The Scoop on Poop

Ethanol has gotten a bad rap in recent years, blamed for guzzling too much energy and grain. But a Baylor University scientist has a recipe for redeeming the fuel’s environmental credibility: Run that grain through a cow first.

Dr. Larry Lehr (pictured, with a jar of ethanol), a lecturer in environmental science, is part of a Waco start-up business that is developing a prototype for an on-farm manure distillery that could allow dairy farmers to turn pollution into profit.

Lehr’s company, Environmental Quality Management Associates (EQMA), is preparing to team with the Texas AgriLife Research and Extension Center in Stephenville to build a model of the manure-to-ethanol system next door to a model dairy that Tarleton State University is building.

EQMA’s project will be designed to turn the manure from the dairy’s four hundred cows into pure ethanol that can be blended with gasoline as fuel. Unlike conventional ethanol, it would require no fossil fuels to produce. The distillery would run on methane gas that has been converted from cow manure. The checklist of earth-friendly features goes on: The byproduct of the distillations would include concentrated nitrogen and phosphorus fertilizer, which could be packaged and sold. And carbon dioxide emissions from the process might even be used to grow algae that could be turned into biofuel.

Lehr said his goal is to find an economical solution to manure pollution, which has plagued the dairy industry for years, especially in North-Central Texas.

“The focus is not particularly on alcohol fuels,” he said. “It’s a pollution remediation project. What’s the value of clean water, or of a dairy farmer being able to increase herd size and decrease pollution?”

Lehr said the model system will eventually be donated to the state, and his firm isn’t making money from it. But he and his partners aim to use the research to develop engineered systems that farmers can buy to process their manure for fuel, rather than storing it in lagoons or spreading it on fields where it could run off into streams.

“If this is successful on a macro-scale, we’ve got commitments for sixty plants,” Lehr said. “Once we get this done, farmers can assess the validity of the project.”

Lehr’s partners include Norm Burgess, a former engineer at Waco’s Mars Snackfoods U.S. plant. They have won a $250,000 grant from the Texas Emerging Technology Fund for manure-to-ethanol research, and they are seeking another $750,000 from the same fund to build the model system.

The plant’s location is strategic; Stephenville is in Erath County, the center of the state’s most productive dairy region. Though the county is some eighty miles northwest of Waco, its dairy farms drain into the North Bosque River, which feeds Lake Waco. Waco city leaders have long blamed the dairies’ phosphorus-rich runoff for causing algae blooms in Lake Waco that make Waco water taste bad. The state has imposed stricter standards on dairies in the North Bosque watershed, and dairy owners have complained that the restrictions make it difficult to expand their herds.

If the ethanol technology is successful and widely adopted, it could solve some of those problems, said Dr. Don Cawthon, resident director of the Texas AgriLife Center in Stephenville and dean of Tarleton’s College of Agriculture and Human Sciences.

“We’re hoping to resolve some of the environmental issues in the Bosque River area, and beyond that to all concentrated animal feeding operations nation-wide, by diverting all the animal waste out of the watershed and converting it into energy,” he said. “The second outcome could be helping achieve the president’s energy plan to convert 25 percent of our energy to renewable energy.”

EQMA officials say the technology would work most efficiently at a large-scale dairy with more than three thousand cows. The average dairy cow produces eighty pounds of manure a day, of which 80 percent is liquid. A dairy’s average waste disposal cost for each cow is around 30 cents per day, Lehr said.

The EQMA process would have costs, too, including labor, but Lehr believes it could yield a net profit. For each ton of manure solids, the process could create forty-five to sixty gallons of ethanol, he said.

Cawthon said the technology EQMA is using at the manure-to-ethanol project in Stephenville may have to be refined and adapted, but that’s the point of the project. “This is the perfect start to the research and development process to move the technology forward,” he said.