The Environment & Ecology Bureau has said it is very concerned about a voltage dip incident in CLP Power Hong Kong's 400kV overhead power supply system connecting Yuen Long and Shenzhen early this morning.

Earlier this month, the Secretary for Environment & Ecology indicated that CLP must examine its company culture and its management of the entire power supply system to identify the root causes of such incidents and make improvements to reduce the chances of them occurring.

He also requested that CLP allocate resources for an independent consultant, who would be engaged by the Electrical & Mechanical Services Department (EMSD) to conduct a re-examination of all voltage dips and power supply interruption incidents over the past three years, as well as a comprehensive review of the company's management system. The consultant would then provide comprehensive recommendations on how to enhance the stability and reliability of the system. CLP was required to complete these tasks and submit a report within 12 months.

According to CLP, today's voltage dip incident occurred during a Thunderstorm Warning, with the 400kV overhead power supply system affected by unstable weather.

The Secretary for Environment & Ecology was of the view that CLP should not wait until the completion of the review to enhance the power supply system, particularly the lightning protection capability of 400 kV overhead line towers. He has instructed the Director of Electrical & Mechanical Services to urgently follow up on the matter with CLP with a view to reducing risks, given the high frequency of Thunderstorm Warnings during the summer months.

EMSD has requested that CLP identify the cause of the incident as soon as possible, formulate improvement plans and submit a detailed report within four weeks, in accordance with the Electricity Ordinance.

Moreover, EMSD will form a task force to follow up on the improvement plans proposed by CLP today.

The task force will also review whether the company's timetable for implementation of measures can be accelerated, and if there are any additional measures which can assist in enhancing the power supply system's ability to withstand the impact of inclement weather.

The Director of Electrical & Mechanical Services will meet CLP's senior management on a regular basis to review the progress and effectiveness of all improvement measures, and report to the Secretary for Environment & Ecology.