Tennessee Valley power supplies not keeping pace with growth, study says

Power cooperatives worry about more winter power blackouts, but TVA says it has upgraded equipment and resiliency

The Tennessee Valley Authority's Cumberland Fossil Plant near Clarksville, Tenn., is shown in this 2002 photo. The coal plant near Nashville shut off power during Winter Storm Elliott last December when equipment froze at the plant. (AP Photo/TVA, Ron Schmitt)
The Tennessee Valley Authority's Cumberland Fossil Plant near Clarksville, Tenn., is shown in this 2002 photo. The coal plant near Nashville shut off power during Winter Storm Elliott last December when equipment froze at the plant. (AP Photo/TVA, Ron Schmitt)

A year after rolling blackouts hit the Tennessee Valley for the first time, a new study on America's power grid says electricity demand continues to grow faster than new generation, threatening to create more power outages during cold winter days ahead.

"A large portion of the North American bulk power system is at risk of insufficient electricity supplies during peak winter conditions," North American Electric Reliability Corp. said in its newly released 2023-24 Winter Reliability Assessment. "Prolonged, wide-area cold snaps threaten the reliable performance of the generation and the availability of fuel supplies for natural-gas-fired generation."

The nonprofit organization that works to coordinate power deliveries and limit outages said Tennessee and other Mid-South states are among those vulnerable for power interruptions.

Although the Tennessee Valley Authority says it has made its power system most resilient for cold weather, power cooperatives in the Tennessee Valley say they remain worried about more power limitations or rolling blackouts like those that cut TVA power during Winter Storm Elliott last December.

"Under normal conditions, the system is going to be fine," said Jim Matheson, CEO of the National Rural Electric Cooperative Association, the national trade group for nearly 900 local electric cooperatives. "But if you have an extreme weather event like what you saw in Tennessee last year during Winter Storm Elliott, that's when demand exceeds supply. This is an ongoing problem, and the trend is not good because our public policies are forcing decisions that are making the risk of power outages greater and the situation could get even worse going forward."

Matheson, a former U.S. congressman from Utah, said in a telephone interview the rolling blackouts that cut off electricity, at least temporarily, in nine states just before Christmas could happen again under severe weather conditions.

"If there's a cold snap, the risk is there again," Matheson said.

On Dec. 23 and Christmas Eve last year, TVA was forced to limit power deliveries to the 153 local power companies it serves, forcing rolling blackouts for the first time in TVA's 90-year history. A sudden plunge in temperatures and high winds combined to freeze some lines and shut down TVA's biggest coal plant -- the Cumberland Fossil Plant near Nashville -- as well as cut off power delivery from several natural gas power plants owned by TVA and other utilities. Tennessee was among nine states with rolling blackouts last December from the winter storm.

  photo  Staff Photo by Robin Rudd / The Tennessee Valley Authority's Chickamauga Dam is seen behind transmission towers Feb. 16.
 
 

 TVA President Jeff Lyash said the federal utility has upgraded its network and improved insulation for equipment lines and controls at its Cumberland Fossil Plant and other facilities to make them less vulnerable to freezing temperatures and winds.

"Winter Storm Elliott was beyond our winter storm design basis," Lyash said, noting temperatures and high winds combined to push power demand higher and well above forecast levels.

(READ MORE: TVA upgrades equipment to avoid more power blackouts)

Lyash said the system was tested last summer with several power peaks for TVA above 32,000 megawatts "and we were rock solid.

"That's the way we feel about the winter," Lyash said in an interview. "We've got good investments and we've got good plants, so I feel good about the winter. But we won't take our eye off the ball."

Compared with a year earlier, TVA has more solar generation, plus another 1,500 megawatts of natural gas-fired generation to help meet peak demands in power.

"If we had the same conditions as Winter Storm Elliott again, you wouldn't see the same result," Lyash said. "But I'm paranoid about this all the time, and we'll always be concerned about doing everything we can to maintain power reliability."

TVA spokesperson Scott Fiedler said TVA spent more than $8 million to upgrade power connections and lines to the Cumberland Fossil Plant and other equipment at TVA's natural gas plants to ensure they continue to operate under colder and more adverse weather conditions than they have in the past. In the current fiscal year, TVA has budgeted another $35 million for even more improvements in power resiliency.

"We've increased our training and added real-time sensors to our equipment," Fielder said during a news event last week at the Sequoyah Nuclear Plant. "We've also worked with our local power companies on our communications with us to help us get relevant information out to our customers. So going into this winter, we're very confident that we are reliable and we have the power necessary to keep the valley electrified."

TVA has maintained 99.999% reliability in its delivered power to its 153 local power companies for more than 20 consecutive years.

But Lyash concedes that TVA is facing an unprecedented growth in new power demand with the population of the Tennessee Valley growing three times faster than the U.S. as a whole and with more transportation and manufacturing switching from gasoline and other fossil fuels to electricity and batteries for power. TVA projects its power demand could double by 2050, even as TVA prepares to phase out the last of the 59 coal-fired generators it once operated by the year 2035.

"We're seeing a tremendous amount of both residential and industrial growth in Tennessee as well as more electrification of the economy as companies try to meet their carbon reduction goals," Mike Knotts, chief executive of the Tennessee Electric Cooperative Association, said in a telephone interview. "We do have a supply challenge in the Tennessee Valley. We applaud the steps that TVA has taken since Winter Storm Elliott, which was a wake up call for all of us. But this absolutely cannot be repeated."

(READ MORE: Hamilton County grows more than 3 times the US rate last year)

Knotts said power cooperatives in the Tennessee Valley invested more than $200 million this year in maintenance and resiliency upgrades to help ensure that electricity is delivered to the 10 million homes and businesses in TVA's seven-state region.

"But ultimately, this becomes a supply challenge and a question if TVA can keep up with this growing demand," Knotts said. "There is still a risk here (of future outages)."

TVA is adding more natural gas generation and buying more solar power and it is working to build the next generation of nuclear power plants with smaller and more flexible nuclear units than the seven current reactors operating in Tennessee and Alabama. TVA is planning to build 20 or more factory-built small modular reactors across the Tennessee Valley, including the first units near the Oak Ridge National Laboratory in East Tennessee.

But the Nuclear Regulatory Commission has yet to approve the specific design for the new smaller reactors and TVA's board has not yet approved specific construction plans.

Matheson said new greenhouse emission rules by the U.S. Environmental Protection Agency are pushing utilities to try to deploy more carbon capture and hydrogen generation by 2031 even before such technologies are feasible for most power production.

"These rules assume application of technologies that are not even ready and, in our view, violate the Clean Air Act," he said.

Matheson also complained about permitting regulation that make it more difficult and prolonged to build needed gas pipelines, transmission lines and solar generators.

Without a reliable electric grid, clean air and carbon-free strategies using more electrification to replace fossil fuels won't be effective, Matheson said.

"The problem is pretty basic: demand is growing and supply's not keeping up," Matheson said.

Contact Dave Flessner at [email protected] or 423-757-6340.

 
  photo  Keeping electricity on through the winter months could be a challenge again this year during extreme weather in parts of the country, according to a new assessment by the North American Electric Reliability Corp. (Tony Overman/The Olympian/MCT)
 
 

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