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Buttoning Up the Winter To-Do List

TVA Teams Finalizing Cold-Weather Readiness Repairs

Jason Forsgren’s shift starts at 5:30 a.m., so it’s still dark on his 14-minute commute.

As Forsgren drives up to TVA’s Kingston Fossil Plant in Harriman, Tennessee, he can see lights glowing on the panels that control the heat trace system, which protects outdoor pipes from freezing.

Some of those lights – the green ones – have been around for years. They tell him that the system is powered up.

But these past few months, TVA team members have installed additional lights – red ones the size of a hamburger.

“It looks like a Christmas tree,” Forsgren, the winterization coordinator at Kingston, said.

The big red lights are part of the most comprehensive cold-weather preparedness overhaul in TVA’s 90-year history – a to-do list of nearly 3,400 items that began earlier this year with the addition of more stringent winterization standards. The work will be completed over the next few weeks.

TVA has invested nearly $123 million in the last three months alone to harden its system and enhance the reliability and resiliency at its coal, gas and hydro plants.

For FY 2024, TVA is committing an additional $120 million above normal funding levels to focus specifically on enhancing the reliability of the generation fleet.  

Bolstering reliability at Kingston, for example, each heat trace light indicates power is flowing all the way to the end of an individual heat trace line.

The new monitoring system lets Forsgren tell – even from his truck before dawn – that the freeze protection system is operating correctly.

“My Christmas tree’s on, so we’re good,” he said.

Thousands of upgrades

Heat trace is a thin, flat rubber cable containing conductive wires that heat up when electricity passes through them. It’s strung alongside pipes and sensitive instruments to help keep them from freezing.

At Kingston alone, TVA has replaced more than 2,000 feet of heat trace – 45 individual lines – along with the insulation that surrounds it.

Heat trace lines at all of TVA’s 17 gas plants and four coal plants have been modernized, accounting for more than 2,600 repairs. The new monitoring lights at some plants are blue rather than red, but they function the same.

TVA has also installed 443 wind breaks and enclosures to protect equipment from cold air. These include everything from heated shelters to tentlike temporary enclosures and heavy plastic butcher curtains like you might see in a walk-in cooler.

Another 339 preventive maintenance tasks have been carried out. These have focused on servicing heaters, staging auxiliary heaters and other emergency response equipment, and installing far more robust desiccant drying systems to protect critical air flow pipes and valves.

“We’re doubling our efforts to remove the moisture from the air,” said Derrick Shaw, a combustion turbine technician at Gallatin Combustion Turbine Plant in Sumner County, Tennessee. “If the air is dry, it will not freeze in temperatures typically experienced in extreme winter weather.”

67-Point Checklist

Each of these repairs and upgrades has been tracked using a system of dashboards. A person responsible and a deadline have been assigned for each one. There have been status update meetings multiple times per week.

Almost all the repairs are already done.

The final items being handled are at Ackerman Combined Cycle Plant in Ackerman, Mississippi, which has been in a planned maintenance outage.

This week, a crew of TVA inspectors began fanning out to sites around the Valley region – armed with a multipage, 67-point assessment checklist – to sign off on the work.

Those inspections are slated to be complete by the first week in January, Norm Flake, TVA’s senior program manager of seasonal readiness, said.

TVA team members designed the inspection system to verify nitty-gritty details, such as whether a seam on the lagging – insulation surrounding the heat trace – is positioned in a way that water could seep in and freeze.

On a plant-by-plant basis, the assessments will pin down critical details.

“Did you turn the knobs and slide the levers of winter readiness in the ways we asked?” Flake said.

Top-To-Bottom

The cold-weather to-do list was compiled earlier this year in “a top-to-bottom, fully detailed assessment of every single one of our systems and plants across our coal and gas fleet,” Allen Clare, TVA vice president for power operations performance improvement, said.

TVA’s winter readiness overhaul has also included updated cold-weather response plans, training and drills, and a more rigorous approach to regular maintenance.

These process improvements will pay dividends far beyond the current winter, Clare said.

Every time equipment is disassembled and reassembled for regular maintenance, it will be checked for even seemingly minor items, such as the insulation seam placement.

“Every year, our plants conduct planned outages, which requires disassembling and reassembling equipment,” Clare said. “Freeze protection is a complex system and, if not properly reassembled, it will not function effectively.

“Proper attention has to be paid to all of these minute details during maintenance activities. We’ve revised our processes and programs and made them more robust.”

Flake said he’s proud of the work by every TVA team member, from the site level all the way to top management.

“To make it right and get it right for our customers and the people of the Valley – it’s what drives us," Flake said.

Photo Gallery

Workers walk across a gravel lot outside Gallatin Combustion Turbine Plant in Sumner County, Tennessee

Howie Rose, left, TVA senior program manager for emergency preparedness response, leads a team inspecting the modernized heat trace system at the Gallatin Combustion Turbine Plant. With him are electrical contractor Rodolfo Morin, center, and TVA inspector Barry McGhee.

A crew of workers meet at Gallatin Combustion Turbine Plant

TVA winterization inspectors will be visiting gas and coal plants across the Valley region between now and the first week of January to verify the upgrades are complete.

Workers inspect equipment at Gallatin Combustion Turbine Plant

Shiny new lagging, the insulation covering heat trace, is inspected to ensure seams face downward. This further prevents moisture from entering the system which can cause issues at freezing temperatures.

A worker explains the winterization work at Gallatin

Norm Flake, TVA senior program manager of seasonal readiness, said inspectors check that freeze protection equipment is assembled correctly after every regular maintenance to ensure it operates as designed.

Red lights on heat trace technology let workers know the system is working properly

A "Christmas tree" of new red heat trace monitoring lights glows before dawn at Kingston Fossil Plant in Harriman, Tennessee. The light is a visual indicator that the heat trace is operational.

Gallatin Combustion Turbine Plant site manager Corey Terry

Plant manager Corey Terry of Gallatin Combustion Turbine Plant in Sumner County, Tennessee, said TVA has built enclosures, modernized heat trace, and taken other steps to prepare the plant for winter.

PHOTO AT TOP OF THE PAGE: TVA inspectors (left to right) Dykie Gentry, Matt Smith and Patrick Wallace go over a 67-point winterization checklist at Gallatin Combustion Turbine Plant in Sumner County, Tennessee.

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