CLP Power said on Saturday that an investigation had found that two supply problems in Tsing Yi in the first week of January were separate, isolated cases involving “different power systems with different voltage levels”.

The company submitted its report to Electrical and Mechanical Services Department on a voltage dip incident at Nga Ying Chau Street Substation on New Year’s Day, having earlier delivered its findings on an outage at On Mei House on the Cheung On Estate, which happened on January 7.

“CLP Power understands the concern of our customers about the two power incidents and has taken immediate additional measures to complete inspection of the power
equipment in the Tsing Yi district,” the company said in a statement.

“Looking ahead, CLP Power will strengthen liaison with property management companies to enhance coordination in responding to incidents and will continue to maintain close communication with community leaders to ensure timely dissemination of information to affected customers.”

The company said that the January 1 incident was caused by a short circuit as a result of insulation degrading inside a cable sealing end. It said an automatic protection system immediately isolated the faulty section. There was a voltage dip, but no power outage, it added.

It said the January 7 incident was down to a waterproofing failure in an 11kv cable joint inside a customer substation. It said 388 customers, about half the households in the building, lost power. It replaced the cable join the same day.

“The company is also inspecting the same type of cable sealing ends and cable joints in other districts,” CLP added.

The company said it was striving to provide a reliable power supply with reference to international standards and best practice.

“CLP Power will work with an independent industry consultant to review the maintenance arrangements of the transmission and distribution system,” it added.

“CLP Power will learn from this experience and implement practical measures to minimise the likelihood of power incidents. CLP Power sincerely apologises again to residents who were affected by the incidents and would like to thank the affected customers and community leaders for their understanding.”