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Projects: Projects for Investigator
Reference Number NIA2_NGET0016
Title Novel methods for sealing SF6 leaks 
Status Started
Energy Categories Other Power and Storage Technologies(Electricity transmission and distribution) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
National Grid Electricity Transmission
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 June 2022
End Date 30 September 2024
Duration ENA months
Total Grant Value £1,100,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid Electricity Transmission (100.000%)
  Industrial Collaborator Project Contact , Scottish and Southern Energy plc (0.000%)
Project Contact , SP Energy Networks (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA2_NGET0016
Objectives Two different technologies will be investigated but there are three elements to the project. Use of metal alloys for leak sealing has been studied for feasibility already as part of the NIC OSEAIT (“Deeside”) project and has been shown to have the potential to be useful for this purpose. The first piece of work will be to demonstrate through dielectric testing of SF6 that there is no metal particle ingress inside the equipment as a result of applying the seal under pressure.On completion of this first study a design will be developed for the mould to be used for sealing leaks. Currently a different mould is required for each application adding time and cost to any SF6 leak that is to be addressed. A modular design is to be developed that will be suitable for all eventualities of SF6 leaks from small bore pipe work. The graphene-based elastomer development for both tape and spray applications will be developed as a third workstream. As part of this project all of the resulting leak seal solutions will be demonstrated on equipment either as pilot projects on a substation, or as a trial in the laboratory or at the Deeside Centre for Innovation on full size equipment.Data Quality Statement (DQS):The project will be delivered under the NIA framework in line with OFGEM, ENA and NGGT / NGET internal policy. Data produced as part of this project will be subject to quality assurance to ensure that the information produced with each deliverable is accurate to the best of our knowledge and sources of information are appropriately documented. All deliverables and project outputs will be stored on our internal Sharepoint platform ensuring access control, backup and version management. Relevant project documentation and reports will also be made available on the ENA Smarter Networks Portal and dissemination material will be shared with the relevant stakeholders. Measurement Quality Statement (MQS): The methodology used in this project will be subject to our suppliers own quality assurance regime. Quality assurance processes and the source of data, measurement processes and equipment as well as data processing will be clearly documented and verifiable. The measurements, designs and economic assessments will also be clearly documented in the relevant deliverables and final project report and will be made available for review.Risk AssessmentTRL Steps = 2 (Lowest TRL for the project is 3 and Highest on completion is 8, however lowest and highest apply to different technologies. Metal alloy solution will increase from 4 to 8 and graphene solution from 3 to 6)Cost = 3 (£1.1m)Suppliers = 2 (3 suppliers) Data Assumption = 1 (Low risk)Assessed risk score 8 - Medium Equipment that contains SF6 can develop leaks over time resulting in loss of SF6 to the atmosphere. SF6 emissions have an impact on global warming over a period of thousands of years because it is very stable as well as having the highest known GWP. The scope of this project is to develop methods for the elimination or significant reduction of SF6 emissions from transmission equipment. The two methods being developed address leaks from different types of equipment. The intention is to be able to apply the seal on energised equipment with as little pre-work, including surface preparation, as possible.  The objective of the project is to develop and evaluate two techniques for the purposes of addressing SF6 leaks in HV substations. During the project sufficient data will be collected to understand how well leaks are ameliorated and they will be demonstrated on HV equipment in substations or a substation-like environment such as at the Deeside Centre for Innovation. 
Abstract This project is aimed at developing two novel methods for sealing SF6 leaks from equipment that are currently difficult to address with available solutions. The intention is that these solutions will be designed to be flexible in terms of the leaks they can stop or significantly reduce, they should be easy to apply and readily removable if necessary.The two solutions are a low melting point metal alloy cast with a modular design of mould for small bore pipe work and a graphene impregnated elastomer which may be applied as a tape and in a spray to address flange leak from gas insulated busbars.
Publications (none)
Final Report (none)
Added to Database 14/10/22