VOL. 128 | NO. 214 | Friday, November 01, 2013
Covington Biomass Gasification Plant Online
By Bill Dries
Covington, Tenn., Mayor David Gordon describes himself as a “confirmed nerd” who enjoys reading scientific papers.
Covington Mayor David Gordon and PHG Energy president Tom Stanzione began talking about a plant to use wood and other waste to gasify as fuel for the city’s sewer plant three years ago. The plant has been open for three months.
(Daily News/Bill Dries)
He’s also a Doctor of Veterinary Medicine and holds a Bachelor of Science in biology and chemistry from the University of Tennessee at Martin.
Three years ago at a meeting of the Tennessee Renewable Energy and Economic Development Council, a presentation on biomass gasification got his attention.
Three years later, after Gordon delved further into the details and spreadsheets from PHG Energy of Nashville, Covington has a $2.25 million gasification plant that with wood waste and sludge will produce electricity to run Covington’s sewage plant.
The agreement was announced in July 2012. The gasification plant next to Covington’s wastewater treatment plant has been running for about three months and is now running consistently.
The Covington plant is a $2.25 million project that includes a $250,000 grant from the Tennessee Department of Environment and Conservation and $2 million of Tennessee Municipal Bond fund financing through a general obligation bond issue.
And $3.5 million in savings to the city from that electricity will fund development of an 86-acre expansion of the city’s Cobb Parr Park, west of U.S. 51.
“I think it sets Covington apart as far as a leader in green energy and helping the environment,” Gordon said Wednesday, Oct. 30, before a formal ceremony in the park to signal the opening of the plant.
But Tom Stanzione, president of PHG, said Gordon was not an easy sale on the concept whose only motive was being “green.”
“Ultimately we found the mayor had been looking at a competitor of ours and was not exactly excited about what he was seeing,” Stanzione said.
So he and other PHG executives showed Gordon their biomass gasification plant in Gleason, Tenn., which Stanzione said is a critical part of the effort to get local leaders to understand the business.
Stanzione said Gordon isn’t the only local leader they’ve talked with who had some initial skepticism until he saw the plant in Gleason working.
“We’ve had to do a tremendous amount of education. Gasification kind of got a black eye back in the ’70s and ’80s,” he said. “There were a lot of large-scale attempts at gasification that did not go well. It wasn’t gasification’s fault. It was some of the projects that were attempted were just kind of out of the question for the type of technology.”
Memphis Light, Gas and Water Division planned a coal gasification plant in the 1970s and bought a gas field in Monroe, La., – both of which the utility abandoned in the 1980s. Among the criticisms of the move to gasification then was that MLGW was attempting a commercial-size facility when demonstration plants were needed to fill gaps in data about what the technology could and could not do.
PHG dutifully responded as Gordon continually requested more information and more spreadsheets on the operation of the plant.
“This could not just be a warm fuzzy feeling for me because I am the steward of the citizens’ money. It had to be financially reasonable. It had to be a return on our investment,” Gordon said. “We couldn’t lose money and if we made money that would be great, which we will.”
Gordon questioned the initial spreadsheets, which he said were “very conservative” in terms of the financial side of the equation. They didn’t include the financial impact of “biochar,” which is a result of the process that is similar to activated charcoal and is a marketable product.
The city of Covington bought the 84 acres next to Cobb Parr Park in 2007 on the eve of the global recession and the $3.5 million in savings from the plant goes specifically to developing that acreage as a larger park.
Stanzione and PHG executives repeatedly explained Wednesday at the gathering, which drew leaders from across West Tennessee, how the gasification process works.
“We’re taking two waste streams. We are taking the wood waste, the sludge waste. We’re converting them to energy but we are doing it through gasification,” said Chris Koczaja, vice president of sales and engineering for PHG. “It’s as simply put as adding heat to it but not giving oxygen. We are not incinerating it. We’re not burning it. We’re breaking it down. By breaking it down into simpler molecules we can turn that into a clean burning gas that we can turn into heat and turn that heat into electricity.”