The U.S. dairy industry is in the process of figuring out its carbon “Hoofprint”
Published on Fri, 03/27/2009 - 8:57am
Coops and producer groups are teaming up with others up and down the dairy marketing chain, in an effort to gauge the industry’s impact on the generation of greenhouse gases thought to contribute to global warming. Part of the program involves a comprehensive survey being sent to about 8,000 dairy farmers, which asks questions about practices like on-farm energy use, feeding practices, and pasture, manure and water management.
When the results are tabulated, the organizers hope they’ll present a picture of the industry’s so-called carbon footprint. In addition, Rick Naczi of Dairy Management, Inc, the National Dairy Board’s contract promotion group, says knowing what is being practiced on the nation’s dairy farms will help in identifying ways to further reduce emissions.
But Naczi says dairymen have already done a great deal to reduce their imprint; he cites a study at Cornell that shows dramatic improvement since 1944. The Innovation Center for US Dairy has set as a goal a 25% reduction by 2020 in carbon emissions from the entire farm-to-table dairy marketing chain, and Naczi says, “From the standpoint of consumer communications, we wanted to be prepared to be able to say what we’re doing next.”
Although the industry hopes to learn a great deal from the survey, Naczi says they’ve already got an idea of the carbon impact of dairy production; they won’t reveal their estimate, because the survey is intended to show its accuracy. However, he says, they believe the majority of the carbon footprint from a gallon of milk comes from the dairy farm, and in turn, the “vast majority” of that comes from the cow. “About 60% of the dairy farm carbon footprint would be attributable to methane production by the cow,” says Naczi. “The rest of the footprint would be emissions from manure.”
Another source is the machinery on the farm—tractors and balers; milking machines; electricity. Jim Linn, a University of Minnesota animal scientist who helped to prepare the survey, says eventually they hope to be able to plug all of the data from the survey into a computer program, and have it spit out a result. “That’s going to take a while,” he says. “In talking to people, when I start asking, ‘Well, how do we really measure the carbon footprint?’ we kind of draw a blank.”
Although information from the survey will help in defining and calculating emissions, Linn expects it to show the dairy industry is already doing a great deal to protect the environment. “As we
develop practices,” he says, “we talk about different technologies to reduce greenhouse gas emissions, reduce nutrient losses from farms, and better nutrient management plans and recycling nutrients on farms. So, I think the industry as a whole is doing a very good job in trying to be environmentally friendly; there are just things that maybe we haven’t discovered yet that we can do better.”
As a dairy nutritionist, Linn will be particularly interested in the data on feeding practices. “The more forage the animals eat,” he says, “generally we get more methane production, and so the level of concentrate feeding will be in there; use of some of the technologies to reduce methane production in the animal; and then, what kinds of feeds and fibrous feeds are being produced on the farm.”
They’re not just looking at what’s being used on the farm; what it costs is also a factor. Linn says, “In some cases, adoption of pro-environmental practices increases cost and can create hardship for producers…we have to recognize that those have to be borne by somebody as well; we can’t expect our livestock producer to bear all those costs, if it’s bettering the society as a whole.”
Naczi says industry leaders recognize society may eventually force greenhouse gas measures upon dairy farmers; that’s why they’re trying to get out in front of the issue and encourage voluntary adoption of carbon-reduction initiatives. “It’s just good business,” he says, “and it’s also good from the standpoint of our image with the consumers, that we’re out there actually pro-actively doing this kind of work.”
At the same time, he says, the coalition’s approach to sustainable dairy production emphasizes the economic, environmental and social benefits, with the economic value first; he says, “In a capitalist society, you have to make money at these initiatives, and all of these initiatives that we’re working on right now will return business value.” Most of the time, he adds, “sustainability and efficiency are almost synonymous.”
Emissions control on dairy farms, however, presents not just cost but also opportunity, and the option that’s attracted the most interest is methane digesters. The devices convert gases from methane into energy; Linn says so far, they’re working out well for the few Minnesota producers who have installed them. Some are selling the electricity or producing directly into a natural gas pipeline; “There’s even a few research projects now,” he says, “looking at how we capture that gas and can store it on the farm, and possibly be using it in some farm implements.” Although they’re currently cost-prohibitive for smaller farms, Linn sees the technology advancing so that a dairy with just a couple of hundred cows could use them.
But the concept hasn’t worked as well in California, according to Cynthia Cory, director of environmental affairs for the California Farm Bureau Federation. “It is a regulatory quagmire,” she says, “because in California we have so many regulations, from the Air Board, from the Water Board, from the Integrated Waste Board.”
The problem is with the process by which the methane is converted into renewable energy; Cory says it involves combustion and nitrogen oxides (Nox), a criteria pollutant that is regulated under the Clean Air Act. She says, “The standards for NOx are so low in the San Joaquin Valley now, they will not give you a permit for practically anything. And even though these are minor NOx emissions in the scheme of things, especially when you compare it to the methane that you’re reducing, it still is becoming a regulatory nightmare.” As a result, she says, “I’ve got very progressive dairy farmers who are not able to get a local air permit after they’ve built this expensive methane digester.”
There are supposedly “Nox lean burners” on the market that can help digesters meet the standards; Cory says they don’t work as well as advertised and are expensive to buy and maintain, but the Air District was persuaded to establish their use as a requirement. The solution, she says, “may be as a combination of trying to get them to relook at what technology is really out there—do we need to have it at nine parts per million? Could it be a higher NOx standard?”
This is a crucial issue to California dairy farmers because the Golden State has implemented its own global warming plan. The statewide target is to return to 1990 carbon dioxide emission levels by 2020; this would entail reducing emissions by 174 million metric tons (mmt), and agriculture’s share of that is pegged at 9 mmt. It’s not a mandatory program at this time, but Cory says the agricultural task force she worked with is seeking ways to meet the goal voluntarily; she says the digesters alone, if used by all of California’s first-in-the-nation dairy producers, would achieve 1 mmt of that.
“It’s not a ‘one size fits all’,” she says. “It’s going to really depend on the size of your dairy, and your infrastructure.” The methane doesn’t necessarily have to be turned into energy, Cory adds, although that’s the best-case scenario; the gas could simply be trapped and destroyed. “But we’re working on it,” she says, “because now with the greenhouse gas rules that are being put in place for California, there’s more of a push for renewable energy, so the electrical companies are looking for more renewable energy.”
Other potential sources of reduced emissions identified by Cory’s task force included carbon sequestration (“There’s just so much research that has to be done on California crops and conditions that hasn’t been done,” she says. “It’s just not ready for prime time”) and fertilizer applications. Cory says research is under way on whether dividing applications can reduce the amount of nitrogen lost through volatility “I don’t want to say that there’s a simple answer, and that we should rush and go say it can be done,” she says. “It’s a bit down the road before I think we’re going to—if ever—find anything that we can really point to and say, ‘This is a concrete way to reduce nitrous oxide, if you do this step’.”
Results from the dairy industry’s survey on producer practices should be released this summer; dairy processors have already completed their own study. In addition, Naczi says they’re compiling information on the retailers’ share of emissions, as well as dairy products transportation. The dairy checkoff is paying for the producer questionnaires, but those sectors are making separate contributions. “It’s a pretty representative group of people working on this to get it done,” he says.
They’re working together because they have a broad customer base to satisfy. “Our customers,” says Naczi, “the retailers and actual consumers, are getting more involved in their food production, and they’re asking about industries that are ‘being green’ and industries that are concerned about environment. That was really the driver that got us into this; it was actually a response to consumer interest.”