A covered lagoon helps control odor, while methane will be used to heat barns and generate offset credits.
The future is here and along with it comes an emerging greenhouse gas (GHG) offset, or carbon credit market. Gases captured from hog manure lagoons can now be repurposed or flared to release gases that are no longer harmful to the environment, and are creating offset credit values of about CAN $12.00/tonne (1 tonne = 2,205 lb.) in Alberta, Canada, slightly less in U.S. $ ($11.10).
Alberta is the first jurisdiction in North America to establish a statutory requirement for large final emitters (LFEs) to reduce emissions of GHGs. It is now slapping heavy emitters of carbon dioxide with fines of $15/tonne for above-limit production.
In addition to curbing emissions, the initiative is sparking much greater demand for GHG offsets as LFEs now must comply with the new regulations.
Targeting Odor, Offsets
Starlight Colony Farms, a 600-sow, farrow-to-finish operation near Starbuck, Manitoba, will be ready when their province jumps on the carbon credit bandwagon. While the idea of reducing the colony's carbon footprint played a big role in choosing to participate in the project, barn manager James Hofer says it also seemed a good way to solve concerns about odor, which was creating tension with the neighboring town located only 2½ miles away.
The colony started its hog operation in 1985, using underground concrete storages, which had no odor problem until government regulations changed in 1998. Livestock facilities of over 300 units could no longer spread manure in the winter and were required to have 400-day storage, above ground.
For several years they tried different options, but none gave them the odor control they were looking for. In the end, they used a straw cover — a short-term solution that only ended up adding more solids to the storage.
After two years of deliberations, the colony was able to get a government permit, and a cover made of 60,000 lb. of heavy-duty, low-linear polyethylene was retrofitted on their main 150 × 300-ft. lagoon in June 2009. Weighted down with 65,000 lb. of sandbags and anchored in a compacted trench around the perimeter of the lagoon, the permanent cover is air and water tight. It should even withstand Canada's treacherous winters for a good 10 years or more, Hofer explains.
The lagoon cover is the brainchild of Preferred Carbon, a Calgary-based firm in the carbon business. The company, along with Farmer's Edge, an independent crop consulting company mostly known for their variable rate fertility program, are offering producers ways to create and market their carbon credits.
As gas forms under the cover, it creates a positive pressure that allows it to move through the gas handling system and out to a flare stack, where it is ignited and destroyed. Hofer says they are eventually hoping to run a 2-in. line from the covered lagoon to their coal boiler, about 800 ft. away, and use the gas to heat their barns in the winter.
“There is virtually no smell coming off the (main storage) lagoon,” says Hofer. “In three months, once it becomes fully anaerobic, the discharge coming from the first cell will basically be like fizzed-out Coke; there won't be any punch left to it and there should virtually be no smell at all.”
The site is also close to Winnipeg, home of University of Manitoba, where the engineering department and department of animal sciences are busy gathering data on the amount of GHGs emitted by a lagoon and the impact the cover has on manure management.
“Their research will help us refine the system and improve our understanding of the biological processes occurring in the lagoon, particularly in these colder climates,” says Bruce Love, a director with Preferred Carbon. “Carbon credits are based on GHG baselines of what regulations or standard practices require you to do. Potentially, anything you eliminate in your operation that further reduces GHG emissions could qualify you for a credit, if these numbers can be backed with science in a recognized GHG offset protocol.”
Love and Hofer hope the lagoon cover program never becomes mandatory, however.
“Every country wants to be able to demonstrate that they are reducing their carbon emissions, and the biggest potential for reductions in Manitoba is agriculture,” believes Hofer. “But if you're not going to reward producers or let agriculture get its reward for the environmentally good work that they do, then it's not going to get done.”
Eye on Sustainability
Reducing the carbon footprint is another way of making hog farming sustainable, and Hofer hopes GHG offsets will become part of good production practices, along with the commitment, dedication and sense of pride found with all Canada and Manitoba pork products.
“There is a lot of interest in western Canada right now as the federal government has announced the development of a carbon cap-and-trade system similar to that proposed in the United States, with a significant portion of the offsets coming from the agricultural sector,” says Farmer's Edge agronomist Brunel Sabourin. He cautions, however, that the first sellers in the market normally receive the lowest price and recommends farmers learn a bit about these offset markets before rushing into them and signing an agreement.