Net zero and the energy system transition

This project involves a comprehensive set of tasks aimed at implementing and validating a domestic safety system for hydrogen use including excess flow valves.

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 will explore ventilation and explosion relief requirements for housing currently used on the gas network for pressure regulating installations (PRIs). Housings currently provide security from a range of factors from weather to vandalism while also providing the necessary relief requirements in the event of an emergency. The understanding of these requirements for Natural Gas has been developed however work conducted in the IGEM TD/13 hydrogen supplement did not fully address whether these design specifications are suitable for use with Hydrogen. This multi-stage project will first explore the design specifications listed in industry standards (IGEM/TD/13 GIS/PRS/35 SGN/SP/CE/10 etc) and understand which of these may be appropriate and which may require redesign. The latter stage of this project will take the design specifications deemed to be unsuitable for use with hydrogen and conduct testing to develop revised design specifications which would provide the necessary relief requirements.

Existing defect assessments and repair methodologies are aligned with the P/11 P/20 and PM/DAM1 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 these assessment and repair methodologies in the presence of gaseous phase carbon dioxide remain uncertain. The key challenges which the project aims to address are:

• Will existing repair techniques such as epoxy shell welded shells composite wraps gouge dressing etc. be suitable for transmission of gaseous phase carbon dioxide?
• What are the different defects we may encounter or consider hazardous in the presence of carbon dioxide? What are the impacts of carbon dioxide on each defect type? And how much does water/corrosion exacerbate this?
• Have the mechanisms of failure for each defect type changed after introducing carbon dioxide?
• Can we implement the assessment 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 review the impact of carbon dioxide on the effectiveness of these inspection assessment and mitigation technologies.

This project concerns the research into welding residual stress values and the effect that they have on the overall pipework repurposing assessment route described in relevant hydrogen standards. Currently overly conservative values need to be applied for welding residual stresses in any repurposing assessment. This project aims to build evidence on actual and modelled residual stresses seen within the pipelines industries with a focus on natural gas pipelines. As the welding residual stress is a critical aspect of the fracture mechanics assessment any improvements which can be gained would have an overall positive impact on the assessment results.

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 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.

The statistical ‘value’ (i.e. risk reduction and cost) of remote hydrogen detectors has been determined through statistical based projects as part of the hydrogen heating programme (HHP). The cost has been shown to outweigh the risk however given hydrogen is not a mature heating solution the cost can be justified in response to risk appetite from key stakeholders such as consumers. This risk appetite is assumed. There is currently no analysis (qualitative or quantitative) into consumers attitudes towards the ‘value’ of remote detectors. This project will begin to explore the perception of risk reduction from remote detectors to be used to compliment the statistical based analysis to paint a fuller picture towards the utilisation and crucially the value of remote detectors.

National Gas has seen a significant increase in the number of enquiries from biomethane developers for connections to the NTS.

There are currently circa 66 projects the connections team have identified as having NTS connection potential with an associated volume of 5.9TWh per annum.

Developers are attracted to the NTS for numerous reasons but the following are the main drivers:

• No injection of propane or odorant
• Capacity and capability

To speed up time to connect to a biomethane facility this project was developed to produce an innovative standardised design for a Minimum Offtake Connection (MOC) in a pit.

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.

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.

National Gas are investigating the use of the National Transmission System to transport hydrogen and hydrogen blends. To support this research and testing is required to understand the risks of high pressure hydrogen transmission including ignition. This project will identify for 100% hydrogen and blends of hydrogen up to 20% the sources of ignition including how the distance of ignition sources affects the likelihood of ignition. It will also investigate the frequency and the different types of ignition events e.g. jet fires. Lastly it will look at the probability of ignition on sites and in pipework.

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.

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.

As the UK attempts to decarbonise residential heat to meet net zero by 2050 electric heat pumps along with heat networks are expected to play a key role. However it is generally accepted that no one technology will be able to meet the needs of all households. If we are to deliver affordable low- carbon heating in the residential sector we shall need as wide a range of technology options as possible to overcome the economic and technical challenges facing every customer.

Project GaIN (Gathering Insights) will explore alternatives to heat pumps and heat networks which can utilise the robust gas network and benefit from its current upgrade programme supporting the aims of DESNZ’s decarbonisation of heat roadmap. The project will discover and assess additional technology options where alternative solutions might be more costly or difficult to deliver; this will include LAEP system benefits as well as localised CAPEX and OPEX costs.

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.

This project will examine the suitability of existing Fire and Gas (F&G) detection and suppression systems for use with hydrogen blends of up to 20%. These systems comprise: fire detection fire suppression gas detection and associated control systems. They are found in compressor cabs and at network terminals.

Through CFD modelling three representative F&G systems will be individually assessed for compatibility with blends and will then be used as examples to make comments on the suitability of other F&G systems on the network. Where assets or control systems are not suitable this project will not design a new system but recommend where changes should be made and demonstrate how those changes safely manage risk – including cost estimation for upgrade or retrofit.

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.

This project will help to provide assurance to UK Gas Distribution Network Operators (GDNOs) and wider industry on the safe design of domestic gas appliances in a future where hydrogen is being distributed in network pipelines. A risk to the normal safe operation of appliances under 100% hydrogen operation exists where a flammable hydrogen/air mixture is supplied to the appliance creating the potential for flashback to occur within the gas installation pipework. This work will provide assurance that domestic appliances designed to operate on 100% hydrogen are designed in a way which do not enable flashback to occur.

The project will also investigate the long-term feasibility of installing an auto-locking Emergency Control Valve (ECV) at the end of 100% hydrogen networks to ensure that any reinstatement of supply after a period of isolation can only be undertaken by a competent gas engineer.

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.

This project will deliver a series of reports and presentations which reflect the need to minimise disruption during any conversion taking into account customer needs and the wider supply chain not just the needs of the GDN.

Clean Power 2030 (CP2030) aims for a fully decarbonised electricity system using unabated gas only as backup. This introduces an important challenge: how can the gas transmission network remain viable and deliver flexibility during extreme demand events despite not being utilised most of the time? This project aims to understand how to sustain the gas network technically and economically in a low average high peak demand future focusing on the interaction between gas and electricity systems.

This project has been initiated to assess the technical and commercial feasibility of direct hydrogen injection into the gas distribution network at 5% and 20% by volume. It supports the broader Market Frameworks appraisal by providing the evidence needed to evaluate whether both System Entry Models direct injection and pre-blending are feasible under varying network conditions.

The need for this study was identified through the Hydrogen Blending Implementation Plan which outlined two technical approaches for hydrogen connections: injecting hydrogen directly into the network or pre-blending it before entry each with distinct technical and commercial implications. While National Gas has assessed both models for the transmission network a gap analysis revealed that these findings are not directly transferable to the distribution network.

Evidence for pre-blending was previously completed as part of HyDeploy and the Hydrogen Blending Functional Specification project. It was shown that this approach provides more controlled mixing but may require more complex infrastructure leading to higher costs for the producer. Although it is assumed Direct Injection may be achievable at lower cost there are multiple key technical challenges associated with the technique such as the potential for inadequate hydrogen mixing which could result in non-compliant gas safety concerns including material integrity and operational constraints e.g. GSMR exclusion zones.

Through literature review CFD modelling engineering assessments and commercial analysis the study will evaluate the technical and safety performance risks and cost implications of direct injection across a range of scenarios and configurations.

Novel green molecules have the potential to make a significant contribution to the decarbonisation of the UK’s gas network while also reducing system costs. Synthetic and e-methane can play a significant role in meeting future industrial demand as well as decarbonising the power transport and domestic heat sectors. This project investigates novel green gases in more depth to understand how they can be implemented effectively and quickly deployed to decarbonise the gas sector in the UK.