The UK, as with most other countries around the world, recognises the challenge of climate change. It has committed to reduce carbon emissions by 80% of their 1990 level by 2050. In the UK, this is a legal obligation defined under the terms of the UK Climate Change Act 2008. Climate change is one of the most significant technical, economic, social and business challenges facing the world today. To date, there has been little investigation into the opportunity to decarbonise the GB gas distribution networks at a scale commensurate with climate change targets.
Currently the UK requires circa 1,500 terawatt hours (TWh) of energy to support heat, transport and electric generation. Around 83 TWh (Digest of UK Energy Statistics 2016) of this energy comes from renewable sources. This is 5% of net energy demand i.e. 25% of the red line on the graph. Almost half of the energy consumed in the UK is to provide heat (760 TWh). That is more than that used to produce electricity or for transport. Around 57% of this heat (434 TWh) goes towards meeting the space and water heating requirements of our homes (Ofgem Future Insights series: The Decarbonisation of Heat (2016)). Great Britain has a world class gas grid which heats 83% of its buildings as well as providing almost all commercial and industrial heat.
The existing gas grid is well proven in provision of energy through a secure network which is unaffected by weather. The network is designed to meet the energy demand for weather conditions occurring once every 20 years, i.e. exceptionally cold requiring all appliances etc. are on. If the gas network can be repurposed to transport a low/zero carbon gas it will allow the UK to capitalise on paid for existing assets (the gas grid) whilst ensuring customers do not require disruptive and expensive changes in their homes versus alternative low carbon solutions. Furthermore, providing a long-term solution to climate change which utilises both the gas networks and electricity networks presents customers of tomorrow with the same choice and security as customers of today, gas or electricity. As a collective community, we need to fully appreciate the size of the challenge to replace the energy provided currently by natural gas with a compatible low carbon gas alternative or equivalent energy by electricity.
Bio gases, i.e. gases developed from a biological feedstock (such as bio-methane) can support decarbonisation of the gas grid in the context of short term carbon budgets. However, whilst important contributors, they will always be limited by feedstock availability and competition for the ‘bio’ feedstock from the transport and electric sectors. Optimistically, bio feedstock may be able to supply up to 10% of net UK energy. This would be an incredible achievement at circa 150 TWh. However it falls significantly short of the energy required to decarbonise the entire UK gas network in the context of the 2050 challenge. Alongside international energy trading (see later in this piece), this is the primary reason a conversion of UK gas networks to 100% hydrogen is proposed as a credible option to meet the climate change challenge.
The Original H21 Leeds City Gate Project
When designing the H21 Project we wanted to consider if there was a gas which could be used to decarbonise the gas networks in the context of the climate change obligations. The current GB gas distribution network transports natural gas (predominantly methane, CH4) which is then burnt in customers’ properties across the country producing carbon dioxide, water and heat. Hydrogen (H2) when burnt only produces water and heat. A conversion of the GB gas distribution networks (GDNs) to hydrogen would provide customers with all the benefits of gas and the gas networks without the carbon footprint.
In July 2016, the H21 Leeds City Gate report was released. The report confirmed that the conversion of the UK gas network to 100% hydrogen was both technically possible and economically viable. The report provided evidence that the UK gas networks are the correct capacity to be converted to 100% hydrogen, low carbon hydrogen could be credibly sourced at scale, conversion of UK cities could be achieved incrementally, appliances could be converted to operate on 100% hydrogen, and hydrogen could be stored to manage intraday and inter-seasonal swings in demand. Additionally, the report provided a financing methodology which would keep the impact on UK customers’ bills to a minimum taking advantage of the natural expenditure profile of the UK gas industry and its established financing methodology. All the full details can be found in the H21 report available via the Northern Gas Networks website1but the headline design parameters for one city (Leeds) are:
• Hydrogen would be provided through a production capacity of 1,025 MW via 4 off 256 MW Steam Methane Reformers (SMRs) located at Teesside due to its access to Carbon Capture and Storage (CCS)
• Total annual demand (in a peak year) would be 6.4 TWh
• Intraday storage of circa 4,000 MWh will be provided via salt caverns in the Teesside region
• Inter-seasonal storage of 700,000 MWh will be provided via salt caverns in the Humber region
• 5m tonnes of CO2would be sequestered per annum.
• The total costs to convert Leeds including hydrogen production and storage, all associated infrastructure and appliance conversions would be circa £2bn
Since release of the H21 LCG report there have been numerous publications acknowledging the potential of a 100% hydrogen gas grid conversion and calling for urgent action to provide the outstanding pieces of critical evidence. Most notable of these is the independent body ‘The Committee on Climate Change’ (CCC) and their October 2016 publication ‘Next Steps for UK heat policy’. This was followed in October 2017 by the UK Governments ‘Clean Growth Plan’ which shows a 100% hydrogen conversion as one of the large scale credible options for decarbonisation.
H21 – What’s Happening Now
A conversion of the UK gas networks to hydrogen is technically achievable. The key outstanding evidence required to allow a policy decision on conversion is the quantified safety based evidence that a 100% hydrogen gas grid represents a comparable risk to the current natural gas grid and/or a towns gas grid. Two significant pieces of work are now underway which aim to provide this evidence by 2021.
Firstly, the £25m ‘Downstream of the Meter’ Programme lead by the UK governments Department of Business Energy and Industrial Strategy (BEIS). Throughout 2016 Dan Sadler was seconded to BEIS in the role of ‘Technical Advisor – Future of the Gas Networks’. A primary element of the role involved working with the relevant policy teams (specifically heat and science) to help define a BEIS programme which would focus on de-risking 100% hydrogen within their allocated budget constraints.
This programme will provide the quantified safety based evidence within buildings as well as providing capital stimulus to the appliance sector to produce a range of 100% hydrogen compatible appliances and burners.
Secondly, the £10.3m ‘H21 – NIC’ Programme lead by Northern Gas Networks in conjunction with all the GDNs of Great Britain (Cadent, Scottish and Southern Gas Networks, Wales and West Utilities) and awarded funding by Ofgem in November 2017. The H21 NIC project is designed to complement the BEIS programme and focuses on providing the safety based evidence for 100% hydrogen conversion ‘Upstream of the Meter’, i.e. on the GB GDNs network assets. These complementary but fundamentally different programmes will collectively provide the critical safety based evidence required to progress towards a policy decision.
In addition to these two programmes a growing number of strategic H21 projects are also underway. As with the H21 NIC project this are all being managed out of the H21 office near Leeds and include:
• H21 – Alternative hydrogen production and storage methodologies. Developed in conjunction with Statoil and Cadent, this project is due for release in late 2018 and builds on the original ‘H21 – Leeds City Gate’. The project will present a ‘conceptual design’ for converting the North of England. This includes three million meter points (circa 85 TWh per annum) including the areas of Hull, Liverpool, Manchester, Teesside, Tyneside, West Yorkshire, York. The design includes alternative methods of large scale production, inter-seasonal storage considerations using a combination of salt caverns and ammonia, all associated onshore infrastructure and the requirements of the associated CCS scheme. This project could present a credible ‘first policy’ option for UK government
• H21 – Strategic Modelling Major Urban Centres
• H21 – Domestic Metering
• H21 – Keighley and Spadeadam Designs
• H21 – Field Trials Design
The H21 project has captured the imagination of the energy supply chain with a significant increase in hydrogen based projects across the energy sector and its supply chain. A notable example is Worchester Bosch who, on Monday 11th December, commissioned their 100% hydrogen boiler prototype confirming the appliance ran ‘very well’.
International Momentum and the H21 Vision
The global community all have the same climate change commitments and the growing recognition of the difficulty as to how to meet such an incredible challenge. Big problems need big solutions and the H21 concept has the potential to be the single biggest contributor to meeting global climate change obligations and as such is gathering an international momentum. H21 interest is growing and H21 based studies are under development in Australia, China, Europe, Ireland, Japan, Hong Kong, Scotland and New Zealand. There is strong and growing local support across many of the Northern local authorities (West Yorkshire, Liverpool, Manchester, Teesside, Newcastle) recognising the benefits to air quality, job creation and climate change targets.
Finally, the H21 project team believe that a conversion to 100% hydrogen in the UK gas grid would allow the UK to meet its clean energy targets by 2050 whilst facilitating a realistic, longer-term, transition to entirely green energy. This longer-term vision would utilise hydrogen to balance global renewable energy requirements with places with excess, for example Australia, a continent with 24 million people, trading green energy with places with shortages, for example the UK with 66 million people. The graph below demonstrates how this transition may occur up to 2100 and, whilst illustrative, is based on credible timescales and delivery for truly large scale domestic and global hydrogen economies.
The H21 concept is to convert the UK gas distribution network to 100% hydrogen over time thereby decarbonising heat and supporting decarbonisation of electric, large industrials and transport. This would be achieved using technology available across the world today whilst maintaining the benefits of gas and the gas networks in the energy mix for the long-term future. If undertaken such a conversion would represent the single biggest contribution to meeting climate change obligations.
We need to be clear that a 100% hydrogen conversion does not negate the need for other measures, i.e. energy efficiency improvements, increasing renewables, some nuclear, district heating, ‘bio’-energy etc. However, whilst there is a common ‘no silver bullet’ consensus, we need to be collectively realistic and recognise different ‘bullets’ have very different contribution capabilities when considered against the 2050 targets. Furthermore, we also need to remember that 2050 is only over 30 years away and large energy infrastructure construction takes time. Deployment timescales of different ‘bullets’ are often not realistically considered instead preferring economic analysis over credible deliverable actions.
The H21 project represents an opportunity to do something fundamental and for the UK to lead the world in large scale decarbonisation strategies. With continued national, local and international support we can gather the remaining pieces of evidence to make this a reality.