LV Interconnected Pairs
Status:
Complete
Project Reference Number:
NIA_UKPN0074
STRATEGY THEME:
  • Optimised assets and practices
START DATE:
END DATE:

Project summary
Funding mechanism:
  • NIA_RIIO-1
Technology:
  • Active Network Management
  • Asset Management
  • Control Systems
  • Fault Current
  • Fault Level
  • LV & 11kV Networks
Expenditure:
£661,000
Summary
Learnings
Documents

Electricity networks contain equipment that operates at different voltage levels. Domestic customers are fed from the low voltage (LV) network. The LV network is fed from the high voltage (HV) network. The HV network is fed from the extra high voltage (EHV) network, and so on. When a fault occurs on the HV network, there is a cascading impact to the LV network that it feeds. 

 

In more modern parts of the network, automation is used to prevent an LV outage when there is a HV fault. However, a large proportion of the LV network does not have any automation.  

 

For the majority of LV networks, when a HV fault occurs, the LV network fed from the affected substation loses supply. This means that all customers fed from that substation experience a power cut. 

 

Benefits

With the introduction of LV Interconnected Pairs, restoration times to those affected on the LV network will be reduced due to enhanced automation. 

 

Gross financial benefit if all eligible substations received interconnected pairs technology: £1.75m per year

This is made up of CI and CML benefits. 

[benefit per substation = HV fault rate x customers per substation x time that automation would save]

On average, we estimate that it takes 90 minutes to apply a backfeed.

The potential benefits across LPN, EPN and SPN are technically the same. The actual benefits will vary on a case by case basis based on network behaviour, such as where HV faults occur. This is analogous to the benefits from the Automated Power Restoration Software, which are reported each year in the E6 submission. See page 27 onwards in this document for more information on APRS: http://library.ukpowernetworks.co.uk/library/en/EnvReports201617/Environment%20and%20Innovation%202016-17%20Commentary_Final.pdf