Projects & Initiatives

The Health and Safety Laboratory (HSL) has carried out an investigation into the gas characteristics that may influence the leakage dispersion and flammability hazards associated with blended natural gas-hydrogen mixtures containing up to 20 % mol/mol hydrogen. The work was carried out under contract to Cadent & Northern Gas Networks as part of the HyDeploy project which was commissioned to investigate the feasibility of using blended hydrogen-natural gas mixtures in UK mains gas distribution networks.

Under the HyDeploy project a demonstration scheme is being carried out at Keele University in which it is planned to inject up to 20 % mol/mol hydrogen. Keele is Britain’s largest campus university and an ideal test site for a demonstration scheme as its gas distribution network is largely independent of the national gas network but still subject to UK gas industry procedural controls. It is anticipated that a successful demonstration scheme will facilitate the use of blended natural gas-hydrogen mixtures throughout the UK leading to significant reductions in carbon dioxide emissions. The project is being led by Cadent & Northern Gas Networks and also involves ITM Power Progressive Energy Keele University and HSL in consortium.

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A consortium comprising Cadent Northern Gas Networks Keele University Health and Safety Laboratory ITM Power and Progressive Energy is undertaking the research project HyDeploy. The project funded under the UK Network Innovation Competition scheme aims to demonstrate that natural gas containing levels of hydrogen beyond the upper limit set out in Schedule 3 of in the Gas Safety (Management) Regulations (GSMR) can be distributed and utilised safely and efficiently in a section of the UK distribution network. It will conclude with a field trial in which hydrogen will be injected into part of a private gas distribution system owned and operated by Keele University. Dave Lander Consulting Limited and Kiwa Ltd are providing technical support to the HyDeploy project and this report presents the results of Quantified Risk Assessment (QRA) for the proposed field trial. The QRA is intended to support an application by Keele University for exemption from the legal requirement to only convey gas that is compliant with the requirements of Schedule 3 of the GSMR. The QRA is aimed at demonstrating that the field trial will not result in a material increase in risk to persons within Keele University affected by the proposed field trial.<br/>Check the supplements tab for the other documents from this report

HyNet North West is a significant clean growth opportunity for the UK. It is a low cost deliverable project which meets the major challenges of reducing carbon emissions from industry domestic heat and transport.<br/>HyNet North West is based on the production of hydrogen from natural gas. It includes the development of a new hydrogen pipeline; and the creation of the UK’s first carbon capture and storage (CCS) infrastructure. CCS is a vital technology to achieve the widespread emissions savings needed to meet the 2050 carbon reduction targets.<br/>Accelerating the development and deployment of hydrogen technologies and CCS through HyNet North West positions the UK strongly for skills export in a global low carbon economy.<br/>The North West is ideally placed to lead HyNet. The region has a history of bold innovation and today clean energy initiatives are thriving. On a practical level the concentration of industry existing technical skill base and unique geology means the region offers an unparalleled opportunity for a project of this kind.<br/>The new infrastructure built by HyNet is readily extendable beyond the initial project and provides a replicable model for similar programmes across the UK<br/>Contains Vision statement 2 leaflets a presentation and a summary report which are all stored as supplements.

The objective of the analysis is to provide a robust assessment of the economic impact of HyNet NW over the period to 2050 across both the North West of England and the UK as a whole. Impact is assessed through modelling of direct indirect and induced effect frameworks:

• Direct effects – activities that directly accrue due to the construction and operation of the facilities;
• Indirect effects – the purchase of goods and services to facilitate construction/operation; and
• Induced effects – spending of wages and salaries generated directly and indirectly through construction and operation.

The approach taken is to define the capital and operating expenditure (CAPEX and OPEX) profiles of the Project investment as the basis of analysis distinguishing where feasible between design construction and equipment costs and establishing the likely sourcing of these activities from within the North West UK and overseas.

Consideration is also given to the potential impacts of inward investment attracted to the North West/UK in the wake of the Project.

The THyGA project (‘Testing Hydrogen admixture for Gas Applications’) focusses on technical aspects and the regulatory framework concerning the potential operation of domestic and commercial end-user appliances with hydrogen / natural gas blends.<br/>The core of the project is a broad experimental campaign with the aim to conduct up to 100 hydrogen tolerance tests. In addition the technical status quo and present knowledge about hydrogen impact on domestic and commercial appliances are assessed and potential future developments of rules and standards are discussed. Also mitigation strategies for coping with high levels of hydrogen admixture will be developed. By this broad approach the project aims at investigating which levels of hydrogen blending impact the various appliance technologies and to which extent in order to identify the regime in which a safe efficient and low-polluting operation is possible.<br/>The series of public reports by the THyGA project starts with several publications from work package 2 which sets the basis for the upcoming results and discussion of the experimental campaign as well as mitigation and standardisation topics.<br/>This report D2.5 completes the series of public reports from work package 2. It explains the steps of development of the test programme for gas-fired appliance tests with hydrogen admixture and especially describes the exchange between the THyGA partners and the external stakeholders.<br/>The report also explains the process of acquisition of appliances to test and method of selecting appliances.

The trial management philosophy of the Winlaton trial within HyDeploy2 has been developed to enable the overall objectives of the project to be achieved; the safe demonstration of operating a Gas Distribution Network (GDN) on a blend of natural gas and hydrogen. The approach taken to develop the management philosophy of the Winlaton trial has been to continue the trial management strategies deployed for the Keele trial under HyDeploy albeit with site specific modifications where necessary. This document provides an overview of the management and governance processes associated with the trial itself.<br/>Click on the supplement tab to view the other documents from this report

Clean hydrogen is universally considered an important energy vector in the global efforts to limit greenhouse gas emissions to the "well below 2 °C scenario" as agreed by more than 190 states in the 2015 Paris Agreement. Hydrogen Valleys – regional ecosystems that link hydrogen production transportation and various end uses such as mobility or industrial feedstock – are important steps towards enabling the development of a new hydrogen economy.<br/><br/>This report has been issued during the setup of the "Mission Innovation Hydrogen Valley Platform"  which was commissioned by the European Union and developed by the Fuel Cells and Hydrogen Joint Undertaking. The global information sharing platform to date already features 30+ global Hydrogen Valleys with a cumulative investment volume of more than EUR 30 billion. The projects provide a first-of-its kind look into the global Hydrogen Valley project landscape its success factors and remaining barriers. This report summarizes the findings and presents identified best practices for successful project development as well as recommendations for policymakers on how to provide a favourable policy environment that paves the way to reach the Hydrogen Valleys' full potential as enablers of the global hydrogen economy.

Green Print -  Future Heat for Everyone draws together technical consumer and economic considerations to create a pioneering plan to transition 22 million UK homes to low carbon heat by 2050.<br/>Our Green Print underlines the scale of the challenge ahead acknowledging that a mosaic of low carbon heating solutions will be required to meet the needs of individual communities and setting out 12 key steps that can be taken now in order to get us there<br/>The Climate Change Committee (CCC) estimates an investment spend of £250bn to upgrade insulation and heating in homes as well as provide the infrastructure to deliver the energy.<br/>This is a task of unprecedented scale the equivalent of retro-fitting 67000 homes every month from now until 2050. In this Report Cadent takes the industry lead in addressing the challenge.

The Energy Research Accelerator (ERA) and the Birmingham Energy Institute have launched a policy commission to examine the state of play barriers challenges and opportunities for Energy from Waste (EfW) to form part of the regional energy circular economy in the Midlands. This policy commission explores the case for regional investment whilst helping shape the regional local government and industry thinking surrounding critical issues such as fuel poverty and poor air quality.

The Challenge

Tackling climate change is one of the most pressing issues of our time. To follow the path for limiting global warming below 2^ᵒC set out in the 2015 Paris agreement requires significant reduction in greenhouse gas emissions. The UK has committed to bring all greenhouse gas emissions to net zero by 2050 requiring action at a local regional and national level to transition to a zero carbon economy.

To decarbonise and decentralise the UK’s energy system we must implement technologies that provide energy supply solutions across the UK.

In the Midlands many industrial sites are unable to access supply of affordable clean and reliable energy to meet their demands.

Energy from Waste (EfW) could offer a solution to the Midlands based industrial sites. EfW sites provide affordable secure energy supply solutions that form part of a developing circular economy. EfW reduces our reliance on landfills and obtains the maximum value from our waste streams. There are a number of merging technologies that could potentially play an important role which treats waste as a resource properly integrated into an energy and transport system and fully respects the potential of linking in the circular economy.

Investment into EfW infrastructure in the region could lead to job creation and economic growth and could help provide inward investment needed to redevelop old industrial sites and retiring power stations. However for EfW to be part of a net-zero energy system (either in transition or long-term) technologies and processes are needed that reduce the current carbon emissions burden.

EfW could play a significant role in the net zero carbon transition in the Midlands supplying heat power and green fuels and solve other problems - the region has some of the highest levels of energy/fuel poverty and poor air quality in the UK.  The policy commission will help shape the regional local government and industry thinking surrounding this important topic.

Report Recommendations

Recovery Resource Cluster

The EfW policy commission proposes three major areas where it believes that government investment would be highly beneficial

• Building a network of local and regional Resource Recovery Clusters
• Creating a National Centre for the Circular Economy
• Launching an R&D Grand Challenge to develop small-scale circular carbon capture technologies.

The Resource Recovery Clusters (RRC) will be developed on post-industrial sites which could produce significant environmental economic and regeneration benefits. The RRCs combine a spread of EfW and recycling technologies with businesses that can consume their cheap electricity heat fuels CO₂ and material outputs.

The National Centre for the Circular Economy would analyse material flows throughout the economy down to regional and local levels and develop deep expertise in recycling and EfW technologies. The CCE would also provide expert guidance and support for local authorities as they develop local or regional strategies and planning frameworks.

The R&D Grand Challenge aims to make big advances in small-scale carbon capture technologies in order to turn 100% of CO₂ produced through the process of converting waste to energy into useful products. This is very important for areas such as the Midlands which are remoted from depleted oil and gas reservoirs.

The Programme Review Report ensures that the FCH JU programme is aligned with its strategy and objectives. This year the programme review was performed following a new procedure: it was carried out by the European Commission’s in-house science service the Joint Research Committee (JRC). The 2017 review pays particular attention to the added value effectiveness and efficiency of FCH JU activities. The review is structured around six panels under three pillars: transport energy and cross-cutting projects summarising the FCH JU Project Portfolio

This Meeting Report summarises the findings of a two-day workshop in April 2007 at the Culham Science Centre and Worcester College Oxford which explored the potential for large-scale Hydrogen production through methods other than electrolysis.<br/>Operating at the cusp of research and policy-making the UK Energy Research Centre's mission is to be the UK's pre-eminent centre of research and source of authoritative information and leadership on sustainable energy systems. The Centre takes a whole systems approach to energy research incorporating economics engineering and the physical environmental and social sciences while developing and maintaining the means to enable cohesive research in energy. A key supporting function of UKERC is the Meeting Place based in Oxford which aims to bring together members of the UK energy community and overseas experts from different disciplines to learn identify problems develop solutions and further the energy debate.

This 2nd deliverable from WP4 gives an overview of relevant existing certification experience on-going standardization activities and field trials in the European Union and other countries regarding gas appliances using H2NG. It gives a picture of the today’s situation as many of the identified initiatives are ongoing and progressing continuously.

The application of appropriate procedures in the downstream gas industry (defined as any works downstream of the emergency control value) is critical in protecting consumers of gas both domestic and commercial. The two primary standard setting bodies for the downstream gas industry are the British Standard Institution (BSI) and the Institution of Gas Engineers and Managers (IGEM). To ensure only competent engineers carry out works on a gas installation all gas businesses or selfemployed persons must become a member of Gas Safe Register as stipulated by the Gas Safety (Installation and Use) Regulations 1998 1 and each gas operative shall be included on the register and hold a valid license card that covers the areas of gas work they undertake. Membership of the Gas Safe Register is contingent upon demonstration of competency the recognised competency assessments are based on the relevant BSI and IGEM standards. Therefore the primary source of a gas operative’s competency to work on natural gas installations are the associated BSI and IGEM natural gas downstream standards.<br/>Investigation was undertaken to understand the potential implications of introducing 20 mol% hydrogen (H2) within natural gas supplies on the ability of gas operatives to competently carry out works. This investigation took the form of identifying all BSI and IGEM standards that could be applied on natural gas installations and reviewing them within the context of the known effects of introducing a 20 mol% H2 blend. Following review a series of technical questions were generated and responded to by the Health and Safety Executive Science Division. The responses provided were then reviewed and if considered necessary challenged to provide further information. The procedural review was led by Blue Flame Associates a body deemed sufficiently competent in downstream standards training certification and investigation. The report was subsequently reviewed by industry and feedback received. The industry comments were reviewed by the Project Team and where considered necessary the report was updated.

A consortiumcomprising Cadent Gas Health and Safety Executive – Science Division ITMPower Keele University Northern Gas Networks and Progressive Energy is undertaking the second phase of the research project HyDeploy. The project the first two phase ofwhich are funded under the UK Network Innovation Competition scheme aims to demonstrate that natural gas containing levels of hydrogen beyond the upper limit set out in Schedule 3 of in the Gas Safety (Management) Regulations (GSMR) can be distributed and utilised safely and efficiently in the UK gas distribution networks.<br/>The first phase of the HyDeploy project concludes with a 10-month field trial in which hydrogen will be injected into part of a private gas distribution system owned and operated by Keele University.<br/>The second phase of the HyDeploy project (HyDeploy2) continues on from the work of the first phase and is scheduled to conclude with two 12-month field trials in which hydrogen will be injected into public gas networks owned and operated by Northern Gas Networks and Cadent Gas.<br/>Dave Lander Consulting Limited is providing technical support to the HyDeploy project and this report presents the results of Quantified Risk Assessment (QRA) for the proposed field trial of hydrogen injection into part of a gas distribution system owned and operated by Northern Gas Networks (NGN) near the town of Winlaton in Gateshead Tyne and Wear. The QRA is intended to support an application by NGN for exemption from the legal requirement to only convey gas that is compliant with the requirements of Schedule 3 of the GSMR. The QRA estimates the risk to persons within the trial area affected by the proposed injection. A similar QRA1 was developed for the original HyDeploy field trial at Keele University.<br/>Click on the supplement tab to see the other documents from this report

In order to inform the Quantified Risk Assessment (QRA) and procedures for the Winlaton trial the HyDeploy 2 project has undertaken a second programme of work focused on assessing the safe operation of gas appliances with hydrogen blended gas. This work extends the initial programme of work undertaken in HyDeploy 1 in 2018. Collectively these two projects provide an evidence base to support the project objective to demonstrate that there are no overarching safety concerns for the addition of up to 20 % mol/mol hydrogen to the GB natural gas distribution network.<br/>Click on the supplements tab to view the other documents from this report

Transitioning to Hydrogen a joint report from five engineering organisations focuses on the engineering challenges of replacing natural gas in the gas distribution network with hydrogen in order to reduce emissions. The production of this report is timely following the commitment from Government this week to legislate for net zero emissions by 2050. It is expected that hydrogen will play a big part in the reduction of emissions from the heating transport and industrial sectors.<br/><br/>The report concludes that there is no reason why repurposing the gas network to hydrogen cannot be achieved but there are some engineering risks and uncertainties that need to be addressed. In the development of the report many questions were posed and members of IMechE IChemE IET and IGEM were surveyed to better understand the challenges faced by the hydrogen production and gas industries planning to undertake this ambitious transition. Further information was obtained from the Health and Safety Laboratories.<br/><br/>The report also highlights 20 ongoing projects in the UK that are looking at various aspects of hydrogen production distribution and use.

There is no inherent property of hydrogen that makes it unsuitable for metering at distribution or transmission pressures. Towns gas containing large percentages of hydrogen was used for many years in the UK and continues to be in use in Hong Kong and Singapore. Many manufacturers sell their ordinary mechanical gas meters as suitable for hydrogen in a laboratory or industrial situation; unfortunately lack of demand has meant that none of these meters seem to have certified under appropriate metering regulations for gaseous hydrogen (e.g. the Measuring Instruments Directive)<br/>Some of the more sophisticated modern inferential meters (e.g. thermal or ultrasonic) currently designed specifically for natural gas (or LPG if suitably calibrated) are likely to unsuitable for repurposing directly to hydrogen but none of the problems appear fundamental or insuperable. The largest potential hurdle probably surrounds the physical size of current meters. A hydrogen appliance will consume about 3.3 more hydrogen than natural gas (on a volumetric basis) and using traditional designs this would have been measured through a meter probably too large to fit within an existing meter box. Unless unsolved such an increase in size would add materially to any hydrogen re-purposing programme.<br/>The meter trade thus need to be challenged to come up with a hydrogen meter that is the same physical size as a natural gas meter on a power rating basis (i.e. in kW). Ultrasonic and thermal mass meters should be included in the necessary Research and Development programme.<br/>A meter test programme is suggested that will provide evidence to meter manufacturers that the metering of hydrogen is not inherently difficult and thus convince them to make the necessary investments and/or approach the GDNO’s for assistance with such a programme.

The Hy4Heat Safety Assessment has focused on assessing the safe use of hydrogen gas in certain types of domestic properties and buildings. The summary reports (the Precis and the Safety Assessment Conclusions Report) bring together all the findings of the work and should be looked to for context by all readers. The technical reports should be read in conjunction with the summary reports. While the summary reports are made as accessible as possible for general readers the technical reports may be most accessible for readers with a degree of technical subject matter understanding. All of the safety assessment reports have now been reviewed by the HSE<br/>Annex prepared to support Site Specific Safety Cases for hydrogen gas community demonstrations based on work undertaken by the Hy4Heat programme. It covers a collection of recommended risk reduction measures for application downstream of the Emergency Control Valve (ECV)

The Life Cycle Assessment (LCA) methodology is often used to check the environmental suitability of hydrogen energy systems usually involving comparative studies. However these comparative studies are typically affected by inconsistent methodological choices between the case studies under comparison. In this regard protocols for the harmonisation of methodological choices in LCA of hydrogen are available. The step-by-step application of these protocols to a large number of case studies has already resulted in libraries of harmonised carbon energy and acidification footprints of hydrogen. In order to foster the applicability of these harmonisation protocols a web-based software for the calculation of harmonised life-cycle indicators of hydrogen has recently been developed. This work addresses—for the first time—the validation of such a tool by checking the deviation between the available libraries of harmonised carbon energy and acidification footprints of hydrogen and the corresponding tool-based harmonised results. A high correlation (R2 > 0.999) was found between the library- and tool-based harmonised life-cycle indicators of hydrogen thereby successfully validating the software. Hence this tool has the potential to effectively promote the use of harmonised life-cycle indicators for robust comparative LCA studies of hydrogen energy systems significantly mitigating misinterpretation.

As 2018 marks the ten-year anniversary of the Fuel Cells and Hydrogen Joint Undertaking (FCH JU) it is inspiring to look back over the many accomplishments of the past decade. The projects described in these pages illustrate the approach of continuous learning exemplified by the FCH JU’s projects from creating low-carbon and sustainable solutions enabling market entry for new products developing ‘next generation’ products based on previous research to opening new markets for European expertise in fuel cell and hydrogen (FCH) technology.<br/>The FCH JU’s achievements are due in part to its multi-stakeholder structure: a public-private partnership between industry research and the European Commission. Industry-led research has pioneered new developments in FCH technology and brought many of them to the cusp of commercialisation. Market uptake from public authorities major companies and citizens alike has boosted confidence in these clean technologies establishing hydrogen as a cornerstone of Europe’s energy transition.<br/>DEVELOPING SOLUTIONS FOR A GREENER WORLD<br/>Citizens are at the heart of Europe’s Energy Union a strategy aimed at providing clean secure and affordable energy for all. For some years now and as a signatory to the Paris Agreement in 2015 the EU has been actively targeting reductions in carbon dioxide (CO2) emissions.

The UK Government signed legislation on 27th June 2019 committing the UK to a legally binding target of Net Zero emissions by 2050. Climate change is one of the most significant technical economic social and business challenges facing the world today.

The H21 NIC Phase 1 project delivered an optimally designed experimentation and testing programme supported by the HSE Science Division and DNV GL with the aim to collect quantifiable evidence to support that the UK distribution network of 2032 will be comparably as safe operating on 100% hydrogen as it currently is on

natural gas. This innovative project begins to fill critical safety evidence gaps surrounding the conversion of the UK gas network to 100% hydrogen. This will facilitate progression towards H21 Phase 2 Operational Safety Demonstrations and the H21 Phase 3 Live Trials to promote customer acceptability and ultimately aid progress towards a government policy decision on heat.

DNV GL and HSE Science Division were engaged to undertake the experimentation testing and QRA update programme of work. DNV GL and HSE Science Division also peer reviewed each other’s programme of work at various stages throughout the project undertaking a challenge and review of the experimental data and results to provide confidence in the conclusions.

A strategic set of tests was designed to cover the range of assets represented across the Great Britain gas distribution networks. The assets used in the testing were mostly recovered from the distribution network as part of the ongoing Iron Mains Risk Reduction Replacement Programme. Controlled testing against a well-defined master testing plan with both natural gas and 100% hydrogen was then undertaken to provide the quantitative evidence to forecast any change to background leakage levels in a 100% hydrogen network.

Key Findings from Phase 1a:

• Of the 215 assets tested 41 of them were found to leak 19 of them provided sufficient data to be able to compare hydrogen and methane leak rates.
• The tests showed that assets that were gas tight on methane were also gas tight on hydrogen. Assets that leaked on hydrogen also leaked
• on methane including repaired assets.
• The ratio of the hydrogen to methane volumetric leak rates varied between 1.1 and 2.2 which is largely consistent with the bounding values expected for laminar and turbulent (or inertial) flow which gave ratios of 1.2 and 2.8 respectively.
• None of the PE assets leaked; cast ductile and spun iron leaked to a similar degree (around 26-29% of all iron assets leaked) and the proportion of leaking steel assets was slightly less (14%).
• Four types of joint were responsible for most of the leaks on joints: screwed lead yarn bolted gland and hook bolts.
• All of the repairs that sealed methane leaks also were effective when tested with hydrogen.

Although the UK has done a great job of decarbonising electricity generation to get to net zero we need to tackle harder-to-decarbonise sectors like heat transport and industry. Decarbonised gas – biogases hydrogen and the deployment of carbon capture usage and storage (CCUS) – can make our manufacturing more sustainable minimise disruption to families and deliver negative emissions.

Developing the capability to produce hydrogen at scale is one of the key challenges in the race to meet the UK’s ambitious net zero targets. Using the East Neuk of Fife - with its abundant on- and offshore renewables resource and well-developed electricity and gas networks – as a test bed we investigated the use of surplus electricity generated by renewables to produce green hydrogen which could then be used to heat homes and businesses carbon-free.

Aims

The study focused on answering a number of important questions around bringing power-to-hydrogen to Fife including:

How much low-cost low-carbon electricity would be available to a power-to-hydrogen operator in Fife and how much hydrogen could be produced today and in 2040? How much hydrogen storage would be required to meet demand under three end-use cases: injection into the natural gas grid; use in a dedicated hydrogen grid for heating; and use as transport fuel for a small fleet of vehicles? What if any network upgrades could be avoided by implementing power-to-hydrogen? Which hydrogen end-use markets would be most attractive for a power-to-hydrogen operator? What are the regulatory legislative or market barriers to be overcome to realise large-scale deployment of power-to-hydrogen?

The study

Our expert researchers used a high-level model of the European electricity system and established wholesale prices generation volumes by generation type and constrained generation in Fife. Considering both the present day and a 2040 picture based on National Grid’s Two Degrees Future Energy Scenarios our team explored a number of configurations of power generation and hydrogen end-use to assess the value associated with producing hydrogen.

Alongside this modelling our team conducted a comprehensive review of power-to-hydrogen legislation and regulation and reports and academic papers to identify the current characteristics and direction of the sector observe where most progress had been made and identify lessons learned.

This report and any attachment is freely available on the ENA Smarter Networks Portal here. IGEM Members can download the report and any attachment directly by clicking on the pdf icon above.

An overview of the HyDeploy project at Keele University where hydrogen is being blended with natural gas to demonstrate the feasibility of using hydrogen to heat our homes.

The natural gas industry proposes carrying out trials on limited parts of the gas network using hydrogen as an alternative to natural gas as a fuel. Ahead of these trials it is important to establish whether the zones of negligible extent that are typically applied to natural gas systems could still be considered zones of negligible extent for hydrogen. The standard IGEM/UP/16 is commonly used by the natural gas industry to carry out area classification for low pressure gas systems for example as found in boiler houses. However IGEM/UP/16 is not applicable to hydrogen. Therefore IGEM commissioned HSE’s Science Division to develop some data that could be used to feed into an area classification assessment for the village trials.<br/>This report identifies two main elements of IGEM/UP/16 which may not apply to hydrogen and suggests values for hydrogen-specific alternatives. These are the ventilation rate requirements to allow a zone to be deemed of negligible extent and the definition of a confined space.

The H21 Phase 2 research will provide vital evidence both towards the hydrogen village trial and potential town scale pilots and to the Government which is aiming to make a decision about the use of hydrogen for home heating by 2026.

The key objectives of the H21 Phase 2 NIC project were to further develop the evidence base supporting conversion of the natural gas distribution network to 100% hydrogen. The key principles of H21 NIC Phase 2 were to:

→ Confirm how we can manage and operate the network safely through an appraisal of existing network equipment procedures and network modelling tools.

→ Validate network operations on a purpose-built below 7 barg network as well as an existing unoccupied buried network and provide a platform to publicise and demonstrate a hydrogen network in action.

→ Develop a combined distribution network and downstream Quantitative Risk Assessment (QRA) for 100% hydrogen by further developing the work undertaken on the H21 Phase 1 QRA and the Hy4Heat ‘downstream of ECV’ QRA.

→ Continue to understand how consumers could be engaged with ahead of a conversion. This programme was split into four phases detailed below:

→ Phase 2a – Appraisal of Network 0-7 bar Operations

→ Phase 2b – Unoccupied Network Trials

→ Phase 2c – Combined QRA

→ Phase 2d – Social Sciences

The project with the support of the HSE’s Science & Research Centre (HSE S&RC) and DNV successfully undertook a programme of work to review the NGN below 7 barg network operating procedures. The project implemented testing and demonstrations on the Phase 2a Microgrid at DNV Spadeadam and Phase 2b Unoccupied Trial site in South Bank on a repurposed NGN network to provide and demonstrate the supporting evidence for the required changes to procedures. Details of the outputs of the HSE S&RC procedure review and the evidence collected by DNV from the testing and demonstration projects is provided in detail in this technical summary report.

Due to the differences in gas characteristics between hydrogen and natural gas changes will be required to some of the operational and maintenance procedures the evidence of which is provided in this report. The Gas Distribution Networks (GDNs) will need to review the findings from this project when implementing the required changes to their operational and maintenance procedures.