LIHU‘E — With Kaua‘i’s power grid now back online, it’s time to shine a little light on what caused Wednesday’s island-wide electricity outage. “We’re proud because this type of incident is far and few between for us, and we responded
LIHU‘E — With Kaua‘i’s power grid now back online, it’s time to shine a little light on what caused Wednesday’s island-wide electricity outage.
“We’re proud because this type of incident is far and few between for us, and we responded very appropriately,” said Mike Yamane, chief of operations at Kaua‘i Island Utility Cooperative, on Thursday. “The system responded very appropriately, and the only glitch we had was getting the Kapaia generation up.”
The first order of business was to isolate the event, then to restore and stabilize power and finally to figure out what happened, Yamane said.
The Port Allen generators are still down.
“Brown outs are not expected,” he said. “What we have now can easily meet the peak.”
KIUC said a transformer failure at 5:15 p.m. on Wednesday caused generators to trip offline and trigged the outage. It occurred just before standard peak evening customer usage, usually between 6 and 9 p.m., during which the island load averages 65 megawatts.
Had a transformer failed at another location, it would have isolated the blackout to a smaller area, Yamane said. Second only to a generator in terms of size and cost, he said the transformer converts generator voltage to transmission voltage.
“There are (transformer) devices all over the island, and the significance of this device depends on where it happens,” Yamane said. “Because it happened at Port Allen, it took all of the generators off line.”
Approximately a dozen utility workers went about isolating the equipment failure, he said. The dispatch center at Port Allen directed crews to restore power to the rest of the island.
The system needed all available power, and the flash shut down the main 24-hour generator at Kapaia and presented a real concern. As smaller motors came online, the Kapaia generator had to cool thoroughly before restarting, he added, and it wouldn’t start again until around 1:14 a.m.
Low electricity demand during late-night hours helped the system come back online without the Kapaia generator. If it had not started by 6 a.m., then increases in demand would have created another problem.
“Anytime there is an imbalance, then we have to have load shedding to keep the frequency up there,” he said. “Right now, we are comfortable because the peak (65 to over 70 MW) is not that high.”
Yamane is aware of only one location that remained without power after all circuits were reported restored at 10:30 a.m. Thursday.
The Halelani Townhomes in Puhi reported a problem with their circuit when the power came back on, and it took crews until nearly 2 a.m. Thursday to restore service.
When the Port Allen transformer blew, witnesses assumed the big fireball flash that engulfed the system was a structural fire. A failed insulator caused the short circuit and created the flash incident, but it did not spread.
No one was hurt during the incident or during repairs, Yamane added.
“This doesn’t happen a lot and it is preventable with due diligence, but sometimes you can’t see it coming,” he said. “That is why the system is set up the way it is to shut on its own and avoid further damage or worse damage.”
A series of three smaller generators remain out of service in Port Allen.
All the generators on Kaua‘i burn diesel fuel. The Kapaia generator also burns naphtha.
Once everything was running, the next step is an analysis to study detailed technical data to look at improving management of similar situations in the future.
“That is an ongoing process for us,” he said.
Routine inspections serve to help prevent these types of equipment failures. Yamane said they look for signs of heat wear and that it wasn’t detected.
KIUC communications and administration staff, including Yamane, remained at the KIUC office in Lihu‘e to handle media and customer calls update the KIUC’s Facebook page.
Yamane said they got calls from people asking if they should unplug appliances to help ease the load when the power comes back on. He was impressed with that concern but said the public should expect enough power for them when power is restored.
“From a utilities standpoint, we can’t ask them to pull plugs and we just ask them to be patient,” he said.
Yamane encourages members to visit the Facebook page often for other information about meetings and programs, as well as for tracking the outage and storm repair bulletins.
A power outage as widespread as Wednesday’s creates a public safety issue. Kaua‘i County responded.
“We are very fortunate that last night’s island-wide power outage did not result in any major public safety issues,” said county spokeswoman Sarah Blane. “There were no outage-related emergencies reported by our police or fire departments.”
Blane said a coordinated effort to keep the public safe included county agencies in conjunction with KIUC, the state Department of Transportation and local media. Police Dispatch did report technical problems between 5:30 and 6 p.m. but were able to receive incoming calls.
Kaua‘i Fire Department received a call of a reported fire at the KIUC Port Allen plant at 5:19 p.m. Firefighters reported workers had the flash incident under control.
Kaua‘i Police Department assistant chief Ale Quibilan handled traffic control and regularly updated the dispatch center on situations around the island. He was also in direct communication with KIUC and the DOT.
“The county communications team relayed information, particularly regarding traffic safety and the use of 911, to the public via local radio stations and the county’s Facebook page, as those were the only means of communication during the outage,” Blane said.
Officers were posted at several major intersections. During times that traffic lights are out, Blane said motorists are urged to stay off the roadways whenever possible and to treat all intersections as four-way stops.
