3.30am outage suspected to have been caused by lightning, says Sarawak Energy

KUCHING, Nov 27, 2016 - An outage occurred about 3.30am early today, affecting Sibu, parts of Mukah and 30 per cent of Kuching customers, due to a double circuit tripping at the 275kV Kemena-Selangau Line.  

A statement issued by Sarawak Energy Berhad (SEB) today said the circuit tripping was suspected to have been caused by heavy lightning activity in the area.  

The statement said SEB's system defence scheme activated immediately and Kuching was successfully islanded to minimise the number of customers affected.  Full restoration to all affected customers was at 6.14am.

"This is a separate incident from the tripping at Oya-Selangau 275kV transmission lines yesterday evening.  Sarawak Energy is currently investigating the cause of these two outages," the statement added.

It said that the risk of incidents like these would continue until the completion of the 500kV second transmission line - potentially two to three major outages could happen in a year until critical parts of the project are completed.

"The 500kV transmission line will provide a second backbone transmission, avoiding major outages in the event of a double circuit trip such as what had happened in November 2015 and January 2016.

"With two parallel transmission backbones, power supply will continue from our major generation power plants concentrated in the north such as the Bakun and Murum HEPs to customers in Sarawak, particularly in the more densely populated southern region should the lines trip.

"The completion of the 500kV backbone transmission line is facing major delays due to wayleave issues.

"We seek the cooperation of all parties, especially landowners, for Sarawak Energy to complete the 500kV transmission project without further delay.  

"For the time being, we are doing all we can to manage the present system through close monitoring of the vulnerable sections of the lines.

"Sarawak Energy regrets the inconvenience caused to our valued customers.  Please be assured that our response teams are continuously on standby 24-7 to ensure fast restoration in the event of an outage," the statement said.