Review Incident Shin.. - authority for electricity regulation, oman

5. CONCLUSIONS
Based on the review described in the previous chapters we conclude that the duration of
the outage was influenced by a number of factors:
The first and most important factor is that the supply to the Shinas area is not (n-1) compliant.
If the supply had been (n-1) compliant the permanent trip of a single circuit would not
have led to any supply losses for customers. Although the network should have been redundant
according to the standards in Oman and international best practice, the process is
well underway with the project to provide this redundancy in the tendering phase.
Since it was recognized by OETC that the line was not (n-1) compliant and because a line
fault is not uncommon, we would expect proper preparation including a comprehensive
plan for a line fault in the Wadi Jizzi – Shinas line.
With respect to this preparation, fault distance indicators installed at the Wadi Jizzi grid
station could have reduced the time for locating the fault location (2.5 hours) significantly.
Since spare parts were only completely available about 14 hours after the materials that
were needed for repair of the line were identified, we conclude that spare parts were not
available or not available on a limited distance to the line. Having relevant spare parts
available would have reduced this time of 14 hours significantly.
Since we have only seen an expired maintenance contract, we are unable to confirm that a
maintenance contract for the Wadi Jizzi – Shinas line was in place at the time of the incident.
We found some issues which did not influence the duration of the outage significantly but
could also be improved. Firstly, we found that OETC relied on the assistance of other parties,
e.g. a team from MJEC assisted the line patrol team on an ad-hoc basis. Plans for incidents
of this type should include formal arrangements for assistance from third parties.
The organization of the emergency organization was ad-hoc. We do suggest developing
and using clear procedures for organizations of emergency situations as proposed by
the Contingency Planning Code. This includes system normalization procedures and system
incident procedures. Moreover, it includes the establishment of an incident center, a
communication plan and the organization of the restoration and repair, including the
role and workload of the operation engineer and coordination of the outage. Finally, we do
Review Incident Shinas August 2007 19 09.10.2007
vs. 2 (final)