Halifax County family's 'beast' is an innovative and efficient tobacco curing system
These wood stumps (left) will soon be fuel in the tobacco-curing boiler's furnace (in background).
Photo by Suzanne Stanard
On this steamy first day of June, the tobacco plants in Halifax County are barely knee-high. They'll be ready for harvest by mid-July, but brothers Robert and Patrick Edwards can't wait for curing season. They're eager to put "the beast" to the test for a second time.
This is their nickname for the enormous - yes, beastly - 125,000-gallon wood-fired boiler they built to cure tobacco. It ran a system of 33 barns last summer.
Wood-burning boilers are nothing new to the world of tobacco curing. But, the enormous scale of the Edwardses' system makes it unique. The largest in the United States, the brothers say.
The best part, they add, is that this boiler is fueled entirely by wood waste, slashing the farm's fuel costs by 85 percent. Logs, wood mill scraps and even whole stumps are burned. Whether picked up by the farm or delivered to them, all of the wood is "trash" that otherwise would end up in landfills. And it's practically free.
"Nothing out there was cut for the purpose of our curing," Robert says, looking out over an expanse of wood piled up behind the boiler. "We also might be eligible for carbon credits, since we're using renewable energy. This machine is clean-burning. There's no smoke."
For their innovation, the Edwards family was named the 2007 Tobacco Growers Association of North Carolina Farm Family of the Year.
Robert, Patrick and their father, Wayne, graduated from the College of Agriculture and Life Sciences with bachelor's degrees in agronomy in 1998, 2002 and 1967, respectively. Patrick also earned a master's degree in crop science in 2005.
After a stint with North Carolina Cooperative Extension, Wayne started the family farm in 1973, working 20 acres of tobacco in Nash County. In 1978, he and his wife, Gaye, moved their family (three sons and a daughter) to a 325-acre farm in southern Halifax County.
Today, their operation spans 660 acres of tobacco, 1,300 acres of cotton, 500 acres of corn and 500 acres of soybeans. They also grow cucumbers and run a cow-calf herd.
At a meeting in late 2005, Patrick ran into Dr. Mike Boyette, CALS professor of biological and agricultural engineering. Boyette had been one of Patrick's professors and had served on his graduate school committee. At the time, the Edwardses were spending about $250,000 a year on natural gas to cure their tobacco. The family wanted an alternative, and the meeting with Boyette turned out to be serendipitous.
Boyette connected the brothers with a designer, Troy Pope, and a builder, Richard Berry, who had worked with small wood-curing systems.
"We wanted a system large enough to handle the wood without us having to process it, and they helped make it happen," Patrick says.
Boyette and Grant Ellington, also of the Department of Biological and Agricultural Engineering, fine-tuned the system along the way.
In summer 2006, the Edwardses cranked up "the beast" for the first time. It worked better than they'd imagined.
The boiler's furnace, shaped like a half-cylinder shell, sits on top of an 18-by-20-foot fire pit that's about six feet deep. Set on bearings, the shell can be rolled back to allow wood to be loaded into the pit.
Water in the shell is heated by the pit boiler, then transferred to a nearby storage tank that pumps it into the barns through a series of insulated mainline pipes. Radiators in the barns extract the heat, then pump the cool water out to be re-heated.
This process runs non-stop for about twelve weeks.
"I remember thinking to myself that if this works, it'll be the best thing since sliced bread," Boyette says. "I was skeptical when we pulled up to the farm to see the boiler in action for the first time. But when we left a couple of hours later, I was convinced that it was a breakthrough."
In fact, the system was so clean-burning that, at first look, Boyette and Ellington couldn't tell that it was running.
The system burns about 50,000 pounds of wood waste a day during curing. It's fed twice a day so that the fire is never extinguished. In only half a curing season last year, the family estimates that they saved $60,000.
What's next? Keep expanding, the brothers say.
"We'll run 34 barns this season," Patrick says. "Eventually, we think we could run 50."
Robert adds, "Last year, it's like we had a car with no accessories. So this year, we're going to tweak it, to make it better."
The family applied for a USDA energy efficiency grant to help offset the cost of improvements. And Boyette will continue to work with them.
"We'll install instrumentation that will allow the boiler to be more energy efficient and run with a lot less hands-on involvement," Boyette says. "We're thinking about placing a wireless link from the boiler up to the house, so they'll know how hot it is without having to go down there in the middle of the night to check."
"There is no burner anywhere I know of that performs like this one," he adds. "It's totally unique. These folks are real innovators."
-Suzanne Stanard
This is their nickname for the enormous - yes, beastly - 125,000-gallon wood-fired boiler they built to cure tobacco. It ran a system of 33 barns last summer.
Wood-burning boilers are nothing new to the world of tobacco curing. But, the enormous scale of the Edwardses' system makes it unique. The largest in the United States, the brothers say.
The best part, they add, is that this boiler is fueled entirely by wood waste, slashing the farm's fuel costs by 85 percent. Logs, wood mill scraps and even whole stumps are burned. Whether picked up by the farm or delivered to them, all of the wood is "trash" that otherwise would end up in landfills. And it's practically free.
"Nothing out there was cut for the purpose of our curing," Robert says, looking out over an expanse of wood piled up behind the boiler. "We also might be eligible for carbon credits, since we're using renewable energy. This machine is clean-burning. There's no smoke."
Robert and Patrick Edwards built this innovative system.
Photo by Suzanne Stanard
Photo by Suzanne Stanard
Robert, Patrick and their father, Wayne, graduated from the College of Agriculture and Life Sciences with bachelor's degrees in agronomy in 1998, 2002 and 1967, respectively. Patrick also earned a master's degree in crop science in 2005.
After a stint with North Carolina Cooperative Extension, Wayne started the family farm in 1973, working 20 acres of tobacco in Nash County. In 1978, he and his wife, Gaye, moved their family (three sons and a daughter) to a 325-acre farm in southern Halifax County.
Today, their operation spans 660 acres of tobacco, 1,300 acres of cotton, 500 acres of corn and 500 acres of soybeans. They also grow cucumbers and run a cow-calf herd.
At a meeting in late 2005, Patrick ran into Dr. Mike Boyette, CALS professor of biological and agricultural engineering. Boyette had been one of Patrick's professors and had served on his graduate school committee. At the time, the Edwardses were spending about $250,000 a year on natural gas to cure their tobacco. The family wanted an alternative, and the meeting with Boyette turned out to be serendipitous.
Boyette connected the brothers with a designer, Troy Pope, and a builder, Richard Berry, who had worked with small wood-curing systems.
"We wanted a system large enough to handle the wood without us having to process it, and they helped make it happen," Patrick says.
Boyette and Grant Ellington, also of the Department of Biological and Agricultural Engineering, fine-tuned the system along the way.
In summer 2006, the Edwardses cranked up "the beast" for the first time. It worked better than they'd imagined.
The boiler's furnace, shaped like a half-cylinder shell, sits on top of an 18-by-20-foot fire pit that's about six feet deep. Set on bearings, the shell can be rolled back to allow wood to be loaded into the pit.
Water in the shell is heated by the pit boiler, then transferred to a nearby storage tank that pumps it into the barns through a series of insulated mainline pipes. Radiators in the barns extract the heat, then pump the cool water out to be re-heated.
This process runs non-stop for about twelve weeks.
"I remember thinking to myself that if this works, it'll be the best thing since sliced bread," Boyette says. "I was skeptical when we pulled up to the farm to see the boiler in action for the first time. But when we left a couple of hours later, I was convinced that it was a breakthrough."
In fact, the system was so clean-burning that, at first look, Boyette and Ellington couldn't tell that it was running.
The system burns about 50,000 pounds of wood waste a day during curing. It's fed twice a day so that the fire is never extinguished. In only half a curing season last year, the family estimates that they saved $60,000.
What's next? Keep expanding, the brothers say.
"We'll run 34 barns this season," Patrick says. "Eventually, we think we could run 50."
Robert adds, "Last year, it's like we had a car with no accessories. So this year, we're going to tweak it, to make it better."
The family applied for a USDA energy efficiency grant to help offset the cost of improvements. And Boyette will continue to work with them.
"We'll install instrumentation that will allow the boiler to be more energy efficient and run with a lot less hands-on involvement," Boyette says. "We're thinking about placing a wireless link from the boiler up to the house, so they'll know how hot it is without having to go down there in the middle of the night to check."
"There is no burner anywhere I know of that performs like this one," he adds. "It's totally unique. These folks are real innovators."
-Suzanne Stanard