By Rona Kobell on December 17, 2017
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Glenn Rodes was born and raised on an 860-acre turkey farm in Port Republic, VA, just south of Harrisonburg in the Shenandoah Valley. Four generations of his family live there still, raising turkeys, cattle and row crops. With the Blue Ridge Mountains in the distance; some of the trees look as old as the state itself.

Nelson Rodes stands near his farm’s Bio-Burner, which converts turkey manure into fuel.(Rona Kobell)

Nelson Rodes stands near his farm’s Bio-Burner, which converts turkey manure into fuel.(Rona Kobell)

But while Riverhill Farms may seem unchanged by time, Rodes and his family are looking to the future. They have been experimenting with turning manure into energy for several years. Rodes even calls himself a “fuel farmer” in his email address.

The Rodes farm has a Bio-Burner, a biomass heating system that uses a portion of the manure from the 280,000 turkeys they raise each year to produce heat for their poultry houses and save thousands of dollars annually in propane costs. The burner breaks down the manure into a methane gas that’s used for heat as well as an ash byproduct.

“I thought it was a shame we weren’t producing more of our own energy,” Rodes said one chilly afternoon as he demonstrated the device. “And here we had a product that we could use to do it.”

Advocates for manure-to-energy technology are watching Rodes’ progress. Kristen Hughes, executive director of Sustainable Chesapeake, a nonprofit organization that has been involved with a variety of manure-to-energy demonstration projects, said she’s excited about the progress the Rodes brothers have made in the last several years. Hughes brought her board of directors to the farm recently to see the operation and talk to Rodes about what he’s learned.

“Burning poultry litter is not an easy thing to do,” she said. “We need to make sure that when we look at a new product, we look at it with educated skepticism.”

The Bio-Burner, developed by Kentucky-based LEI Systems, cost Rodes about $100,000, much of which was covered by federal grants. He installed a second system for about $60,000 with his own money. Rodes has tinkered with both systems to optimize them for his farm, both for energy production and environmental performance.

Manure-to-energy technology exists in many variations and at different scales, from the single-farm systems to companies that collect and process manure from various locations. Chesapeake Bay scientists and policymakers have long discussed the potential for such projects to reduce nutrient pollution in the Bay and its rivers. The systems help keep excess manure nutrients out of the waterways while producing energy for farmers.

While renewable energy sources like wind, solar and geothermal all cut down on fossil fuel emissions, only manure-to-energy systems take a pollution problem and convert it into a fuel, said Chesapeake Bay Commission director Ann Pesiri Swanson.

Environmental, technical and financial challenges have slowed widespread adoption, though.

It’s not cheap to burn poultry litter, and no one does it primarily because it’s an efficient way to make energy, said Patrick Thompson, whose company, EnergyWorks, has been turning manure from 5 million egg-laying hens into power and ash products in Gettysburg, PA. The state helped finance the $40 million plant through long-term, low-interest loans, which Thompson is paying back, slowly.

Several entrepreneurs, including Thompson, have been seeking changes to Pennsylvania’s nutrient credit-trading program to make their operations profitable. Such a program would allow projects and businesses that generate nutrient pollution to offset it by purchasing credits from businesses that reduce the amount of nutrients getting into the water.

Maryland, Pennsylvania and Virginia have all put money into subsidizing manure-to-energy pilot projects, and Maryland’s Department of Agriculture has committed nearly $3.8 million so far to companies and farm operations working on various approaches. Part of the push for the technology comes from the state’s new “phosphorus management tool,” a regulation that limits, or even bars, the use of manure to fertilize fields with excessive phosphorus levels in the soil.

Virginia also has a limit on how much phosphorus fields can handle; Rodes exports most of his manure from eight flocks to land outside the Chesapeake Bay watershed, where customers want it for fertilizer. The manure broker pays for the transport.

Some farm-scale energy systems have shown promise, but other projects have stalled, such as the large manure-to-energy system that Colorado-based Bion Environmental Technologies, Inc.installed at a Lancaster County farm. The Bion subsidiary that installed the system is in default on a $7.8 million state loan, and the facility remains shuttered.

Nutrient management concerns are not eliminated by these systems, either. Some generate ash as a byproduct. It is rich in phosphorus, lighter to transport than poultry manure and could be sold as a fertilizer if the market is developed. To meet water quality goals, though, the ash would need to be used in ways that will not create an excess of nutrients in the soil elsewhere and just relocate the problem it was intended to solve. Rodes’ system to date has produced so little of it that he’s given it away to researchers and mixed some in with his fertilizer. But he believes, as do other researchers, that there is a market for the ash product as a fertilizer for tomatoes and other plants.

The air emissions from the burners also contain nutrients, which can fall back to the ground and return to waterways. Early manure-to-energy projects in places like Minnesota seemed to trade one problem for another: Burning the manure reduced excess nutrients going onto fields but increased the levels of phosphorus and nitrogen coming out of the smokestack, resulting in emissions violations.

Rodes is operating under a conditional state permit, which approves the experimental nature of his system and closely monitors its emissions. He believes that alterations to his system, after much trial and error, are helping it become a clean-burning operation. But it is not there yet. Rodes estimates that another year or so of tweaks and testing will be needed to produce emissions low enough to make the system viable for regulators and attractive to farmers.

Ann Jennings, the Chesapeake Bay Commission’s Virginia director, said the visit to Rodes’ Riverhill Farms made clear that there is no “silver bullet” with manure to energy. Whether it works, she said, depends on the farm — and the farmer.

Rodes’ system may not work on every farm, and some farmers may not want to bother with it, especially when conventional fuel, such as propane, is inexpensive. But, Rodes said, they may well change their minds if the price triples. Indeed, after the oil crises in the 1970s, dairy farmers began using a different manure-to-energy process called anaerobic digestion to heat their barns and milking parlors; a few of those systems are still operating. But while digestion works well with wet cattle manure, it’s not efficient for processing poultry manure.

The Chesapeake Bay may be 200 miles from the South Fork of the Shenandoah, but water quality is not far from the Rodes’ minds. That, Jennings said, is inspiring.

“When you see farmers like this who are taking the time and putting in the resources to help the Chesapeake Bay,” she said, “you leave energized.”

(As originally posted, this story misidentified the entity in default of a Pennsylvania state loan for a manure-to-energy system. It is the subsidiary set up by Bion Environmental Technologies, Inc. to install the system, not the parent company itself. The Bay Journal regrets the error.)