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Projects: Projects for Investigator
Reference Number NIA_UKPN0011
Title Small Bore Cable Replacement Technology
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 ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
Eastern Power Networks plc
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 September 2015
End Date 01 April 2017
Duration 19 months
Total Grant Value £1,114,650
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , Eastern Power Networks plc (99.998%)
  Other Investigator Project Contact , UK Power Networks (0.001%)
Project Contact , South Eastern Power Networks plc (0.001%)
Web Site http://www.smarternetworks.org/project/NIA_UKPN0011
Objectives The Small Bore Cable Replacement Technology project intends to demonstrate emerging techniques for the replacement of EHV cable as an alternative to traditional open cut lay techniques currently used. Technologies have been trialled on large cross section area cables in rural locations for the replacement of fluid filled cables. These however have not yet been proven on small bore cables in urban environments that may be in close proximity to other circuits or services. Therefore this project plans to trial these emerging techniques at small bore cable routes in urban environments that are close to other circuits and cables. Demonstrating that such cable replacement techniques can be employed may provide the ability for the reduction of: EHV cable replacement costs; cable leakages (fluid and gas); Customer Interruptions; and Customer Minutes Lost. Therefore facilitating a cost-effective cable replacement programme. The main risks for the project will be impact on customers whilst carrying out the trials due to failure of the new methods being tested. For this reason initial trials will be carried out on inactive sections first. The following will be considered when assessing whether the project has been successful: A list of suppliers and their contact details that provide services for the replacement of fluid filled cables, along with the techniques (tested and untested) they are able to offer as an alternative to the traditional open cut lay approach. Alternative replacement techniques have been undertaken and tested at the trial sites and replacement circuit is commissioned. An understanding through demonstration whether there are effective alternative solutions to the current open cut technique for EHV cable replacement. The dissemination of trial results with other GB DNOs.
Abstract Within UK Power Networks operating licence areas there are 6,431km of cables running at 33kV, 66kV and 132kV. Within all GB DNOs there are approximately 24,275km EHV and 132kV cables in operation that this technology could be applicable to. These cables were installed since the 1900s, with the majority being installed in the 1960s. As these cables age the likelihood of faults increases. This can be in joints, ancillary equipment or along the cable itself, due to degradation of materials of construction. The only method available to reduce customer interruptions on cable that has faulted multiple times is to replace it. The current accepted practice for the replacement of EHV cable is the open cut lay of a new parallel route, followed by the abandonment of the old cable, including the decommissioning of the oil or gas cable. This represents a significant investment in order to replace EHV cables. A number of new technologies are becoming available to enable the replacement of a fluid filled cable by removal of the existing cable and insertion of a new solid cable along the same route. These technologies have been trialled on large cross section area cables in rural locations however they have not been proven on small bore cables in urban environments that may be in close proximity to other circuits or services. If these technologies could be tested within real-environment network conditions this would enable GB DNOs to significantly reduce the cost of replacing EHV cables, and thus provide better value to customers and allow more cables to be replaced reducing fluid leakage, gas leakage, Customer Interruptions and Customer Minutes Lost. The project will test emerging replacement techniques of EHV cable as an alternative to traditional open cut approaches currently used at urban sites. The main activities will be: Identify and generate a list of potential suppliers involved in the replacement of EHV cables through market assessment. Contact the identified potential suppliers and gather an up to date detailed understanding of the emerging tested and untested techniques alterative to using open cut lays in replacing EHV cables. Review and assess the emerging techniques highlighted by the suppliers and select the techniques to be tested. Run a tender process to identify the Supplier for the replacement technique (only if it is found that several providers can provide the solution otherwise single source against the supplier initially identified) Development of an evaluation pro forma to assess the performance of each trialled replacement technique. Assessment of each replacement technique employed. This assessment is proposed to cover costs, time at site, limitations of the technique and impacts on adjacent circuits. Peer review undertaken of results with other DNOs. This project will be carried out in two phases: Phase 1 - Trial on electrically isolated cables The purpose of this phase will be to test the new technology in real ground conditions - in close proximity to other non-UK Power Networks assets and in close proximity to other (inactive) circuits. During this trial other UK Power Networks circuits in close proximity will be closely monitored to confirm the impact of the new technology on them and to identify if risk of damage to adjacent assets can be minimised. Phase 2 - Trial on temporarily electrically isolated power cables. This second phase will only be carried out subject to successful outcome of the first phase ofeach technology. In the event that one technology is successful and the second is not, only the successful technology will be brought forward to this phase. In this phase the technology will be tested on electrically active cables. These will be cables which have been temporarily isolated due to faults, leaks or ongoing repairs. The technology will be trialled on sample routes where each technology will be trialled on a different section where practicable.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 14/12/18