THE National Grid Corp. of the Philippines (NGCP) continues to implement the necessary actions prior to the actual repair of one of its 138 kilovolt (kV) high voltage submarine cables at Amlan, Negros Oriental, the transmission utility, in a release, mentioned.
The said cable was damaged on June 15 during dredging and re-channeling activities undertaken by the Department of Public Works and Roads (DPWH) along the city’s Bio-os river.
The two circuits of the 138kV submarine cable have a total capacity of 180 megawatts (MW).
NGCP said that with the loss of a circuit due to damage from the incident, the transmission capacity of the submarine cable between Negros and Cebu was halved to just 90 MW.
The incident caused congestion along the Negros-Cebu transmission corridor affecting the Negros and Panay subnets, he said.
The NGCP coordinated with relevant local government units in Amlan, the Department of Environment and Natural Resources (DENR) and DPWH regarding the incident, as well as the Department of Energy (DOE) to request their support for its repair.
The unique underwater nature of the facility requires a pre-inspection of the nature and extent of damage before actual repair, the utility said, adding that the cable manufacturer and service provider are currently in the process of a “cut and inspection” of the submarine cable. to determine this.
The statement further stated that, subject to the manufacturer’s findings, the target completion of repairs is estimated in February 2022 if the water inlet does not exceed 400 meters and only 500 meters of the cable using the spare parts available. must be replaced.
âIf the water penetration exceeds 400 meters, it is necessary to replace a longer cable length or to fabricate a new assembly; further extend the repair time. The penetration of water up to the submarine cable is the main factor taken into account in determining the best course of action, âhe added.
The NGCP also noted that the incident caused a sharp increase in electricity prices in the Negros and Panay Islands, as reported by the Independent Electricity Market Operator of the Philippines (IEMOP).
However, the Energy Regulatory Commission (ERC), in its letter to the Philippine Electricity Spot Market Corporation (PEMC) dated September 20, 2021, ordered the latter to suspend the collection of congestion charges and other applicable charges, and to reimburse those collected in previous billing months until the affected line is fully restored and resumes normal operations.
âRepairing damaged submarine cables is a bit more complex than restoring ordinary transmission lines. We need sufficient time to determine the exact extent of the damage before proceeding with the actual repair, âthe company said.
âThis involves diving, crane lifting and testing activities which must be carried out by experts with specialized equipment. We are well aware of the difficulties this incident has caused, and we are doing everything possible to speed up the process, âhe added.