TAGBILARAN CITY, Philippines — Another transmission hitches caused power shutdown in Bohol from past 1 p.m. to around 3 p.m on December 27, the 4th time this month.
Betty Martinez, spokesperson for National Grid Corporation of the Philippines-Visayas, explained that Tuesday’s blackout was due to the momentary tripping of the 138-kilovolt Ubay-Corella line.
The three previous power shutdown hitting Bohol were on December 3, 4, and 17, the last two of which were unscheduled, similar to last Tuesday’s, but attributed to hitches on the Leyte side of the grid.
The December 17 blackout actually came in two instances: First from 9:56 a.m. to 10:31 a.m. and then from 11:18 a.m. to 6:00 p.m. Martinez said NGCP attributed it to the tripping of the Ormoc-Maasin 138-kV Line 2 as winds affected Leyte.
NGCP had earlier explained that the common cause of unscheduled power interruptions is “vegetation” such as coconut fronds, branches of trees, or any even banana leaves touching the transmission lines, and causing load interruptions.
The power interruptions on December 3 was the first and only scheduled power shutdown this month. It was done for the line upgrading activity as a second line, or Line 2, was added to the Leyte-Bohol grid that supplies electricity to Bohol through submarine cables.
The December 3 shutdown was supposedly for 13 hours only (from 4:00 a.m. to 5:00 p.m.) but it stretched to 20 hours and a half. The NGCP managed to restore power only at 12:27 a.m. the next day, on December 4, attributing the matter to bad weather that made it difficult for its linemen and engineers to undertake the procedure.
But shortly after power was restored on December 4, an unscheduled power interruption affecting the entire province followed at 1:21 p.m. until 2:02 p.m. The NGCP attributed this to another tripping of the 138-kV Ormoc-Maasin Line 2.
The last unscheduled blackouts in entire Bohol were on November 18, June 11. July 9, and March 5, when a 13-hour no-power was experienced due to the shutting down of the 138-kV Maasin-Ubay cable line for its annual preventive maintenance.
The “bad weather” factor in the Leyte side was among the priority issues that Governor Edgar Chatto sought to address when he assumed his first term in 2010. He mobilized teams to start researching on the possibility of establishing Bohol’s own power supply, inland.
When Bohol experienced total power shutdown from Leyte for over a month after super typhoon Yolanda, the governor drew multi-sector support and several consultations with experts. He then issued an executive order in January 2014, creating the Bohol Energy Development Advisory Group (BEDAG).
The BEDAG initiated the formulation of the Bohol Island Power Development Plan (BIPDP) with the assistance from the United States Agency for International Development-Advancing Philippine Competitiveness (USAID-COMPETE) Project.
The BIPDP is a long-term energy plan for the province, aimed at ensuring security of supply when needed; reliability and resiliency that entails climate-proofing of supply; and affordability.
In a full council meeting last week, the Provincial Development Council (PDC) presented the power supply projects given consideration by the Regional Development Council, and among these are: Cebu-Bohol Inter-connection in February 2021; Tagbilaran substation in December 2020; and feasibility study (FS) on Visayas-Mindanao Interconnection.
In the BIPDP load forecasts, “approximately 87 percent of the 67-megawatt power consumption of Bohol is being supplied for by the Leyte-Bohol transmission line connecting the island to the main Visayas Grid.
“Bohol’s total electricity demand ranges from 64 megawatts to 67 megawatts and with the economic growth, it is expected to increase to 75 megawatts by 2019 and up to 113 megawatts by 2043,” it said.
BEDAG had earlier “endorsed the transmission plan presented by NGCP where an alternate Cebu-Bohol transmission link shall be provided to ensure connectivity of Bohol to the main Visayas Grid.
This alternate transmission link will also allow export of excess power from Bohol if more generating resources are developed within the island,” as earlier pronounced by the governor. (FREEMAN)