TVA Rep Updates Energy Authority On Christmas Blackouts

A representative from the Tennessee Valley Authority attended the Greeneville Energy Authority board meeting on Monday to provide the governing board of Greeneville Light & Power System more information about the rolling blackouts that affected Greene County over the Christmas weekend in 2022.

As an arctic air mass plunged temperatures in Greene County and much of the southeast into the single digits and near zero degrees for multiple days over the Christmas weekend, the Tennessee Valley Authority instituted rolling blackouts in all of the local utilities it powers, including Greeneville Light & Power System.

A press release from TVA in December said that the blackouts were ordered to keep the power grid stable during the high energy demand as people tried to keep their homes warm in the low temperatures.

According to GLPS President and CEO Chuck Bowlin, keeping the power grid stable is imperative in the "real-time system that TVA operates in."

"As power load and demand comes on, TVA has to react and adjust their power generation output in real time. If load gets too high it starts collapsing that generation. The generators can't keep up with the high load frequency in real time, and it bogs them down. They are programmed to shut down if that occurs to avoid damaging them, and if you lose one then it snowballs because then you have even less generators trying to keep up with the same high load," Bowlin said in December. "So we have to shed load or the whole power system could cascade down and cause widespread, prolonged outages."

It was to avoid those cascading shutdowns that TVA instituted rolling blackouts in its 153 utilities as power demand reached all-time highs over the Christmas weekend.

Chris Quillen, a TVA Regional Relations official, spoke to the board about what caused the TVA to institute blackouts, and what kinds of power plants failed during the severe weather.

Quillen referred to the storm as "Winter Storm Elliot," and said it was the only time the TVA had ordered blackouts to curtail power load in its 89-year history.

"Hopefully that is the last time in my career, and hopefully ever, that we have to do that," Quillen said.

The TVA followed what Quillen called a six-step plan that consists of steps that go in increments of 10, from 10 up to 60.

"Step 60 is when TVA starts cutting power from delivery points. Recovery from that is difficult. You can be cutting 40% of the load sometimes. Step 60 is like what happened in Texas a couple years ago that led to outages for weeks," Quillen said.

Step 50 was reached by TVA, which led to general controlled blackouts across the Southeast to lower load.

"We apologize for getting there to step 50, but thank you for what you all did to handle that and keep us from going to step 60," Quillen said.

Quillen said that when power load changes, TVA's system operators have 15 to 30 minutes to react to adjust to meet demand. Operators either generate more power, purchase power from a neighboring power company or shut down load.

Quillen said that the only option left to TVA was to curtail load due to the manner of the weather.

According to Quillen, the extremely cold temperatures caused power load to dramatically increase, the large geographic scope of the storm affected TVA's neighboring power-producing companies and therefore TVA could not purchase power from them, and the cold temperatures and high wind caused some TVA power plants to go offline.

"Those three things resulted in us having to ask customers to curtail our load," Quillen said. "Everyone else was in the same position as we were, so the option of buying more power was off the table."

Quillen said that coal plants and combined cycle gas plants were the type of power generators that went down during the arctic blast. Quillen specifically mentioned that the two coal-powered 1,200-megawatt generators at the Cumberland Fossil Plant malfunctioned and ceased generation.

"Conditions created unanticipated impacts to generation, transmission, distribution and water systems. Folks had to go out with blow torches and heaters to put some heat on some of the sensors and systems that were freezing up in the weather," Quillen said. "A power plant is sort of like your car these days. It only takes one part to go bad for it to go down, and you then you can't get somewhere. All it takes is on of those sensors, devices or systems to go down and you lose that generation."

Quillen mentioned that frozen sensors and control systems were the culprit of nearly all of the power plant shutdowns that occurred. It was also noted that boilers at the coal power plants were exposed to the atmosphere and froze due to the cold. Quillen said low natural gas pressure "only accounted for a handful" of issues.

"Stuff freezing up is basically the story of these shutdowns," Quillen said.

Quillen noted one of the coal generators at the Cumberland site is set to be replaced with a natural gas combined cycle generator.

"TVA has a long-term plan to get out of the coal power generation business altogether," Quillen said. "Right now, 2035 is the target date to retire all of our coal generation. However, we are not going to retire a plant until we have something on the ground available, capacity-wise, to replace that."

According to Quillen, TVA is reviewing the event closely, and has already identified 200 action steps to be taken by the end of January. The power producer is also taking steps to shore up plants against future severe weather.

"We have a lot of folks looking at this event from all sorts of different angles. We are getting feedback and looking at implementing long-term plans for the future," Quillen said. "Hopefully this ends up being like a really nice spare tire that gets put in the trunk and never gets used again."

OTHER BUSINESS

Bowlin informed the board the power system's allotment of TVA Community Care funding had been distributed.

The Boys & Girls Club of Greeneville and Greene County received $7,000, Greene County United Way received $5,000, Greeneville-Greene County Community Ministries received $5,000 and the Child Advocacy Center of the 3rd Judicial District received $5,000.

The board also voted to take part in TVA's Home Uplift program.

Through the program, TVA will match funds that GLPS provides to customers to make energy upgrades to their homes.

Customers whose income qualifies them for the program will have an application made available to them. TVA administers the program and evaluates the applications.

The Energy Authority board approved $10,000 to go toward the program, which will be matched dollar for dollar by TVA, for a total of $20,000.

The Energy Authority board also held a moment of silence and remembrance for former board member Sam Miller, who served on the board for 31 years before leaving it in 2022. Miller passed away earlier in January.

"He was dedicated to this board. He loved being on it, and he served it well. He was a valuable member of this board," board member Jim Emory said.

"He was a pillar of the community. Everywhere you looked he was doing something for this community," board member Tim Teague said.