PUCO report criticizes AEP communication, tree trimming after summer outages

The Public Utility Commission of Ohio has issued a report on a series of power outages last summer. Those outages stemmed from a massive windstorm known as a derecho followed by a heat wave with 90+ degree temperatures. Outages occurred throughout the state, but fell heaviest on communities in Columbus, many of them poor.

The report offers critiques of AEP Ohio’s preparation for, and communication during the event, but largely gives the company a pass. Meanwhile, the Ohio Consumers Counsel says further investigation is necessary.

The OCC requested such an investigation in July alongside the Ohio Poverty Law Center and Pro Seniors. AEP opposed that request, and the PUCO never granted it.

“Energy justice for hundreds of thousands of AEP consumers who lost their electricity should be served with a process that is transparent and inclusive of the public and their representatives,” OCC spokesperson Marilee Embs said in a statement.

The system

PUCO staff describe an electrical system where AEP Ohio controls distribution to 1.5 million end users, and another organization, PJM, oversees the operation of major transmission lines. That transmission system operates at the regional level like a wholesaler, while a company like AEP delivers electricity at the retail level to keep your lights on and your AC running.

Because PJM has to maintain electricity across a broad, multi-state territory, it can direct distributors to shed load — shut off power — when demand exceeds capacity. The report describes how a series of those orders forced AEP to cut power. In all, 605,733 customers lost power around the state. More than half of those outages occurred in Columbus.

The outages

The derecho roared through Ohio with winds that reached 80 mph in places. A little before 2:00 pm on June 14, four major transmission lines near Columbus went down. When that happens the system automatically diverts power demand to other lines.

Not long after two more transmission lines went down.

Shifting that much capacity risked further damaging the system. PJM ordered AEP to cut a total of 396 megawatts of power. The report notes AEP uses “software and manual intervention” under those circumstances. When they make decisions manually, AEP shuts down the fewest number of distribution feeds to achieve the reduction demands.

But the report noted, “the number of customers, the type of customers (residential, commercial, or industrial), and the specific location of the customers are not readily available to the operations team and are not considered. The only criterion for selecting those feeds is the amount of load they are carrying.”

That night and into the next day, excessive heat drove further shutdowns. As AEP brought customers back online, the demands on the grid only grew.

“All of their AC units turn on shortly after the power comes on,” the report explained, “and they run continuously for longer-than-usual periods because it takes time to reduce the temperature down to the level set on the thermostat.”

During this second event, PJM ordered AEP to cut 170 megawatts.

Overnight, demand decreased and workers restored lines. By 9:48 am on June 15, the report states, “all customers affected by load shed Events 1 and 2 were restored.”

Less than an hour later, four transmission lines failed again. Three of them were lines that went down the previous day. This time, AEP had to cut 479 megawatts, plunging many of the same customers into darkness.

“Although the new set of substations that required load shedding were not the same group as before, substations in Event 3 were also part of Event 1 and 2,” the report states.

Recommendations and reactions

In its analysis, the report goes through AEP’s emergency plans, maintenance, and inspection record, as well as investments. In general, the report uncovered no glaring errors, but staffers did criticize AEP’s communication to customers and its tree-trimming program.

“Most of the outages were ultimately caused by vegetation coming into contact with the power lines,” the report states. The authors cited examples of “grow-in” outages where, for instance, a branch still connected to a tree damaged a line.

“If the trees were in a position that allowed the storm to alter them to the point that they caused a grow-in outage, then perhaps they had not been trimmed enough,” the report argued. PUCO “recommends” AEP file updated plans within 90 days.

The OCC singled out the report’s handling of tree trimming as a shortcoming.

“While we appreciate today’s PUCO report,” spokesperson Merrilee Embs wrote in a statement, “it begs questions including why there would be outages from electric wires damaged by trees considering the money that AEP charges consumers for tree-trimming.”

The report also urges AEP to develop better plans for communicating with customers. In particular, they point to the utility’s existing, opt-in text message program. “Providing that same service on an opt-out basis may be a way to improve communication,” the report offers. It also notes the utility should consider other options for getting in touch with those without power.

AEP spokesman Scott Blake defended the utility’s conduct during and after the outages.

“Our response over the last few months has been to more aggressively trim trees, do more inspections of our electric lines using advanced imaging technology, and meet with members of the most impacted communities to understand how we can better meet their expectations of us,” Blake said.

“We have trimmed back hundreds of miles of vegetation,” he added, “fixed any damage or hazards we discovered, and are developing stronger relationships our community partners.”

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This story was republished from the Ohio Capital Journal under a Creative Commons license.