ERC: NGCP 'failed in obligation' in Panay Island blackout

The National Grid Corporation of the Philippines (NGCP) failed in its obligation to report a significant loss of power in Panay Island that set off a three-day blackout, according to the Energy Regulatory Commission (ERC) on Thursday.

During the congressional inquiry on the matter, ERC chairperson Mona Dimalanta said that under the Grid Code, the system operator such as the NGCP has the obligation to report a significant incident to the ERC within 15 minutes via text message and subsequently submit an initial written report within an hour of the incident.

“The first outage of the (Panay Energy Development Corporation) PEDC 1 unit...it went out at 12 noon...we did not receive a significant incident report [from NGCP]. The first report that we got is already following the cascading [tripping of power plants] at 2 pm,” Dimalanta said.

The power outage occurred on January 2 or a day after New Year’s Day revelry. It was followed by other tripping in PEDC Unit 2, Palm Concepcion Power Corporation (PCPC), and other plants then tripped around 2:19 pm.

“Under the Grid Code, the loss of a large generating unit is considered a significant incident. In the Visayas, as provided by the Grid Code, anything above five megawatts is already considered a large generator and is already a significant [incident]," added Dimalanta. 

She said that under the Grid Code, the system operator such as NGCP is “responsible for ensuring that load-generation balance is maintained during normal, alert and emergency conditions." 

Dimalanta said that since Panay island outage which started last January 2 is a case of a credible n-1 contingency where there is no temporary System Integrity Protection Scheme (SIPS) in place to avoid spreading of the disturbance, NGCP should have taken the following measures:

• Generating unit re-dispatching
• Usage of voltage and/or power flow control on regulation transformers
• Network re-configuration
• Manual load dropping
• Generating unit tripping

“These are the actions that we look forward to receiving in the report of the system operator (NGCP) in the course of our investigation,” Dimalanta said.

NGCP Assistant Vice President and Head of National System Clark Agustin, in response, reiterated that NGCP followed all protocols in reporting the outages. 

"Based on our data, all the voltage, frequency are within limits [after PEDC 1 went down]. There were no overloaded transmission lines, the operating margin was sufficient, so we continued with our normal dispatch process," Agustin said.

"However, at 14:19 (2:19 pm) multiple power plants tripped almost simultaneously. Almost 300 megawatts tripped. So what happened, Panay is left with no local generation. Emergency state na po tayo," Agustin added. —VAL, GMA Integrated News