The Central Electricity Authority's evaluation for March 2005 identified Kolkata as the city with the lowest number of trippings per feeder and Jabalpur as the one with the lowest outage duration per tripping.
This was CEA's third monthly report, which ranks power distribution systems in big cities on the basis of the number of trippings per feeder and the outage duration per tripping.
Surat in Gujarat was second in terms of number of trippings, followed by Mumbai suburbs and Ahmedabad. Coimbatore in Tamil Nadu was second in terms of outage duration in March 2005, followed by Chennai in Tamil Nadu and Mulund in Maharashtra.
The rating is based on the number of trippings and outage duration of 11 Kv feeders. At present, the evaluation is for towns with a population of more than 800,000.
It will be gradually extended to cover all towns in the country and the CEA proposes to work out reliability evaluation indices in line with international practices.
The top 22 discoms in the country were rated by the CEA. Their performance in March showed that discoms, which had a lower number of trippings per feeder, had relatively longer outage duration.
Kolkata's CESC Ltd had the lowest, 0.13 trippings per feeder, but ranked 20th in terms of outage duration per tripping (149.59 minutes). Madhya Pradesh Poorvi Kshetra Vidyut Vitaran Company got the top rank with 6.43 minutes of outage per tripping, but was 15th on the basis of average number of trippings per feeder.
Delhi made it to the top 10, with NDPL ranking sixth in terms of number of trippings (1.11), followed by BSES Yamuna (1.12) and BSES Rajdhani sharing the tenth position with 1.53 trippings per feeder.
But outage duration was not good, with BSES Yamuna, which had 124 minutes at 18th position, followed by BSES Rajdhani at 19th position (142 minutes).
NDPL was 22nd with 216.66 minutes of outage duration per tripping. Seventeen discoms were not ranked because they did not provide the required information.
