Projects

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.

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

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.

This project proposes a structured approach to assess the integrity of AGI pipework for hydrogen service. It includes development of a screening tool based on representative AGI archetypes execution of ECAs to define flaw tolerances and inspection intervals and evaluation of NDT capabilities with respect to desired AGI performances. The project also reviews integrity management software to support increased digitalisation and monitors emerging technologies for hydrogen-related NDT developments.

The study will identify the significant technical fiscal and political challenges current heat decarbonisation strategy faces and outline an alternative approach involving greater use of hybrid devices that offers both lower consumer costs and greater potential to cut carbon emissions than projected based on current policy and consumer behaviour. Arguments will be presented through four linked pieces of analysis:

1. An examination of the costs of the Government’s Clean Heat Market Mechanism (a key policy intervention to promote heat pumps in the appliance market).
2. An approximation of the additional network upgrade requirement early transfers to heat pumps represent in comparison to hybrids.
3. A view on what extending the Green Gas Levy beyond its current cut-off date could do to the emissions intensity of the gas distribution network (by encouraging more biomethane production).
4. Voter polling that analyses their view on different approaches to heat decarbonisation.

The paper will include a series of policy recommendations for government to take forward in order to enhance progress on decarbonisation of domestic heat.

UK gas networks are managed and maintained using an extensive suite of policies policies standards and procedures. These documents have been developed gradually over decades of gas network operation however the transition to hydrogen necessitates a wholesale review and update of all existing documents. There is much commonality between the networks’ documents and therefore it would be most efficient to update these documents in a coordinated way to avoid the unnecessary duplication of effort.