Shiny classic cars are cool to watch as they rumble by, but you have to wonder where their owners get parts.
The federally owned electric utility company Tennessee Valley Authority has a similar issue. When they need to repair or refurbish a hydro turbine for a 100-year-old dam or an electric motor for a 1970s nuclear plant, they can’t exactly order parts from Amazon.
Components become obsolete or difficult to find.
TVA’s Power Service Shops, in the northwest corner of Alabama, are solving that problem – using 3D printing to make the parts they need.
A team of 300 experienced technicians, engineers, project managers and craftspeople in Muscle Shoals use 3D metal printing technology. The technique is new, but the shops have been cranking out parts for the generating fleet since the 1930s.
The additive manufacturing process deposits material to build the pieces one layer at a time. Union craft employees can mobilize in hours to make an urgently needed part.
“We’re kind of like the emergency room for TVA,” explains Corey Saint, power shops manager.
Today, the horizontal lathe can turn components up to 12 feet in diameter, 50 feet long and as heavy as 120 tons. And the shops are adding a Pietro-Carnaghi vertical turning lathe that’s due to come online this year as part of a $39.9 million investment in the shops, allowing increased turning capacity for parts for TVA’s hydroelectric and nuclear generation.
With a critical 24/7 operation, TVA’s need for parts is ongoing.
The utility’s holdings include three nuclear plants, 29 hydroelectric dams, four fossil plants, nine turbine gas plants and nine solar energy sites with future expansion planned.
The first TVA service shop dates to the 1930s and supported war efforts after Wilson Dam was built, says Saint.
“The original power service shop location is at Wilson Dam,” he says. “That’s known as the ‘U’ Building today. But our current location where we’re at was constructed from ’49 to ’50.”
Expansion continued in 1951. The Muscle Shoals “reservation,” or TVA property, now has three or four shops.
“We’ve got some storage warehouses, too, that we conduct work in from time to time,” Saint adds.
The shops serve the entire generating fleet for TVA.
“We service the coal, gas, hydro and nuclear components to support today’s power generation needs,” says Saint. “We specialize in center-line turbine work while also servicing components of a multitude of areas.”
The shops service components for other government agencies, too, such as the Corps of Engineers Bureau of Reclamation.
“We have crews that go out into the field and remove components and bring them back to the shop,” Saint says. After repairs, the parts go back into the field for reinstallation to “put the megawatts back on the grid,” he says.
“We service all the generating assets,” he says, including motors for TVA’s nuclear plants.
Most of the refurbishment work is done in what TVA calls the “outage season” — slow periods in spring and fall when the power demand is lower because of moderate temperatures.
As many as 700 or 800 employees could be in the power shops during that time to service generating assets. Local apprentice shops train employees to work there.
“We’ve got approximately 350 annual TVA employees counting all our support resources,” says Clarissa McClain, senior strategic communicator for TVA’s South Region. “We flex about 500 contractors.”
“We provide a competitive advantage to TVA by being here,” says Saint. “Our people take pride in working here and you can see the results of that work that goes out of the shop.”
In addition to meeting ever-increasing technology demands, “we have to arm our workforce with the knowledge to conduct safe and error-free work,” Saint adds.
“We’ve been very fortunate with TVA continuing to invest and maintain this asset to be able to service or generate the fleet,” Saint says. “I think it’s a huge cost savings to TVA being able to self-perform work versus having to depend on vendors or OEMs because you just have to get in line.”
Future additions include a laser welder, 3D metal light printer and 10-meter vertical turning lathe to work on parts as large as 50 feet. They know of only four vertical lathes that size in the country.
“Otherwise, you just have to get on a list and wait for your turn to get on a machine of this capacity in the U.S.,” Saint says.
The Impact of Wilson Dam
TVA-owned Wilson Dam in the Shoals has an intriguing history that is part of Alabama lore. TVA acquired the neoclassical-style dam in 1933. The treacherous namesake shoals once blocked navigation on the river.
As strange as it seems today, the whole Shoals area almost became the “Detroit of the South” partly because of its power generating capability.
Construction of Wilson Dam on the Tennessee River began in 1918, one year after the U.S. entered WWI. The federal government built two nitrate plants at the Shoals to make explosives, and the dam would supply the needed electricity.
In 1921, automobile magnate Henry Ford wanted to lease the two federally owned fertilizer plants and Wilson Dam for 99 years. He wanted to buy the city of Muscle Shoals and the dam for $5 million, then build a 75-mile-wide city and major manufacturing hub.
Opponents in Congress and elsewhere were concerned about private control over public resources. Debate continued for years and Ford finally withdrew his proposal in 1924.
President Franklin D. Roosevelt signed the Tennessee Valley Authority Act in 1933 and created the government-owned power company to generate electricity and control rampant flooding. Today, TVA supplies power to 10 million people in the Southeast, primarily in North Alabama and Tennessee.
By the Numbers
TVA’s present service area covers 80,000 square miles in seven states, primarily Tennessee and Alabama. The utility has $12.3 billion in annual revenue and lists $57.7 billion in assets, with more than $19 billion in expansion and improvements planned through 2029.
TVA provides electricity for 153 local power companies, including the roughly 230,000 electric customers of Huntsville Utilities. The others in Alabama are:
- Albertville Municipal Utilities Board
- Arab Electric Cooperative
- Athens Utilities
- Bessemer Electric Service
- Cherokee Electric Cooperative
- Courtland Electric Department
- Cullman Electric Cooperative
- Cullman Power Board
- Decatur Utilities
- Electric Board of Guntersville
- Florence Utilities
- Fort Payne Improvement Authority
- Franklin Electric Cooperative
- Hartselle Utilities
- Joe Wheeler Electric Membership Corp.
- Marshall-DeKalb Electric Cooperative
- Muscle Shoals Electric Board
- North Alabama Electric Cooperative
- Russellville Electric Board
- Sand Mountain Electric Cooperative
- Scottsboro Electric Power Board
- Sheffield Utilities
- Tarrant Electric Department
- Tuscumbia Electricity Department
Deborah Storey is a Huntsville-based freelance contributor to Business Alabama.
This article appears in the June 2025 issue of Business Alabama.
