Global warming can provoke different reactions among each person who hears the words. Some are skeptical of the concept; some regard it as a certainty.
Regardless of your personal thoughts on the subject, your customers are concerned about it. Increasingly, they think about a product’s carbon footprint when making purchasing decisions.
While the pork industry has been progressive in addressing environmental concerns, the future will continue to require best management practices to reduce your carbon footprint. This will include carefully designed feeding programs that match the pigs’ dietary needs and reduce or eliminate waste nutrients. It also will include investment in and adoption of technologies to reduce emissions.
Gases that trap heat in the atmosphere are referred to as greenhouse gases. In pork production, greenhouse gases primarily arise from manure decomposition, as well as normal animal respiration. The three gases of concern in pork production are carbon dioxide, methane and nitrous oxide.
Measuring Greenhouse Gas
All gases are reported as carbon dioxide equivalents. Nitrous oxide scores 310, meaning a given quantity would contribute 310 carbon dioxide equivalents compared to the same quantity of carbon dioxide. Methane scores a 21, meaning it’s 21 times more efficient at trapping heat in the atmosphere.
According to the U.S. Environmental Protection Agency, animal production accounts for 203 million tons of carbon dioxide equivalents, or 2.9 percent of greenhouse-gas emissions in the nation. The pork industry specifically contributes only one-third of 1 percent of total U.S. emissions.
Greg Thoma, University of Arkansas chemical engineer, estimated the average farm-to-fork carbon footprint of a 4-ounce boneless pork serving, which includes production, preparation and serving, at 2.2 pounds of carbon dioxide equivalents. For perspective, a gallon of gas burned by a standard vehicle emits approximately 20 pounds of carbon dioxide equivalents.
Thoma’s study showed that the nursery-to-finishing stage contributed 53 percent to pork’s total carbon footprint, with about 14 percent from the sow. The study also showed that other food-chain sectors such as processing, packaging and retail accounted for 34 percent of pork’s carbon footprint.
The Council for Agricultural Science and Technology published a paper featuring experts from six universities, who looked at pork, poultry, dairy and beef operations, along with each industry’s efforts to mitigate air emissions.
Swine manure-storage systems are of particular concern regarding greenhouse-gas production. CAST points to long-term manure storage as a major source of biogases such as methane and nitrous oxide.
The paper outlines manure land application as having “the potential to be the largest emitter of air pollutants from animal production.” From a regulatory standpoint, the paper warns that “there may be regulatory limits on what can be emitted from the production site for certain gases.” (You can download the full report by going to http://bit.ly/k3CapI.)
It’s important to note that every pound of pork produced in the United States today has a smaller carbon footprint than it had 20 years ago. Since 1990, meat production has increased nearly 50 percent, yet greenhouse gases from animal agriculture have held relatively constant due to improved feed utilization and manure-management strategies.
Still, adopting best management practices can help you further reduce the industry’s carbon footprint.
What Can You Do?
On the plus side, generally anything you do to increase production efficiency or minimize waste will reduce your operation’s carbon footprint. For example, fine-tune diets to match the pig’s nutritional needs without overfeeding nutrients that end up in the manure.
“In general, an efficient operation will have a smaller carbon footprint,” says Teng Lim, University of Missouri Extension. “A farm that uses the least energy and feed to raise the same amount of pork is more ‘green’ than others.” For information on optimizing energy in swine production, go to http://bit.ly/l17xfD.
The full menu of strategies will depend on your individual farm, manure-handling system, nutrient-management plan and other variables. (See sidebar.) Design nutrient-management plans that match land-applied manure to the nutrient needs of the crops to be grown. Also, injecting or incorporating manure ensures that you get the manure’s full fertilizer value and reduces GHG volatilization.
Practices such as frequent manure removal from deep-pit storage facilities tend to reduce GHG emissions as well. For facilities with open manure storage, lagoon covers offer a practical approach to reduce GHG emissions as well as improve odor control.
An effective but expensive option is an anaerobic digester. “Anaerobic digesters extract the methane, while reducing GHG and odor emissions from the deep pits. Whether or not adding an anaerobic digester is practical depends on the farm size, type, and more importantly, the buy-back electricity rate (offered by the utilities provider) that you can get, as rates differ from state to state,” Lim says.
Manure put into the digester breaks down into biogas and a digested solid. If a farm is big enough to collect enough methane, there’s the option of selling carbon credits to others to generate revenue. “Odor reduction and more stable nutrients in the manure used as fertilizer are other benefits,” Lim adds.
Capturing carbon dioxide by adding shelterbelts and other landscape around swine facilities can help reduce your carbon footprint as well as preserve soils and cut down odor drift. Known as carbon sequestration, trees and plants such as grasses and crops absorb carbon dioxide from the atmosphere. The practice can reduce overall emissions of carbon dioxide, methane and nitrous oxide. (For more on carbon sequestration practices, go to http://1.usa.gov/rCxwB.)
Cutting electrical consumption or improving machinery and vehicle performance and fuel efficiency will shrink your carbon footprint, as well.
Keep vehicles, implements and electrical systems such as feed delivery, environmental controllers, heaters and ventilation systems maintained to run efficiently. When replacing vehicles or electrical systems, select energy-efficient models to reduce fuel consumption and electricity.
"To us, sustainability is the ability to endure," says Randy Spronk, a farrow-to-finish pork producer from Edgerton, Minn., who chairs the National Pork Board's environmental committee. "We want to ensure that the resources required in pork production are used as efficiently as possible, with little or no waste."
By focusing on GHG-mitigation efforts, you will be better prepared for any regulatory and consumer scrutiny that lies ahead. By focusing on production efficiency, each improvement you make, including the small steps, will help shrink your operation's carbon footprint in the end.
Calculate Your Impact
A new carbon-footprint calculator is in the final stages of development, and it will help you identify areas to reduce your farm’s footprint. The National Pork Board created the calculator to use on your own terms on your computer.
“The Live Swine Carbon Footprint Calculator is a tool to help producers identify and quantify the greenhouse-gas emissions at their operations based on their production choices. It will highlight areas with potential for improving efficiency,” says Allan Stokes, NPB’s director of environmental programs. “The calculator can be used for sow, nursery and finishing operations to aid producers in making farm-specific evaluations and decisions.”
Information and recommendations that the calculator generates are private and only for the producer’s use. No information is shared with or accessed by NPB or others.