Although we sold Central Networks in 2011, in 2010 we focussed on distributing electricity safely and efficiently.
Following the sale of Central Networks in April 2011, a deal which formed part of our group cleaner & better energy strategy, we will no longer be operating distribution networks in the UK.
Ofgem monitors the number and duration of interruptions to our supply each year, which are over 3 minutes in length. These are recorded as the number of supply interruptions (power cuts) per 100 customers per year (Customer Interruptions - CIs) and the average minutes without power per customer per year (Customer Minutes Lost - CMLs).
CML & CI Figures for 2010
Customer Minutes Lost
East Actual CML 53.79 West Actual 87.64
Customer Interruptions
East Actual CI 61.78 West Actual 101.62
Central Networks Tree & Vegetation Management Programme
We aimed to provide a continuous supply of power safely and efficiently, but there were many obstacles for us to overcome. Trees can cause unplanned power cuts on our network’s overhead lines and this is a major inconvenience to our customers. We invested heavily and worked hard to bring the trees and other vegetation adjacent to our lines, under control to reduce supply interruptions, and we were involved in cutting edge research to enhance the efficiency of the tree and vegetation programme.
The success of our programme brought about a significant decrease in tree-related customer interruptions (CIs) and customer minutes lost (CMLs). CIs dropped from 9.61 in 2007 to 6.70 in 2010; and CMLs fell from 13.15 to 6.36 in the same period, as illustrated in the table below.
The trend in tree-related CIs & CMLs between 2007 & 2010
| 2007 | 2008 | 2009 | 2010 | |
| CI | 9.61 | 9.01 | 7.24 | 6.70 |
| CML | 13.15 | 9.25 | 5.37 | 6.36 |