as a weekly practice I listen to npr and do a little sketch on one of the stories. take a look, you can click on the illustration to make it bigger!
Thursday, April 15, 2010
Turning Chicken Poop Into Power
In a dimly lit chicken house, John Logan stands surrounded by thousands of fluffy, yellow, week-old chicks. They're among 275,000 chickens he raises on his farm in Prentiss, Miss. Every 38 days, he ships off a batch to the chicken processor Tyson Foods.
Every year in the United States, 9 billion chickens are raised and sold for food. Their poop has become a problem for the environment.
Several years ago, Logan noticed the phosphorus content in his groundwater had become too high, because of chicken fecal contamination.
"I said, 'I got to do something,' " the farmer recalls. "I can't be putting this on the ground. Now, I have a river right here. What's to happen when that phosphorus overload washes into the river, which then ends up in the Gulf of Mexico?"
Logan considers himself a conservationist. So he turned to the idea of a manure digester, which is something cattle ranchers have been using to turn cow manure into energy. In the past, chicken manure had been mixed with other manure types and then converted into energy, but it had never been used on its own.
Logan worked with researchers and scientists at Mississippi State University to develop and patent the first successful chicken poop digester.
Now, every day, 4 tons of chicken manure are fed into the digester, which resembles a silo. The poop is heated, then mixed with bacteria, which produces the methane gas that is then converted into energy.
EnlargeCourtesy of Greg Gibson, Mississippi Farm Bureau Federation
A chicken digester on John Logan's farm heats chicken manure and mixes it with bacteria, producing methane gas that is converted into energy.
The Environmental Protection Agency has been promoting the use of manure digesters since 1993. But a complicated patchwork of local, state and federal energy policy rules has discouraged people from using them, according to Chris Voell, an EPA program manager. He says with some changes, "instead of 130 digesters around the country, there could be thousands of digesters."
Congress is also considering a fix to the Federal Clean Water Act, which would affect the way poultry operations deal with chicken manure. Bill Satterfield, executive director of the Delmarva Poultry Industry trade group, says new rules would improve the way chickens are produced.
"The more options that chicken growers have in handling the manure in a proper and environmental manner, the better off they are, and the better off the industry is," he says.
As for Logan, he isn't just raising chickens anymore. He sells digesters through his company Eagle Green Energy. They cost $500,000 each, but Logan says they're worth it because the savings add up.
The month before he started using the digester, he says, his power bill was about $8,000. The next month, it dropped to about $200. And "the next month, I got a small check from the power company," he says.
Logan's operation has even gone global. In addition to four digesters operating in Mississippi, and two others in the works for customers in Maryland and Delaware, Logan is working with companies in Italy, Australia and India.
-excerpt from npr