MEA, Chugach Electric restore power after Monday outages; cause still being searched

Matanuska Electric Association officials were still searching Tuesday for the exact cause of the widespread power outage that caused members of MEA and Chugach Electric Association to lose service late Monday afternoon.

Something happened to the long-distance Alaska Intertie power transmission line between Wasilla and Talkeetna, an area within MEA’s service area.

Aerial flights were done Tuesday morning to inspect the line but as of noon the source of the disruption could not be pinpointed, said Julie Estey, spokesperson for MEA.

Power was restored after 45 minutes in most of the co-op’s service area, Estey said. It took about an hour and a half for service to be reestablished in Chugach Electric’s customers, which are mostly in Anchorage, according to Julie Hasquet, spokesperson for Chugach.

Some parts of the MEA’s service area was not affected, however. Parts of Palmer, for example, experienced no outage, residents said.

Estey said what was experienced was “load-shedding,” a process automatically triggered when something happens that reduces the ability to transmit power through a transmission line.

By quickly reducing service to selected customers the integrity of the overall grid is protected, preventing a total failure and blackout.

Load-shedding is done on a schedule agreed on ahead of time by utilities to protect the grid. In this case only Chugach and MEA were affected along the interconnected “railbelt” system and not Homer Electric Association on the Kenai Peninsula or Golden Valley Electric Association in Interior Alaska, which are also connected to the “railbelt” Interior-Southcentral power grid.

The sudden power transmission interruption caused some generating units in two of Chugach Electric’s power plants to go down temporarily but other units in the plants continued to function.

MEA’s Eklutna power plant continued to function normally, Estey said. The problem was not in the generating plant but in the transmission system, she said.

Although power outages are annoyances they are not unusual and are typically short-term, as this one was. But however brief, what was unusual about this one was how widespread the outages were. At one point 45,000 customers in the Anchorage area were without power.

The procedure for load-shedding protects critical infrastructure like hospitals and, in Mat-Su, the Goose Bay prison. In Anchorage, service continued at Ted Stevens International Airport and at Joint Base Elmendorf-Richardson.

Chugach and MEA are in the final stages of installing large electrical storage batteries which are jointly-owned. While the primary purpose of these is to even out the flow of power amin minor fluctuations in the system, they will, once installed, provide for some emergency backup against events like what occurred Monday. They are not a total solution, however.

Meanwhile, the outage Monday reminded residents in Mat-Su and Anchorage how dependent modern life has become on a steady supply of electricity, for everything from recharging cell phones and laptops to powering garage door openers.

Also, Alaskans should count themselves lucky to not be experiencing the prolonged outages seen recently in Texas, where thousands of people went for days without power and air conditioning when utility systems went down because of high heat levels.