McMinnville Electric: Generating Power In Hopes of Clean Energy

McMinnville Electric has been ‘keeping the lights on’ for 70 years and has its hopes set on cleaner renewable energy for the future.

The Tennessee Valley Authority never thought McMinnville Electric System would be able to run a 1.6 megawatt generator on biodiesel with an equal efficiency and output as petroleum.
But Rodney Boyd, CEO and General Manager of McMinnville Electric System, took them up on the challenge. The biodiesel generator actually ran better.

The result was a “triple wow,” said Boyd of the accomplishment with this small power distribution system tucked in the Tennessee valley.

“At 1000 hours of operation, the engine did not show any signs of wear while running at top capacity,” Boyd said.

Using a 3516B Caterpillar generator, McMinnville Electric generated 1,629,024 kWhs of renewable electric power using 124,000 gallons of soybean-based, American-made biodiesel as fuel during a test run of about 1,000 operating hours.

Biodiesel is a renewable fuel made from soybean oil that burns cleaner and reduces the risk to human health and to the environment that one would see with petroleum diesel. 
McMinnville set a precedent by becoming the first municipal utility company in America to run a biodiesel generator at such capacity.

The accomplishment was part of a 2001, $982,000 grant from the U.S. Dept. of Energy, in which McMinnville coordinated the operations and testing with the help of EmeraChem, Stowers/Caterpillar, the Tennessee Valley Authority (TVA), the National BioDiesel Board (NBB), the American Public Power Association (APPA), Agri-Energy, and the Tennessee Soybean Grower’s Association.
The project had its share of challenges, Boyd said.

One was reducing the amount of nitrogen oxides (NOx) emissions. In its quest toward clean energy, Boyd said they achieved a 96.6 percent NOx reduction, verified by the TVA.  The generating process reforms biodiesel into hydrogen, thereby eliminating the ammonia and urea pollutants associated with petroleum.

Petroleum diesel is easily recognizable by the dark fumes it gives off, but Boyd said when the generator ran on biodiesel, the blue sky remained crystal clear.
“You can’t tell it’s running. You can only hear it,” he said.

The project, however, stalled when it was tripped up by a little $1 fuel filter that burned a hole in the NOx trap (plasma reformer). It was rebuilt, but did not return to normal operation.
“The bad news is we were never able to sustain our (NOx) reduction numbers over a long period of time,” Boyd said.

The equipment is being rebuilt and the biodiesel generator now acts as backup to the existing 11 generators at McMinnville. The generator can run independently of the plasma reformer.
Because McMinnville Electric is a TVA distributor, Boyd can’t generate the power for himself. He can only sell it back to TVA, and they do not recognize biodiesel as a “green” source. Only solar, wind, and landfill gas is considered clean energy by TVA. This is because the use of biodiesel for electric generation has not been included as a qualifying resource in any proposed, national Renewable Energy Portfolio Standards legislation.

It is frustrating having it just sit, Boyd said. He hopes TVA, who McMinnville Electric System generates power for, will help get the biodiesel generator development back on track and make it work.

“I know the process and the technology it takes. And probably with additional funding we could pick it back up,” Boyd said, adding that the burned plasma reformer needs to be repaired first.
Interest is picking up recently, and Caterpillar flew some interested parties in from Argentina so Boyd could run the generator for them to see.

“It’s just about getting the word out,” he said. “Since the time we started on that project, the National Biodiesel Board meeting has just exploded. There’s much more interest now.”
Boyd is proud of his work with the biodiesel project, which he petitioned for shortly after joining the company in 2000 as general manager. Before heading to McMinnville Electric, Boyd worked with a north Georgia electric co-op for 21 years, part of which time he earned his master’s degree in business.

McMinnville Electric celebrated its 70th birthday in 2009 and Boyd said the company prides itself on “keeping the lights on.”
Reliability is one of the company’s strongest suits.

“What we’re known for is being able to weather storms,” he said, noting that he soon discovered something unique about McMinnville Electric after he came to work for them.

Boyd recalled coming into work to handle the phone calls during a bad snow storm that hit the region.

“It snowed from that night until 2 p.m. the next day and we didn’t get a single call,” he said. “I knew it was a good system and well-maintained but I didn’t know it was that good.”

Boyd commended his staff, some of which have been with the company for more than 30 years, for maintaining the company’s reliability.

The American Public Power Association (APPA) rated McMinnville Electric in the top 5 percent in the nation in reliability for its size company. McMinnville has 31 employees and an annual electric sales revenue of $20 million.

The state of the economy has hit the central Tennessee valley hard, Boyd said. The region is not seeing a lot of industrial growth, and the company’s Enhanced Growth Credit program is not seeing a lot of action.
The program acts as an economic development tool by providing substantial credits on power bills for companies that move to the Tennessee valley or expand.
But big companies are leaving and job growth is down.

“Since I’ve been here, we’ve lost seven megawatts of industrial load,” Boyd said. “Folks that come in don’t use as much electricity as the ones that leave.”

Boyd sees an improvement coming soon, but mostly on the residential side. He also stresses that the company’s focus for the future is attracting the attention of data centers. Some are looking, Boyd said. A telephone co-op right next to McMinnville Electric has some of the highest networking speeds available in the Southeastern region.

“If you couple light speed Internet capability with reliability, it’s a natural fit for a data center to come in,” he said.

Boyd added that McMinnville Electric is especially attractive because it is centrally located in the state, between two major highways, an hour from two major airports, and two hours from Knoxville.
Along with commercial growth, Boyd has great expectations for green energy in years to come.

His goal is to get the biodiesel generator back on its feet and let the blue sky shine.
Green energy produced 24 hours a day is within sight, he said.

 “Hopefully we can pick back up on the biodiesel project and count that as a success,” Boyd said. ELT