. We will also be completing carbon dioxide venting ruptures and real-time impurity corrosion tests- all of which are underexplored.

Following the work completed on the policies and procedures project by QEMS WWU have identified the requirement to update and re-vamp the existing Safe control of operations (SCO) procedures used by the network to support delivery of upcoming projects.

The following is a proposed outline for a report on the decarbonisation benefits and potential of biomethane in the UK Road Haulage sector.

The report will position biomethane as:

1. A complimentary technology to zero tailpipe emission vehicles that offers faster decarbonisation potential due to the near-term infrastructure scalability of the technology and the suitability for long distance and non-fixed route logistics.
2. A cost-effective way to reduce Carbon emissions by over 84% over the next 15-20 years whilst zero tailpipe emission technologies are developed and the supporting infrastructure is deployed.
3. An enabler to the transition to zero tailpipe emission vehicles by offering reduced carbon abatement costs that in turn can generate funds to invest in zero emissions infrastructure and vehicles.

It will serve as a reference document for discussions with industry stakeholders governments and regulators.

This project will undertake testing on technology for distributed production of low carbon hydrogen from natural gas biogas or other short chain hydrocarbons from waste. Which uses 90% less electricity than electrolysis of water and with 68% lower total energy costs.

The project will support early movers and convert gas from our network into a low carbon hydrogen solution. The compact and modular deployment of the technology enables hydrogen production systems to be installed directly at the energy user's site. These systems convert grid-supplied natural gas to hydrogen on demand eliminating the need for additional infrastructure or on-site hydrogen storage and leaves the rest of the network unaffected

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.

Analysis of the distribution networks undertaken in the H2 Caledonia and H2 Connect projects has identified sectorisation isolation as the optimal approach for conversion. Sectorisation isolation allows for a sector-by-sector approach ensuring the gradual conversion of existing Natural Gas connections over to hydrogen or managing the disconnection process should customers opt for alternative heating solutions. This project will aim to develop an understanding of the technical and financial feasibility of a Flexible Gas Transition Plant (FGTP) through primary project outputs such as: outline of design options development of a list of transition use cases a cost benefit analysis (CBA) for each transition scenario and a roadmap for future phases including prototype design and trials.

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.

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 LTS Futures project aims to understand how the local transmission system (LTS) could be repurposed from Natural Gas to hydrogen. The project encompasses several elements which will feed into a blueprint methodology for repurposing the LTS to hydrogen. During one of the work elements LTS Futures conducted full-scale testing of pipeline defects and small-bore connections exposed to hydrogen. Testing was conducted until failure to provide information for hydrogen pipeline design standards and operational procedures. This project will undertake further detailed analysis of the fracture surfaces to provide a visual confirmation of hydrogen diffusion into the pipeline microstructure and if this contributed to failure.

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 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 project aims to explore the impact of hydrogen blends (in natural gas) 100% hydrogen and carbon dioxide on contaminants (arisings) likely to be found in gas transmission pipelines (e.g. Naturally Occurring Radioactive Materials (NORMs) dusts mill scale welding slag glycols water BTEX methanol heavy metals sulphur compounds pyrophorics as well as rotating machinery lube/seal oils and valve sealants etc).

The project will aim to understand the current composition and characteristics of any contaminants the impact of hydrogen and carbon dioxide on the behaviour/composition/presence of contaminants establish how long methane related contaminants will persist on the network (for repurposed pipelines) the potential for contaminants to cause pipeline gas to go ‘off-spec’ and the implications of contaminant interactions on National Transmission System (NTS) operation/integrity.

This project will conduct market research on available or soon to be available hybrid products for discussion and presentation back to WWU and WW Housing to choose a preferred solution for the properties identified that are suitable to trial the equipment in. The project will provide networks with demand data and look to aggregate this over WW Housing stock to understand wider impact on gas networks if this was considered a viable option to decarbonise housing stock.

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 assess the current and future role of gas distribution networks (GDNs) in supporting dispatchable electricity generation within a decarbonising UK energy system. It will identify method(s) for GDN operators to obtain accurate gas usage data from existing generation connections and develop future scenarios to inform network planning and investment.