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Projects: Projects for Investigator
Reference Number NIA_CAD0079
Title FI-0011 - Functional Specification: Hydrogen Blending Infrastructure
Status Completed
Energy Categories Fossil Fuels: Oil Gas and Coal(Oil and Gas, Refining, transport and storage of oil and gas) 50%;
Hydrogen and Fuel Cells(Hydrogen, Other infrastructure and systems R&D) 50%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
Cadent Central
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 May 2022
End Date 30 November 2022
Duration ENA months
Total Grant Value £160,366
Industrial Sectors Energy
Region West Midlands
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , Cadent Central (99.991%)
  Other Investigator Project Contact , Wales and West Utilities (0.001%)
Project Contact , National Grid Gas Transmission (0.001%)
Project Contact , Cadent Eastern (0.001%)
Project Contact , Cadent North London (0.001%)
Project Contact , Cadent North West (0.001%)
Project Contact , Cadent West Midlands (0.001%)
Project Contact , Northern Gas Network (NGN) North East (0.001%)
Project Contact , SGN - Scotland (0.001%)
Project Contact , SGN - Southern England (0.001%)
  Industrial Collaborator Project Contact , Wales and West Utilities (0.000%)
Project Contact , Northern Gas Networks (0.000%)
Project Contact , Cadent Gas (0.000%)
Project Contact , SGN (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA_CAD0079
Objectives Work Pack 1 – Functional specification A generic functional specification will be developed that will set out the functionality requirements for the hydrogen-to-grid blending facility. Appendix A provides an indicative structure for the functional specification. The structure is based on the Functional Specification produced for biomethane-to-grid facilities by Dave Lander Consulting Limited on behalf of the Review Group on Energy Market Issues for Biomethane Projects (EMIB). The two facilities (biomethane-to-grid and hydrogen-to-grid) will share many common features. However, it is likely that some of the unique features of hydrogen will necessitate amendment as evidence gathering and assessment progresses.In order to develop these functionality requirements several key principles will need to be established. These principles will dictate the direction of travel in establishment of the functional specification and are discussed in the following sections.Key Principle 1 – The legislative and regulatory frameworkThe most relevant items of legislation with respect to blending of hydrogen into the natural gas network are the Gas Safety (Management) Regulations (GSMR) and the Gas (Calculation of Thermal Energy) Regulations (GCOTER). Schedule 3 of the GSMR requires gas transporters to not convey gas that contains more than 0.1% hydrogen, so in order to blend hydrogen in significant quantities a future amendment to the GSMR is required. The Network Innovation Competition project HyDeploy aims to demonstrate the safe conveyance and utilisation of a blend of up to 20% hydrogen in natural gas and is likely to provide the principal evidence base for such an amendment. HyDeploy is currently conducting a field trial of blending in a small part of Northern Gas Networks medium pressure system in Winlaton near Newcastle, having previously successfully conducted a field trial in a private network at Keele University. The two field trials are being conducted under formal exemptions from the GSMRs hydrogen requirements and a third phase of HyDeploy is addressing demonstration of safety of the wider roll-out within GB of hydrogen blending.The GCOTER specify the basis by which consumers are billed for gas they consume and place certain limits on the calorific value (CV) employed to derive gas users energy bills. The principal driver is that the daily billing CV for a charging area cannot be more than 1 MJ/m3 greater than the CV of the lowest source of supply into that charging area. Compared to natural gas, hydrogen has a low calorific value and hence blends of hydrogen with natural gas could become the lowest source and trigger a cap in the billing CV.The triggering of caps in billing CV can have significant financial consequences in terms of unbilled energy. However, the Hydrogen Blending Feasibility Study set out conditions by which hydrogen could be blended without triggering a cap in billing CV and indicates the key operational features in terms of the percentage hydrogen added to natural gas and the proportion of total energy delivered each day into a charging area as blend.Task 1: We propose to build on the conclusions of the Hydrogen Blending Feasibility Study by further discussion with Gas Transporters and Regulators on the constraints, and agreement of the functionality that will deliver the means to control hydrogen percentage in natural gas both locally and in co-ordination across multiple sites to ensure the risk of billing CV capping is mitigated. The regulatory basis by which hydrogen can be permitted will be set out in the functional specification.End user requirementsBased on the lessons of HyDeploy to date, we expect that most consumers appliances, such as domestic and commercial users, will be largely unaffected by the conveyance of hydrogen blend. However, we recognise that some users – particularly process users of gas – may experience some sensitivity to hydrogen, and in particular, rapidly-changing gas properties as a result of variation in hydrogen. Some industries are sensitive specifically to hydrogen – gas engines are sensitive to engine “knocking” and are particularly sensitive to hydrogen – whereas others are not sensitive to hydrogen per se, but to properties that change when hydrogen is added – the Wobbe index of the blend, for instance.HyDeploy is consulting with commercial and industrial users on this issue, and we expect that valuable insight will be available from HyDeploy into end-user sensitivities so that properties of blend leaving the blending facility are controlled in a manner that is appropriate to the needs of those sensitive users. We do point out that gas quality variation – and in particular rate of change of gas quality – will also occur at the interface between blend and natural gas within the gas network. As supply and demand patterns change the “zone of influence” of a hydrogen blend supply will enlarge and contract and it is likely that some users may experience rapid transitions between blend and natural gas. Mitigation of transitions in gas quality is not simply a case of ensuring good control of hydrogen concentration at the blending facility. Other mitigation strategies will need to be pursued, such as identification of sensitive users within the likely zone of influence and assessment of local mitigation measures.Task 2: We propose to establish the most effective blending control strategy by consultation via a one-day workshop with key parties, including end-users and HyDeploy project staff to establish the likely limitations in gas quality for sensitive users, the most appropriate gas quality strategy at the blending facility, and identification of the most sensitive users for whom local mitigation measures may be required. Hydrogen Supply profilesCurrently there is a limited hydrogen production and supply infrastructure in GB and extended roll-out of hydrogen blending in gas networks will require a co-ordinated approach with other projects to ensure that as production capability becomes available, stakeholders can be confident that hydrogen blending into the gas network is both a feasible and cost-effective use of hydrogen. The operational constraints to control capping of billing CV will drive towards balancing availability of hydrogen with the necessary proportion of hydrogen in blend and the necessary proportion of charging area energy supplied as blend.Task 3: We propose to illustrate to stakeholders how growth in hydrogen injection will be dependent on the number and size of hydrogen blending facilities and their location. A number of differing growth scenarios will be presented that will establish hydrogen requirements that can be matched to likely future hydrogen production capability. Operational requirementsThe Hydrogen Blending Feasibility Study has already indicated that successful management of capping of billing CV under the present legislative framework is possible, but that an increased level of management of energy flows across the charging area will be required. We expect that improved network control tools will be essential to within-day management of billing CV capping and in turn such tools will need key information provided “live” from blending facilities.Currently blending and enrichment of biomethane is managed on a local level by assignment of a target CV to the biomethane delivery facility operator. For hydrogen blending a similar approach is envisaged, but the setting of targets may need to be more co-ordinated across the whole of the charging area. A key finding of the Hydrogen Blending Feasibility Study was that conveyance of a blend containing a hydrogen concentration of around 4.7% is unlikely to trigger a cap in billing CV. However, uncoordinated blending of hydrogen at multiple sites on the same pipeline could result in “double-blending” and lead to billing CV capping.Task 4: We propose to illustrate to stakeholders the key site information that will need to be transmitted to and from hydrogen blending facilities to mitigate risk of billing CV capping. Hydrogen storageThe instantaneous hydrogen flowrate required at the blending facility will be dictated by the operating mode appropriate after considering the blending constraints set out in Section 3.1.1 and the end-user constraints set out in Section 3.1.2.Task 5: We propose construction of a model of hydrogen supply and hydrogen demand at the blending facility that will estimate the appropriate hydrogen storage requirement. We anticipate that two hydrogen storage options will need to be assessed: on-site storage vessels and linepack in the hydrogen supply pipeline. Advantages and disadvantages of both options will be assessed and a recommendation on situations where one or a combination of both elements might be considered. Other Gas Quality requirementsHydrogen content and calorific value are not the sole gas quality parameters that will need to be controlled at the blending facility. Schedule 3 of the GSMR sets out additional requirements, such as:- Hydrocarbon and water dew temperature- Carbon dioxide content- Wobbe index and the interchangeability parameters Incomplete Combustion Factor and Sooting Index- Odour Intensity and odour characterIn general, the blending of hydrogen will reduce the risk of impact of most of these parameters except for Wobbe index and odorisation. However, monitoring for low Wobbe index will be required. Adding unodorised hydrogen will lower the odour intensity of the blend and the strategy for dealing with this will depend on the location of the blending facility. In essence, independent blending facilities will need an independent odorant injection facility, whereas blending facilities located at NTS offtakes, for instance, can utilise existing odorisation injection equipment provided the control strategy is adapted. The lower flammability limit of blend is slightly different from natural gases. This will require a slightly different odorant injection rate from natural gases, but this is very small, and the functional correction will set out the appropriate correction to apply for blends.Task 6: We propose to set out and evidence in the functional specification other gas quality parameters that will need to be monitored and/or controlled. Other Key Functionality requirementsHydrogen blending will require utilisation of technology not commonly applied at natural gas AGIs and we propose to include an assessment of two key technologies:- Hydrogen sensing and measurement. Hydrogen sensing and measurement will be required for blend control as well as for determination of CV and other gas properties.- Gas mixing. Demonstration of optimum mixing of hydrogen with the blending natural gas is important for billing purposes that CV determined at the mixing point is representative of the blend. In addition, space may be at a premium at some AGIs so selection of the most efficient and compact mixing equipment will be crucial. Good mixing has been demonstrated in the HyDeploy field trial at Winlaton, but for confident extension to the high pressures of mixing at LTS pressures, we propose that demonstration of mixer performance using computational fluid dynamics of the preferred option be carried out in the Case Study.The functional specification will set out functional safety requirements.The functional specification will assess the accuracy requirements demanded for CV and volume determination for billing CV purposes and also monitoring arrangements for compliance with the requirements of the GSMR.Task 7: We propose to set out and evidence in the functional specification the remaining key functionality requirements that will need to be incorporated in the design of the hydrogen blending facility. Work Pack 2 – CASE StudyThe feasibility of the functional specification from Work Package 1 will be tested by development of a high-level design and cost estimate for a hydrogen-to-grid blending facility. The selection of the Case Study will be carried out after detailed discussion with stakeholders after consideration of what might constitute a representative site, availability of information on the site (including site layout and design drawings) and accessibility for site visit(s) to establish any relevant geographical or operational features.Case Study Selection and Site AssessmentThe functional specification will be tested by its application to an appropriate example that is as realistic and appropriate as feasible. The findings of the Hydrogen Blending Feasibility Study indicate that location at the highest-pressure tier (e.g., injection into a Local Transmission System), where demand is relatively high, will allow greatest scope for growth of hydrogen as and when initial supplies of hydrogen emerge. Initial hydrogen content in early blending operations is likely to be relatively low (ca. 3.7%), but the high-level design will need to demonstrate that the functional specification is appropriate for higher hydrogen concentrations and flows. Other factors that will impact on site selection include:- Proximity to potential hydrogen supplies, such as those planned within the HyNet project- Existing or greenfield site. If the example blending facility is based on an existing site, such as an NTS offtake, the geography and site size and layout will be known and existing drawings showing existing equipment can be utilised.Task 1: We propose to select the most appropriate example site by consultation via a one-day workshop with Gas Distribution Networks. High Level DesignTesting the output of Work Pack 1 will be essential to ensure that the theoretical can be practically delivered using current technology. We propose to deliver two high level designs that can be reviewed by the stakeholders early in the design phase, selecting one that can be developed fully in line with the project requirements to produce a solution that will meet the legal, regulatoryand network requirements employing BATNEEC.Following selection of the most appropriate design solution to develop, we will devise a basis of design which details the user requirements for both the inlet and outlet conditions as well as the design constraints.The concept design solution will be tailored to the proposed site to verify that the design fulfils the requirements for blending and operation, this will validate how viable the proposition is terms of manufacture and installation but also considering ongoing activities to support the integrity of the system.Within the design phase we will produce a cause-and-effect diagram which will form part of the design pack submitted.  The core aim of this project is to develop a functional specification for the network infrastructure required to successfully deliver hydrogen blending from Industrial Clusters. This will not include hydrogen production or transportation of hydrogen to the blending facility but will consider any need for upstream hydrogen storage.This project is not seeking to produce core technical evidence on the safety of Hydrogen blending, as this is being delivered by projects such as Hydeploy and Future Grid.This project will not explore the commercial frameworks to enable hydrogen blending but will interact with sister project “Functional Specification: Hydrogen Blending Commercial Frameworks”. A case study will be developed in Work Pack 2 to act as a test case of the functional specification and to produce a high-level design, which can be used to derive a high-level cost estimate.The benefits of this project will provide a better understanding of what is physically needed to deploy hydrogen blending into the gas networks, supporting a value-for-money assessment due to be undertaken by BEIS in Q3 2022, and a policy decision in 2023.  The objectives of this project are as follows: 1. Determine the functional requirements of a blending facility2. Understand the infrastructure and equipment needed 3. Assessment of technology and equipment to achieve the functional requirements 4. Assessment of reflective site/s to understand space considerations 5. Understanding of indicative costs to design and build a hydrogen blending facility 6. Highlight any limitations or considerations
Abstract Hydrogen is a key energy source for the Net Zero transition and is being considered as an alternative to natural gas. Over the next 5 years there is an ambitious work plan within the UKs GT and distribution industry to prove the viability of blending hydrogen into the UKs existing gas networks.This project seeks to develop a functional specification for the infrastructure required to blend hydroge from industrial clusters.Separate projects will explore the adaptations necessary to commercial frameworks and in other blending scenarios
Publications (none)
Final Report (none)
Added to Database 14/10/22