In order to ensure a robust security of supply, a specific organisation has been established at Ellevio that monitors the electricity network around the clock, 7 days a week and 365 days a year.
The international standard SAIDI (System Average Interruption Duration Index) is used to measure security of supply, which is calculated as the sum of all outage periods (excluding planned works) experienced by customers divided by the total number of customers. The index enables comparison with other companies.
SAIDI is an important key ratio for Ellevio and is measured each month and analysed continuously. SAIDI can vary between years depending on whether there have been any major storms during the autumn or winter of the year in question