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Projects: Projects for Investigator
Reference Number NIA2_SGN0019
Title Retrofit Excess Flow Valves (EFVs)
Status Completed
Energy Categories Hydrogen and Fuel Cells(Hydrogen, Other infrastructure and systems R&D) 100%;
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
SGN - Scotland
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 May 2022
End Date 28 February 2023
Duration ENA months
Total Grant Value £226,660
Industrial Sectors Energy
Region Scotland
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , SGN - Scotland (99.999%)
  Other Investigator Project Contact , SGN - Southern England (0.001%)
  Industrial Collaborator Project Contact , SGN (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA2_SGN0019
Objectives The project will be split in 3 main phases, outlined below: Phase 1 – EFV lab testing programme (Kiwa) Agree the products and installation options to be tested. Source a sample of a minimum of 3 models of EFV for testing. Construct the test rig to accommodate the EFVs procured. Undertake the test programme using hydrogen considering the following: -Vary supply pressures from 25 to 75 mbar to represent the low pressure (LP) distribution range.Measure the pressure drop across the EFV against the flow rate.Record the flow rate at which the EFV operates to isolate the flow.Record the flow rate of hydrogen through the EFV bypass orifice.Fully close the gas supply using isolation valve and allow EFV to reset.Re-open isolation valve and record the volume of gas released before EFV isolates flow. Review the results and how they compare with the requirements of the hydrogen EFV standard IGEM/H/PRS/1. Prepare a draft report explaining the results for discussion prior to producing a final report. Draft a letter to IGEM to advise them of any updates required to the hydrogen EFV standard to improve its applicability to reducing risk.Phase 2 – Gas escape modelling (Kiwa) Consider the concentration of gas reached at steady state following releases into representative rooms. Consider the effect of the real operating points of EFVs as well as the EFV functionality included in hydrogen smart meters.Phase 3 – EFV Tooling and Techniques (Synthotech) Market review and industry consultation of available EFVs and appropriate tools/techniques for insertion into PE service pipe. Develop tests for chosen products and undertake required testing programme. Review the findings and prepare a report. Develop a new or adapt an existing retrofit EFV, technique and tooling for use with hydrogen.Measurement Quality StatementThe main approach of the project will be to identify and test EFV products currently available on the commercial market for use with 100% hydrogen. A test rig representative of a gas service pipe will be constructed by our contracting partner to undertake a suite of tests to confirm the suitability or otherwise of a number of sample EFVs. This is important as it will allow SGN to demonstrate the suitability and operability of this key safety feature.Data Quality StatementRegular meetings will be held with key stakeholders from each network and the suppliers to agree the format for the sharing and storage of project data. Kiwa and Synthotechs involvement in the project will ensure a consistent approach in the presentation of the evidence and data due to their involvement in previous EFV projects and their knowledge of insertion techniques for PE services. The scope of work involves identifying a selection of a minimum of 3 no. sample EFVs from existing products available on the commercial market. In the first phase this will concentrate on EFVs that are either installed as electrofusion fittings in the PE service or after the ECV as a mechanically-threaded fitting. Phase 3 will focus on EFVs that can be inserted into the PE service pipe. In order to test their effectiveness with 100% hydrogen, a bespoke test rig will be constructed complete with PE service pipe, an ECV and an EFV with a flow meter for measuring gas flow, pressure sensors for measuring differential pressures and a needle valve for setting the flow. Undertake a testing programme using 100% hydrogen to demonstrate the effectiveness of the various samples of EFV.The second phase ofthe project will involve a series of gas escape modelling using the two-vent model of gas dispersion to consider the concentration of gas reached at steady state following releases into theoretical rooms representing four combinations of room volume and air tightness. This will also consider the effect of real operating points of EFVs as well as the EFV functionality included in the hydrogen smart meters. The main objectives of the project are to certify a number of EFVs for use with 100% hydrogen for both trials and eventual adoption for the entire gas network post conversion. The idea will be to scope an electrofusion fitting, a mechanically threaded fitting and, if possible, an EFV for insertion into an existing service pipe.This will allow the H100 Fife trial and all future village trials to proceed incorporating this key safety feature and meeting the requirements of the QRA.
Abstract The project will look to procure and test a number of excess flow valves (EFVs) and determine their suitability for use with 100% hydrogen networks. To comply with the Hy4Heat QRA there is a requirement to install an EFV in every hydrogen service either within the service pipe or immediately after the ECV. For new service installations as part of the H100 neighbourhood trial, the EFV will be installed at the junction of the service pipe and the main at the outlet of the tapping tee as an electrofusion fitting. This project will also look at other options for installing the EFVs including after the emergency control valve (ECV) as a mechanical threaded fitting and inserted into the service pipe using a catheter-type tooling technique.
Publications (none)
Final Report (none)
Added to Database 14/10/22