Thursday, July 13, 2017

NGCP assures 24/7 work
to get partial power Aug 1

TAGBILARAN CITY, Bohol, July 12 (PIA)--The National Grid Corporation of the Philippines (NGCP) is simultaneously working with other power stakeholders to come up with the most immediate and most sustainable soluition to the Leyte earthquake caused downed power in at least three provinces.

NGCP Visayas corporate spokesperson Betty Martinez assured this as they are looking at options to allevaite the power needs of Visayan and Samar consumers.

Whate are these options?

EDC Power Supplied from Kananga

After the earthquake, the Energy Development Corporation (EDC) which operates the severely affected geothermal power plants assessed the damage and issued an advisory: they may be able to salvage 40 MW from their Kananga power plants.

Kananga power plants, which include the Upper Mahiao, Manahagdong and Malitbog, in Kananga Leyte, has shown it has sustained some damage but has hopes it can pass to Ormoc Substation some of its salvaged geothermal power.

This would then be distributed to Samar, Leyte and Bohol, according to Gil Listano, NGCP Assistant Technical Officer during a press conference this afternoon at the NGCP.

But then, just as the NGCP attempted to energize the 230 KV line to give the start up power to Kanaga to run their turbines, the EDC has to ask the NGCP to cut the back-feed supply, added Atty Alabanza, NGCP Corporate Communications Chief.

"Last July 10, NGCP initially energized EDC’s Marshalling Substation to provide feedback power to EDC’s Upper Mahiao and Malitbog geothermal power plants but de-energized again at EDC’s request due to technical difficulties by a still undetermined cause," NGCP Visayas spokesperson Betty Martinez confirmed.

As of the moment, EDC is still testing and checking again to find the problem, informed Atty Alabanza.

When the testing is okay and the EDC gives the go signal, NGCP said they can flow the 40 megawatts to Samar, Leyte and Bohol.

Considering the need from the three provinces, Bohol could get at most some 15 megawatts more.

With BDPP (12MW), Hanop0l (7.5MW) and Sta Clara (1.2), this is not even half of the 80MW demand in Bohol.

When this is online, by July 18, there should be a few megawatts of power from Leyte, Usec Fuentebella said in a radio interview.

Cebu Negros Panay (CNP) Grid supply

With the EDC marshalling station (that which pools all plant generated power from the geothermal plants to flow to NGCP lines) still being tested, NGCP has to put up in record time a bypass line.

The nearly 50 kilometer bypass line is strung from Tabango SubStation in Leyte (which receives the 230 KV submarine cable line from Cebu) to Ormoc SubStation.

This will allow power from CNP, (if there is enough available) to fill up some of the power needs in calamity hit Leyte, Samar and Bohol, said NGCP spokesperson Betty Martinez in an advisory.

Department of Energy (DOE) Undersecretary Wimpy Fuentebella has said Leyte and Samar has a peak load of 290 megawatts, and a part of that could be supplied by CNP via the 230 KV Daan Bantayan Cebu to Tabango submarine cable in Leyte.

From Tabango, the 230 KV CNP excess power supply goes to Ormoc Substation where the 230 KV supply is transformed to 138KV so it can be supplied to Samar, Leyte and Bohol, NGCP Assistant Technical officer Listano said.

While the bypass line was strung so NGCP could feed in the CNP supply to Ormoc, NGCP has to simultaneously test its transformers.

NGCP spokesperson and also Public Affairs Department chief Atty. Cynthia Alabanza stressed during the press meeting that the NGCP has to do a battery of tests to make sure that their lines are stable and safe, otherwise it explodes, may cause injuries and prevent further damage.

This is not an issue on the equipment, this is not a technical failure because these were located within the epicenter and a very strong aftershock, Atty. Alabanza told the media.

The tests however proved that of the 6 NGCP Ormoc Substation transmitters, only one is available, the rest are damaged, Listano shared.

Apparently, NGCP hinted that the problem with one transmitter under warranty, is only the insulation and if the manufacturers can vouch for it, then we can energize it, Listano added.

He did not however say when the manufacturer would come and see the transformer.

Option to the busted transformers:
A: Compostela and Banilad transformers

Listano however said the NGCP has one more option: to bring in a 150 MW transformer from Compostela Cebu and another standby 100 MVA transformer now stored in Banilad, also in Cebu.

The Compostela transformer is accordingly of the same size and can fit a location inside Ormoc Substation.

Another 100 MVA transformer now in Banilad can also be brought to Ormoc, NGCP said.

The transformer has been shut down, to be crated, hauled off to a barge, towed to Ormoc, haul it over land and install it before commissioning.

Another concern floated during the presscon was the factors in transporting the transformer.

With the earthquake possibly weakening some roads, allowing the heavy transformer to pass may be an issue.

But, barring any more problems, this should be running by July 31, both Listano and Atty Alabanza said.

July 31 is in fact a tight target, there is no elbow room as well, Alabanza forewarned.

With one if: as long as there is an excess supply from the CNP. 
Alabanza, who played the devil's advocate during the press con, also shared that even Cebu is having low supply at the moment.

B: Reconfigured 230KV CNP excess power

The proposal is for the 230 KV power in Compostela to be reconfigured so that it does not go to the Compostela step up transformers and get into the submarine cables to Tabanga as 138KV.

According to the NGCP, their engineers have proposed the reconfiguring of the Compostela -Daanbantayan-Tabango 230 KV line to allow 138KV to pass through.

This is so that as soon as the power supply arrives in Ormoc, it need no transformers and it can be readily supplies to distribution companies who will supply consumers.

NGCP spokesperson for the Visayas, Martinez confirmed: 230kV lines from Compostela, Cebu will be reconfigured and stepped down to 138kV lines in order for power to reach Ormoc and be readily received by Distribution Utilities (DUs), she wrote in an advisory released July 12.

This, we can surely work on, but we have to tell you that when we energize, it is only that time that we will know if we have problems along the way, Atty Alabanza intoned.

While the timeline for this is July 18, the NGCP again added that this is considering that there is an excess power from the CNP grid.

Power barges

NGCP also leaked another option: the power barges.

According to Listano, there have been three power barges identified: one 20 MW now in Cebu, another 20 MW in Panay and one in Davao.

But with power barges owned by private companies, the NGCP can only put in the necessary lines to tap the barge power to their transmission line as soon as the barges come.

Power barges which have been identified for Biliran in Leyte, Ormoc and Abatan River in Cortes have been eyed to supply the need.

Listano said the usual process is for the power barges owners to call NGCP to tap their barges from their moorings, but he said, they have not received any calls to tap as yet.

This morning Usec Fuentebella also shared that while the DOE commits to sending the barge in Bohol, there must be prior arrangements as to the cost of transporting the barge, who talks with the barge owners, what is the agreement with the distribution utilities.

He also assured that by August 1, at most is that 50% of Bohol power would be restored.

As this went on, the NGCP assures its customers and the public that it is pooling all its resources and exerting all efforts to restore, even partially, power transmission services by the July 31 deadline, as set by DOE, or earlier, Martinez said. (rahc/PIA-7/Bohol)

Members of the Bohol Media use the Kananga Geothermal Power Plants as backdrop for a souvenir photo during a visit to Tongonan in Leyte last summer. The three power plants pool their supply to Malitbog where a marshalling plant allows EDC to distribute the power to NGCP transmission lines. This plants have been partially damaged. (foto by Ric Obedencio)

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