Pig Poop to Electricity
North Carolina pigs will help generate electricity
DECEMBER 15, 2016 3:37 PM
BY JOHN MURAWSKI
A Colorado energy developer broke ground Thursday on a $100 million facility in Duplin County that the company said will be the largest of its type in the nation, and will produce natural gas out of swine waste and other agricultural byproducts. That facility, and smaller ones already in operation and in planning, could push North Carolina past a swine waste-to-energy goal the state was supposed to have first reached in 2012.
Turning pig poop into natural gas poses technological and economic challenges that have limited such conversion facilities to small projects that burn gas in small on-site generators. The Carbon Cycle Energy project, near Warsaw, will pump the methane through the state’s pipeline system to full-scale power plants owned by Duke Energy. The electric utility company will burn the gas and claim renewables credits to comply with North Carolina’s 2007 renewable energy mandate.
“Meeting those mandates on swine waste has been tough for us,” Duke Spokesman, Randy Wheeless said. “You’ve got to have geography, a fuel source, an off-taker – just a lot of things have to fall into place.”
Jay Lucas, an engineer with the N.C. Public Staff, said the size of the project exceeds all expectations. The Public Staff represents the interests of utility customers before the N.C. Utilities Commission.
“We haven’t come close to meeting it yet,” Lucas said on North Carolina’s renewable mandate for swine waste, “and in one swoop we have a facility to [help the state] meet the whole thing.”
North Carolina was the first state in the Southeast in 2007 to adopt a renewable energy mandate for electric utilities. The vast majority has been fulfilled by solar power, which has turned North Carolina into the nation’s second-largest developer of solar energy farms. The state remains the only one in the nation that requires a portion of electricity to come from energy-rich agricultural resources that remain largely untapped: hog waste and poultry droppings.
Even at a considerable scale that will require 40 employees for the round-the-clock operation, the Carbon Cycle Energy plant will produce only about two-thirds of the amount of swine-sourced natural gas the state will require for its first-year goal.
The Carbon Cycle Energy Project will produce about 290,000 megawatt hours a year when it’s operating at full capacity in 2018, but only about 66,700 megawatt hours will be attributable to swine waste, said company CEO James Powell. Most of the gas the plant will produce will come from poultry waste, animal carcasses and waste scraps from industrial food processing operations.
North Carolina’s first-year goal for swine waste is 0.07 percent of total annual retail electricity sales of each utility, which is equivalent to about about 93,000 megawatt hours of electricity. The target increases year by year and tops out at 0.2 percent, or 270,000 megawatt hours of retail electricity sold annually. Utilities were supposed to meet the first-year goal in 2012 but received five years of consecutive postponements by the Utilities Commission.
North Carolina has eight swine waste-to-energy facilities, the largest of which is in Bladen County and produces a quantity of natural gas that generates an estimated 7,900 megawatt hours of electricity annually, Lucas said. The Carbon Cycle Energy plant will generate more than eight times as much gas from swine waste, and more than 35 times as much waste from all agricultural waste combined.
The plant will source the agricultural waste from more than 25 producers within a 75-mile radius, Powell said.
“There’s just a plethora of organic waste in that region,” he said.