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Projects: Projects for Investigator
Reference Number NIA_NGET0178
Title Environmental Containment solutions for Midel 7131
Status Completed
Energy Categories Other Power and Storage Technologies(Electricity transmission and distribution) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields PHYSICAL SCIENCES AND MATHEMATICS (Chemistry) 50%;
ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 50%;
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 February 2016
End Date 01 July 2017
Duration 17 months
Total Grant Value £310,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid Electricity Transmission (100.000%)
Web Site http://www.smarternetworks.org/project/NIA_NGET0178
Objectives The objective of this project is to research and document appropriate environmental containment solutions for Midel 7131 filled transformers on National Grid electricity substations. This will include a study of how bund pumps and separators will ensure that Midel 7131 can be prevented from polluting the environment. The project also aims to enhance industry understanding of the biodegradation of Midel 7131 in a substation environment. The three reports delivered against each of the three phases outlined in the Scope section will provide National Grid with the knowledge required to inform the development of relevant policy documents and technical specifications.
Abstract National Grid is in the process of deploying its first Midel 7131 filled 400kV transformers to a new build urban site. Whilst Midel 7131 has benefits in reduced costs of civil works, such as eliminating the need for fire walls, the industry does not currently understand how Midel 7131 behaves when released in a typical substation; the options available for accelerated degradation; whether existing secondary containment solutions are appropriate for applications where Midel 7131 is used and what alternative containment solutions might be available. The use of Midel 7131 presents a challenge to the industry in how to ensure that when the transformers leak the Midel 7131 does not contaminate the environment. This is because Midel 7131 has different physical and chemical properties to the traditional mineral oil and so requires innovative ways to manage and contain any leaks. National Grid now needs to understand the impact on civil infrastructure of , replacing a mineral oil filled transformer with a Midel 7131 filled transformers, and what measures it might need to put in place to address fundamental differences in Midel 7131 and mineral oil on new transformer installations. National Grid has a track record of protecting the environment by ensuring that no oil leaks escape into the environment. National Grid has processes and specifications in place that dictate how civil infrastructure is built to manage mineral oil leaks from transformers on substations. However given that the physical and chemical properties of Midel 7131 differ from mineral oil (most notably, its specific gravity and biodegradability) National Grid needs to: Be assured that the existing infrastructure remains fit for purpose or understand if there is a need to develop its civil infrastructure to keep pace with recent developments in insulating liquid applications in particular the introduction of Midel 7131. Understand how Midel 7131 behaves and biodegrades in a substation environment and how these properties can be used in the event of an accidental spill to ensure maximum environmental protection. Know that the Midel 7131 containment solution developed by this study is not only fit for purpose but that it is adopting best practices in civil engineering solutions that will provide value for stakeholders. This study will investigate the behaviour of Midel 7131 in a substation environment and will recommend suitable containment solutions when the "oil" escapes from transformers..Note : Project Documents may be available via the ENA Smarter Networks Portal using the Website link above
Publications (none)
Final Report (none)
Added to Database 14/08/18