'Poop to power' program turns pig manure into sustainable energy

Jan 09, 2012 By By John Platt

The nearly 9,000 hogs at Loyd Ray Farms in Yadkin County, N.C., produce 400,000 gallons of manure every week. Since the waste had too high a nitrogen content to be used as fertilizer, owner Loyd Bryant used to pump that waste into a local lagoon, where it released methane, ammonia and "an unholy stink," according to the Los Angeles Times.

But now all of that is going to good use. Thanks to Duke University's new Carbon Offsets Initiative, the 154-acre farm now gets half of its electricity from a new waste-to-fuel system that has also solved the environmental problems caused by the . It reduces emissions from the waste, improves the health of Loyd's hogs, and creates a fertilizer he will use to grow corn, wheat and beans.

According to the Carbon Offsets Initiative website, the waste-to-fuel project "collects methane generated by hog waste and burns it to support the operations of the innovative system and create electricity for use on the farm. The destruction of the methane - a greenhouse gas 21 times more potent than carbon dioxide - creates GHG () offsets, and the renewable energy generated by the system creates renewable energy credits."

The $1.2 million system was the first full-scale offsets project completed in the Carbon Offsets Initiative. It was funded by Duke University, Duke Energy and Google - the university and Google will get carbon offset credits from the system - and was made from off-the-shelf parts and freely available designs.

The system "is not overly complicated and stands to yield many more benefits beyond and environmental protection," Tatjana Vujic, director of the Initiative, told the Times. "Farmers like the idea of using every bit of what comes off their farms. They can manage their waste and save money while doing it."

The system has several components. First, the hog waste is placed in an anaerobic digester, which contains bacteria that consume the manure and release methane gas. The methane is then burned to power a 65-kilowatt microturbine, which generates electricity to power support the entire waste management system and much of the farm's normal operations. After the manure is processed in the digester, liquid waste enters an aeration bin, where it is treated for ammonia and other pollutants. The resulting water can be used for irrigation or for flushing out barns. By the time the system is done, it has met all of North Carolina's environmental standards for reduction of odors and emissions.

"It would sound pretty crazy at one time, but we see it works," Bryant told local station Fox8 in October.

Under North Carolina law, the state's utilities must get 0.07 percent of their electricity from hog waste beginning in 2012 and 0.2 percent by 2018, the same amount it must generate from solar.

Explore further: First-of-a-kind supercritical CO2 turbine

3.5 /5 (13 votes)
add to favorites email to friend print save as pdf

Related Stories

Hog waste producing electricity and carbon offsets

Sep 08, 2011

A pilot waste-to-energy system constructed by Duke University and Duke Energy this week garnered the endorsement of Google Inc., which invests in high-quality carbon offsets from across the nation to fulfill ...

Methane from microbes: a fuel for the future

Dec 10, 2007

Microbes could provide a clean, renewable energy source and use up carbon dioxide in the process, suggested Dr James Chong at a Science Media Centre press briefing today.

Chinese dairy harnesses cow-pat power

Nov 25, 2010

A Chinese dairy farm is installing the world's largest system to turn steaming cow pats into enough electricity to power thousands of homes.

Chicken waste turned to watts

Dec 26, 2009

A Nevada energy developer says it has developed an environmentally clean way of using animal waste from chicken farms across the state to light up homes and offices. Green Energy Solutions wants to convert ...

Does converting cow manure to electricity pay off?

Oct 13, 2011

Studies have estimated that converting manure from the 95 million animal units in the United States would produce renewable energy equal to 8 billion gallons of gasoline, or 1% of the total energy consumption in the nation. ...

Study nixes hog waste alternatives

Mar 08, 2006

A $17.3 million study in North Carolina seeking alternatives to open-air ponds used to treat hog farm waste has ended without success.

Recommended for you

First-of-a-kind supercritical CO2 turbine

7 hours ago

Toshiba Corporation today announced that it will supply a first-of-a-kind supercritical CO2 turbine to a demonstration plant being built in Texas, USA. The plant will be developed by NET Power, LLC, a U.S. venture, together w ...

Drive system saves space and weight in electric cars

Oct 17, 2014

Siemens has developed a solution for integrating an electric car's motor and inverter in a single housing. Until now, the motor and the inverter, which converts the battery's direct current into alternating ...

Dispelling a misconception about Mg-ion batteries

Oct 16, 2014

Lithium (Li)-ion batteries serve us well, powering our laptops, tablets, cell phones and a host of other gadgets and devices. However, for future automotive applications, we will need rechargeable batteries ...

Turning humble seaweed into biofuel

Oct 16, 2014

The sea has long been a source of Norway's riches, whether from cod, farmed salmon or oil. Now one researcher from the Norwegian University of Science and Technology (NTNU) researcher hopes to add seaweed ...

Air Umbrella R&D evolves as shield from pelting rain

Oct 15, 2014

A Chinese R&D team have invented an Air Umbrella which can blast water away from the umbrella's owner. They explain how their invention deflects rain: "Air is everywhere on the earth. The flowing air can ...

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

Shootist
2.9 / 5 (8) Jan 09, 2012
This! Even anti-green me, I can support. Used cooking oil to bio diesel, as well. Neither one are energy sinks. Neither technology on Good Intentions and Unicorn Farts.
Xbw
2.2 / 5 (11) Jan 09, 2012
Shootist, want to borrow my unicorn fart power generator? I ate all my unicorns and sold their hoofs for superglue.
Eric_B
3.3 / 5 (6) Jan 09, 2012
"This! Even anti-green me, I can support."

Actually, it doesn't need your support, thank you.