At approximately 11:37 a.m. this morning, KEA experienced a power outage from a fault at the Airport Substation, temporarily interrupting power transmission from the Terror Lake hydroelectric facility. All KEA members on Kodiak’s road system were affected, but Port Lions did not lose power.
KEA dispatchers reacted to the situation and stabilized the Kodiak power system. Power was restored to some areas within ten minutes, and all customers were back on line within one hour. Investigation revealed that the outage was caused when an auxiliary piece of equipment in the substation malfunctioned, causing a breaker to trip.
KEA has done extensive work in 2010 and 2011 to upgrade the Airport Substation, in anticipation of installing the third turbine at Terror Lake, and to increase transmission system reliability. Last year, two thirty-year-old 138 KV oil circuit breakers were replaced with new “oil free” SF6 138 KV breakers from Mitsubishi Electric Power Products. By replacing the old breakers with the finest breakers available in the industry, we eliminated 4,800 gallons of oil from our electrical system. We also replaced distribution relays and switches, repaired concrete footers and foundations. This year, we extended existing 138 KV high voltage bus work, and installed a new 30 MVA 138 KV to 69 KV transformer and associated high voltage circuit breakers. The addition of the second 138/69 KV transformer will allow us to utilize the full power production of Terror Lake after the installation of the third hydro turbine, scheduled for fall of 2013.