Rawwater provides leak and defect sealing solutions using low melting point alloys called M3. Rawwater’s proprietary technology includes M3Spray in which molten alloy is sprayed directly against a flowing liquid leak to stem it. 

Building on the leak sealing feasibility work carried out previously, the project will focus on the testing of Rawwater’s M3Spray for sealing realistic transformer leak scenarios, including on decommissioned transformer parts. Deployability of the solution including access nozzle development for manual application and semi-autonomous robotic integration for controlled deployment will be tested. Alloy containment to ensure that metal particulates are contained and controlled will also be tested. 

This work will culminate in a pilot deployment on a transformer (TRL7) on the NGET estate. Following an initial period of 3 months, there is the option to extend the project to include further robotic integration and further scenarios to a wider range of leaks.

Benefits

National Grid procures an increasing amount of mineral oil for top up purposes every year. Fixing the oil leaks will not only reduce the oil requirement but beneficial for overall asset lifecycle health. Fixing the leaks will reduce the mineral oil top up requirements, maintain health, reduce travel to substations (Scope 1 emissions), and maximise the network capacity by reducing the maintenance outages on transformers and other assets. Transformer replacements in RIIO-T2 period is budgeted at over £240M. Savings made due to spend in T1 on asset life extension is £97M. If more transformers can operate longer than currently planned, significant savings can be made, orders of magnitude above the spend of this project, and the end solution.