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£6.8 million awarded to H21 for second phase of hydrogen network research


About H21

In 2016, Northern Gas Networks, the gas distributer for the North of England, produced the H21 Leeds City Gate feasibility study.

Based on a blueprint of the city of Leeds, this pioneering industry first concluded it was technically possible and economically viable to decarbonise the UK’s gas distribution networks by converting them from natural gas to 100% hydrogen.

Leeds City Gate also demonstrated that this could be achieved at an acceptable cost to the customer.

Before the vision of a hydrogen gas network can be fully realised, the critical safety-based evidence for such a conversion, upstream and downstream of the meter, must be provided. Without it, a credible government policy decision on decarbonisation of heat cannot be made.

On behalf of the UK gas networks (Northern Gas Networks, Cadent, SGN and Wales & West Utilities), a Network Innovation Competition bid was successfully submitted to OFGEM in 2017, as a first step towards providing this evidence.

After securing £9 million Ofgem funding, with a further £1 million contributed by the UK networks, H21 NIC is working to present the quantified safety evidence between natural gas and 100% hydrogen used within the existing GB as distribution networks.


The H21 NIC will be delivered in 2020, followed by field trials. Phase One of the NIC project is being carried out in two parts: 

Phase 1a – Background testing at the Health and Safety Laboratories, Buxton. These tests, on a huge variety of network assets including pipes, valves and joints, will confirm potential changes in background leakage levels.

Phase 1b – Consequence testing at the DNV-GL facility at RAF Spadeadam in Cumbria. This phase will involve tests to confirm any changes to safety risk under background conditions, failure and operational repair on a hydrogen gas network.

Following on from the evidence found in Phase 1a and 1b the project will move forward into Phase 2. Phase 2 will involve testing of operational procedures.

To enable the field trials to commence once Phase 1 is completed the project has secured Network Innovation Allowance funding to locate suitable test sites and develop the conceptual design, now underway. In line with BEIS’ Hy4Heat project, once the field trials have proven that it is safe to move forward there will be a live trial in 2021/2022.


Conversion of the North of England

Underpinning the safety case is the H21 North of England, a strategic report presenting a conceptual design for converting the gas networks of the North of England to hydrogen between 2028 and 2035.

This report builds on the original Leeds City Gate study, as a solution for deep decarbonisation of heat.

This includes 3.7 million meter points (circa 85 TWh per annum, 12.5% of net UK population) across the major urban conurbations of Leeds, Bradford, Wakefield, Huddersfield, Hull, Liverpool, Manchester, Teesside, Tyneside and York. The design incorporates a 12.15GW hydrogen production facility, 8TWh of inter-seasonal storage, all associated onshore infrastructure and the requirements of the associated carbon capture and storage scheme, scaling to 20 million tonnes per annum by 2035.

H21 North of England represents one scenario for hydrogen gas grid conversion, a credible engineering solution following completion of the last pieces of critical safety evidence, which will be provided by the Hy4Heat and H21 NIC programmes by 2023. The H21 programme is supported by a range of strategic Network Innovation Allowance projects, which feed into both the NIC and North of England.

Meet the H21 team

Our dedicated team of experienced industry professionals are delivering a suite of projects providing compelling evidence for a UK gas grid conversion to hydrogen.



  • Tim Harwood

    Tim has 39 years experience in the UK gas industry covering a wide range of operational and project roles across all pressure ranges and assets types within distribution and transmission. Previously working for 8 years in National Grid Transmission (NGT) he held a number of senior roles as pipeline engineer, project delivery engineer and engineering manager. Tim’s previous roles at Northern Gas Networks (NGN) include Head of Captial Projects, Head of Maintenance and Programme Manager Major Projects.

    Tim’s current role is Head of Programme Management at Northern Gas Networks (NGN) with responsibility for the H21 project.

  • Keith Owen

    Keith begin his career with British Gas as Communication Systems Engineer, working on a variety of projects supporting the business communications infrastructure and control centre operations.

    In the following years he undertook a variety of roles within the industry which in 2013 led to the role of Head of Asset Assurance, overseeing the Distribution System Operator function on behalf of Northern Gas Networks.

    In 2016, Keith was appointed Head of Systems Development and Energy Strategy. This new position specifically looks at the role of gas, within the context of the UK energy system, the underpinning infrastructure and the potential benefits a whole systems approach to systems planning and operation can bring, to both the customer and wider UK energy industry.

    Keith is the project manager for InTEGReL, the whole energy systems research and development centre launched in 2017 by NGN, in partnership with Northern Powergrid and Newcastle University.

    He became the Strategic Manager for H21 in 2018.

  • Mark Danter

    A highly experienced chartered engineer, Mark has a proven track record of delivering multi-disciplinary project programmes including water, LPG, bio-diesel, ethanol and white fuels, as well as methane.

    Mark has worked on several innovation and pilot projects within the gas industry and took on the role of Project Director for conversion from LPG to natural gas in Douglas, Isle of Man. Mark is now Senior Project Manager for the H21 suite of projects.

  • Russ Oxley

    Russ has spent his entire career working in the gas distribution industry ensuring major mains replacement, diversion and CAPEX projects are delivered to the highest levels of safety performance, efficiency and customer satisfaction.

    As H21 Phase 1A Project Manager, Russ is is responsible for ensuring that critical safety based leakage evidence is gathered from a programme of strategic tests undertaken at a new purpose built H21 test facility in Buxton Derbyshire. The outcome of these tests will also allow any commercial or operational impact to be considered.

  • Neil Travers

    Neil started his career in the gas industry as an apprentice engineer in 2001 with Transco.

    He spent 12 years as an Emergency Service Engineer and has since worked as Site Manager across several operational work streams including Purge & Relights, Mains Replacement and Repair Activities. More recently he was appointed Operations Manager and has been involved with previous NIA funded innovation projects.

    Neil joined the H21 team in October 2019 as Project Manager/Engineer to oversee delivery of the Phase 2 NIA Field Trials Design project ahead of the Phase 2 NIC project, which is pending funding approval.

  • Lee Crowley

    Lee spent the first part of his carrier serving within the armed forces worldwide . He then joined the gas industry as a Gas Meter Engineer and First Call Operative in 2010, before eventually joining NGN permanently in 2012 working as a First Call Operative attending gas escapes throughout the East Yorkshire coast area.

    In 2015 he joined the mains replacement side of the business (REPEX) in the role of Site Manager and soon became an Authorizing Engineer allowing him to oversee projects of all sizes and pressure ranges within the North Ridings area.

    2018 saw him move across into the Major Projects department, fulfilling the role of Site Supervisor, which involved overseeing main works contractors on projects of all sizes and pressure ranges including high pressure work.

    Lee now works within the H21 team Project Managing Phases 1a and 1b of the NIC project.

  • Al Cargill

    Al Cargill is the senior network analyst on the H21 North of England project with responsibility for modelling of the hydrogen transmission system and the integrity of and conversion strategy for the West Yorkshire distribution network.

    In addition, he supported the UK GDNs in developing the hydrogen conversion modelling in their businesses. Al joined the H21 team at the start of the Leeds City Gate project in 2016. Before this, he worked as an NGN network analyst for 15 years, designing reinforcement and REPEX projects for large diameter mains.

  • Rob Holden

    Rob has over 20 years’ commercial experience in the civil engineering and construction industry, working for both clients and contractors in the water and gas sectors.

    He joined NGN in 2016 as part of the Major Projects team and oversaw the delivery of a variety of network upgrade projects from the commercial side. Starting with procurement of the design contractors all the way through to the signing off of the successful build contractors final account. The role was all about managing the delivery partners and protecting NGNs interests commercially along with managing the budget allocated for the projects. His portfolio of projects included upgrades of above ground installations, updating of assets with the latest technology in terms of mechanical and electrical installations, and general civils improvements. He was also heavily involved in the upgrading of the overcrossings (pipelines that cross canals, railways and the like).

    Rob recently re-joined the H21 team in August 2019, after originally assisting with the drafting of agreements between the various parties at the outset of the project. He is now responsible for the commercial aspects on the full range of projects being carried out as part of the H21 project.

  • Keith Thompson

    Keith started working in the gas industry in the role of Gas Operative for Transco back in 2000. Throughout his career he has undertaken various roles including Team Leader from 2001 and Network Officer/Site Manager within the Leeds area in 2011.

    During 2013 and 2014 he project managed two innovation trials (acoustic camera and core and vac).

    In March 2018 he joined the H21 team as H21 Project Supervisor and manages the collection of assets from our network for testing at our Phase 1a Test Site located at the Health & Safety Laboratories in Buxton.

  • Richie Dawson

    Richie started working within the gas industry in 1990 as a Distribution Apprentice. Since then his career has involved a wide range of roles and responsibilities within downstream gas. These include working within the Repair, Replacement, Connections, Emergency and Major Projects departments.

    Richie joined the H21 team in 2019 as Project Supervisor of the Phase 1a test site located at Buxton.

  • Stella Matthews

    Stella has had a varied career that has seen her undertake many professional roles, the vast majority of these have been within the heritage sector. She previously set-up and developed a social enterprise that provided training and education through heritage based experiences. In addition to this she has worked as a tutor for the University of Hull and within the adult community education sector, completed a traineeship with the National Archives and undertaken roles at Pricewaterhouse Coopers and the NSW Ombudsman.

    Stella has worked within the gas industry for the past two years, undertaking roles at Northern Gas Networks. Her current role is as Project Officer on the H21 suite of projects.

Project Partners


Northern Gas Networks

Northern Gas Networks (NGN) is the gas distributer for the North East, most of Yorkshire and northern Cumbria, transporting gas to 2.7 million homes and businesses.NGN’s network consists of 37,000 km of gas mains, enough to stretch from Leeds to Sydney, Australia and back. The business generates £300 million each year for the region’s economy by stimulating employment and consumer spending.

NGN’s mains replacement programme will see 3,800 km of old metal gas main replaced with modern plastic equivalents by 2021, with work carried out by local contractors to ensure that investment stays in our region. The distributer is championing gas as a clean, renewable and cost effective energy source and actively exploring how the network can be adapted to transport alternative forms of gas, keeping infrastructure costs and customer bills down.



Cadent owns, operates and maintains the largest gas distribution network in the UK, safely transporting gas safely to 11 million homes and businesses across West Midlands, North West England, East of England and North London.



SGN is the gas distributer managing the network that safely distributes natural and green gas to 5.9 million homes and businesses across Scotland and the south of England, operating more than 71,000 km of pipes


Wales & West Utilities

Operating the gas distribution networks across Wales and the South West of England, WWU look after 7.5 million domestic and business customers, safely transporting gas across 35,000 km of pipes.


Health & Safety Laboratories

HSL is a world-leading provider of health and safety solutions to industry and government. Combining scientific, medical and technical expertise, the HSL manages risk and protects the workforce from illness and injury.



DNV GL is a global quality assurance and risk management company, providing classification, technical assurance, software and independent expert advisory services to the maritime, oil & gas, power and renewables industries. Its large-scale Spadeadam Testing and Research centre delivers unique multiphase flow testing facilities, harnessing technologies and expertise required to investigate and address customers’ most challenging technical needs.