go to top scroll for more


Projects: Projects for Investigator
Reference Number NIA_UKPN0014
Title Solid Cable Replacement Prioritisation
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 February 2017
Duration 17 months
Total Grant Value £141,056
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_UKPN0014
Objectives The objective of this project will be to identify solid cable assets operating at 33kV, 66kV and 132kV where it would be cost beneficial to customers to replace, as opposed to carrying out multiple fault repairs. By carrying out this analysis a cost benefit can be proven for the replacement of old cables to ensure best value for customers. The specific objectives are: Collation of historic faults with asset registers in place (linking to the fault to cable information)Analysis of faults and trends for cables operating at 33kV, 66kV and 132kV, leading to identification of factors that affect the likelihood of failure of solid cables Collation of all sources of information into a model to allow identification of cables at increased risk of fault Output of model to identify cables where replacement would be beneficial to customers The success of the project will be judged against the four objectives described above: Linking of historic faults with asset registers to produce picture of historic cable faults (reason for fault, type of cable used, type of lay, age, location, etc. ) leading to production of a table of historic faults. Identification of factors that affect the likelihood of failure of a solid cable, leading to the production of a short report identifying trends to be considered what planning asset replacement of solid cables. Collation of all asset registers to produce model with sufficient asset data to allow identification of high risk/customer cost beneficial cables. Output of model - identification of cables where it is more beneficial to the customer to replace the cable rather than repair.
Abstract Within UK Power Networks operating licence areas there are 4,022km of solid cables running at 33kV, 66kV and 132kV. Within all GB DNOs there are 18,098km of solid cables in operation at these voltages. These cables have been installed since the 1900s, with the majority being installed in the 1960s. As these cables age the likelihood of faults increase. This can be in joints or along the cable itself, due to degradation of materials of construction. The current accepted practice for resolution following fault is to replace a short section in the location of the fault with XLPE cable and re-energise the circuit. While this will restore supply to customers following the fault it does not represent best value to customers, as over years multiple faults may cost more than overlays or replacing of sections of cable with modern cable with a lower likelihood of failure. Although no HI model for solid cables exists, anecdotal evidence suggests: Paper Insulated Lead Covered (PILC) cable has a higher rate of failure over time when it is positioned on steep gradients Early versions of XLPE have a higher incidence of failure compared to historical PILC cable. Solid cables which have faulted previously have a higher fault incidence rate Generally older cables have a higher fault incidence rate However, the above anecdotal evidence has not been analysed to prove it is the case. This prevents investment funding for solid cable replacement as it cannot be shown there is a benefit to customers in replacing the cable. The project will review fault history of solid cables to identify how prioritisation of investment can be made to reduce CIs and CMLs. It is planned this will be carried out by: Collation of all recorded faults on the network Extraction of all data on cables (GIS, asset registers, cable loading history) Analysis of faults against cable type (construction type, location, voltage, age, type of lay, historic loading) Identification of factors that affect the likelihood of failure of solid cable The above analysis will be based on faults at EHV voltages, to enable sufficient data to be collected for statistical analysis. Following analysis of historic faults and identification of solid cable failure factors: Development of model to input all current data on cables (construction type, location, voltage, age, etc.) to calculate prioritisation of replacement for cables. Model to enable to the comparison of costs of a cable to identify where it is beneficial to customers to replace a solid cable (i.e. cost of CIs/CMLs outweighs the cost of replacement) Modelling and HIs will be calculated for cables operating at 33kV, 66kV and 132kV only, as these cables are the most costly to replace and will add the most value to customers.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