TVA defends storm-racked grid

TVA defends storm-racked grid

June 27th, 2011 by Pam Sohn in News

TVA transmission line crew members Paul White, left, and Paul Walker hook a line to the back of a truck to run a power line near the Widows Creek Coal plant in Stevenson, Ala.

Photo by Tim Barber/Times Free Press.

For 22 straight days before Memorial Day, TVA's Travis Terry and his crew worked 16 to 18 hours a day, unsnarling the electric power grid after tornadoes tied power towers and electric lines in knots.

"In the first six or seven days, we worked 42 hours on, six hours off," Terry said.

After Memorial Day weekend, the crew went back to its grueling schedule. This weekend Terry expected to get the last power grid line back up at the Widow's Creek Fossil Plant in Northeast Alabama.

"We can see the light at the end of the tunnel, and we're tickled to death," he said.

In late April, a record-setting attack of tornadoes took out 108 TVA power transmission lines and 353 of the utility's monster power towers.

In one section of the power transmission right of way near Widows Creek, every line and tower for a little more than a mile was turned into a garbage pile of steel and cable. Fourteen power distributors and 847,000 homes and businesses were totally cut off from TVA power, leaving all of North Alabama and most of Northeast Mississippi in the dark for a week.

The blackout points up what many experts have called the power grid's fragility, and it has some calling for another "beyond design" lesson about energy.

"Our power grid is very vulnerable. It's very much on edge. Our military knows that," said U.S. Rep. Roscoe Bartlett, R-Md.

TVA officials say the grid was storm-racked, not fragile.

But with no power for days on end to run refrigerators, heating and air-conditioning systems and even the reactor cooling systems for Browns Ferry Nuclear Plant, losing a major portion of the electric grid in the Southeast was an eye-opener.

Backups and alternatives

James B. Sandlin, manager of the Scottsboro Electric Power Board, said his city had very little storm damage but was at the mercy of TVA - at least at first.

"I think it was a wake-up call for a lot of people, and we've started marketing home generators," Sandlin said. "But we had begun putting together an alternative plan as a utility several years ago."

Three other events shaped Scottsboro's plan: The snowstorm of 1993; the terrorist attacks of Sept. 11, 2001; and the demise of a major Jackson County manufacturer that left the utility in charge of five giant diesel generators.

When TVA went black, Scottsboro made some quick engineering modifications and used the generators and its cable system to rotate power around town to its 8,500 customers in two- and three-hour daily blocks.

"It made a big difference to a lot of people," Sandlin said.

TVA and electric power generation industry groups don't think the tornado damage to the grid could have been avoided or that it points up problems.

"We do not believe our system is fragile," TVA spokeswoman Barbara Martocci said.

Officials with the Electric Power Research Institute agree.

"It would be almost impossible to build a transmission line that would withstand tornadoes like that - either from the cost-efficiency standpoint or in practical terms," said Andrew Phillips, EPRI's director of transmission and power assets.

Daniel Brooks, EPRI's operations and planning research program manager, said the tornado damage wasn't as much a wake-up call as a reminder of how much people take the normal reliability of electric power for granted.

"The fact that everybody had electricity again in 51/2 days speaks not to the fragility of the system, but I think speaks to the robustness of the system," Brooks said.

Looking ahead

Sandlin said Scottsboro is the only utility in Northeast Alabama with the planning and needed assets to generate its own power, but that can only happen in specific situations, according to the terms of the utility's power contract with TVA.

Those situations usually are to the benefit of TVA - such as helping smooth out peak demand or steady power fluctuations, Sandlin said.

"TVA's contract forbids us to generate our own electricity, but from a policy standpoint, I think the TVA board needs to look at this subject," Sandlin said.

David Orr, a nationally recognized environmentalist and Pentagon climate change consultant who spoke in Chattanooga just after the tornadoes, said terrorism and climate change are dictating new needs for energy policy.

"Anything that is as centralized as our power grid, which takes power from one big place to many small ones, is vulnerable," he said. "We have to change the model."

TVA's Martocci said distributors are allowed to use their own generation to supply power when TVA cannot.

But, she said, "it would be uneconomical for a distributor to keep a large amount of generation on standby for a storm that might happen once every 10 or 20 years."

"We would not rethink this because we are in a contract with distributors to supply their needs. That is how we plan our system and how much power we generate - to meet their loads," she said.

This week and next, Terry and TVA line crew manager Chad Suttles will continue the Herculean task of rebuilding the last six of 108 destroyed transmission lines.

TVA estimates the storms cost the utility - and ratepayers - nearly $200 million, including about $90 million to buy replacement power.

Martocci said TVA's reliability performance measure - 99.999 - will not change because of the storm-forced outages. The performance measure does not count storms because the utility can't control nature, she said.

"If we were to do this [count storms], it could skew those numbers and cause us to work on things that would be too costly to maintain and not focus on the things we can control," she said. "However, we will look at what happened during the storms and determine if there is a need to change anything to lessen our risk and damage."