Waste not : Anaerobic digestion a win-win for dairy farms, but it doesn't come cheap
SHEFFIELD — It's almost a rite of the growing season: the smell of manure wafting through your car windows as fertilizer is spread on farm crops.
But, at 280 farms across the nation, and almost 30 throughout New England, cow waste undergoes a process to become a nearly odorless liquid that doesn't make you roll up the windows. Not only that, the manure provides electricity and other benefits for the farm.
The process, called anaerobic digestion, is a boon for dairy farms, transforming what can be a nuisance into a multi-pronged tool that reduces greenhouse gas emissions. The costs of installing a digester, though, are daunting in an industry in which many businesses struggle even to make a profit.
Anaerobic digestion collects manure and food waste, depriving the mixture of oxygen to yield three byproducts:
- a liquid containing nutrients, used by the farm as fertilizer;
- biogas, which is converted into electricity for the farm and the power grid, and;
- a sawdustlike solid used for animal bedding.
Pine Island Farm in Sheffield — it's the largest dairy farm in Massachusetts, with 1,600 cattle of various ages — began exploring anaerobic digestion in 2007, and through loans and grants it started installing the necessary pieces of equipment until 2011, when the electricity started flowing.
The Aragi family, which owns the farm on Hewins Street, invested in the digester because it offers resources essential to the farm's success by transforming a commodity that already was in abundance.
"We're able to take this waste product and turn it into other, beneficial products," said Holly Aragi, the wife of co-owner Louis Aragi Jr. and who oversees the digester operations.
By repurposing the farm's cow waste, the digester poses less damage to the environment than traditional methods of managing manure. Instead of seeping into the atmosphere and contributing to global warming, the methane from Pine Island Farm's manure becomes electricity, which serves the farm and its neighbors through net metering.
Proponents of anaerobic digestion see the technology's environmental benefits as a key advancement in sustainable agriculture. The United Nations' Food and Agriculture arm estimates that over 14 percent of all human-caused greenhouse gas emissions comes from livestock, of which cattle are the biggest contributors. While most of those emissions stem from the belching of cows, up to 20 percent of a farm's cattle emissions can be reduced through anaerobic digestion, according to an estimate by Williams College environmental studies lecturer Sarah Gardner using UN data.
A serious investment
But, the environmental value of digesters is reflected in their cost.
For Pine Island Farm, installing a digester cost about $1.2 million. Even though the farm received a boost from grants and money designed to promote eco-friendly agriculture, the implementation was a hefty project.
"The farm has to take out-of-pocket expenses to do stuff like this," Holly Aragi told The Eagle during a tour of her farm. "Grants and everything are wonderful, but they come after they see you've got all your invoices and stuff together, then you get those payments."
"We managed to get by, but it was a real struggle because of that," she added.
The Aragis also faced difficulty securing a loan for the project, since digester technology was not as highly regarded when they started operations.
"This whole thing back then was a very risky type of thing," Holly Aragi said.
In the case of Pine Island Farm, the risks paid off, and the digester offsets expenses like bedding and electricity that the Aragis now produce themselves. Still, Holly Aragi doesn't like to write off the project as a "success."
"This is something that we decided to do, to take care of some issues that we had to deal with," she said. "This doesn't put me in a better position, by all means, than another dairy farmer. Because I think all farmers — we're in this together, and we just happened to find something that offset what we're trying to do to stay afloat."
Experts at Newtrient, an organization that helps farmers navigate decisions about manure management, agree that the choice to convert to a digestion system is not a universal one.
"It's definitely not the right solution for every single farm," said Jamie Vander Molen, the director of communications at Newtrient. "Each farm has their unique way of managing their manure."
When considering the viability of anaerobic digestion, the location of a farm matters, Vander Molen said.
"If they're generating electricity for the farm use, and then they have extra energy, is there a community nearby that they can feed it into the grid?" she asked.
The fuel created by a digester also can be used in natural gas, she added, so, proximity to a pipeline could signal anaerobic digestion's suitability for a farm.
While the size of a farm does not necessarily rule out the viability of anaerobic digestion, Vander Molen said the economics work better when a farm has at least 200 cows. The U.S. Environmental Protection Agency, meanwhile, recommends that farmers have at least 500 cows to install a digester. Those benchmarks are not infallible, though, as demonstrated by one farm in Vermont with a digester and only 45 cows.
Paying for it
The biggest piece of the economic puzzle, though, is finding sturdy sources of funding for the project. With the price of milk in a volatile state, it's daunting for dairy farms to launch large capital projects with no promise of immediate reward.
Many farms choose to pursue the venture with renewable energy companies, which work with farms to secure money for digester projects and provide brainpower to operate the complex systems. The companies usually incorporate the digester as its own corporation, giving a portion of revenue to farmers.
Mark Stoermann, chief operating officer at Newtrient, tries to inform farmers about the climate of renewable energy that they are entering. Some farmers, he said, would earn more capitalizing on their own manure, while others would be better off selling to a developer. When it makes sense for a farmer to sell, Stoermann advises them that some companies "have better deals than others."
"It truly is the Wild West out there when it comes to these contracts; there is no real standard," he said.
Darryl Williams, owner of Luther Belden Farm in Hatfield, had seen other Massachusetts dairy farms install digesters, and he agreed to try it when the renewable energy company AG-Grid approached him. While most of the revenue from the digester goes to AG-Grid, Luther Belden Farm is able to offset its costs and make the farm more financially secure.
"We're essentially trying to set the farm up for the next century," said Williams, whose farm has been in his family for 13 generations. "We saw this as an additional revenue source."
Eight projects in state
In Massachusetts, working with a renewable energy company is the norm. Of the eight anaerobic digester projects on dairy farms throughout the state, Pine Island is the only one not owned by a renewable energy company.
But, for Massachusetts farms building a digester, either independently or with a renewable energy company, a key source of funding has gone dry.
The Massachusetts Clean Energy Center's Organics-to-Energy program has been the main conduit for anaerobic digester funding in the state since 2011. The initiative has given almost $5 million in grants to design, build and renovate anaerobic digestion projects, plus more than $1 million in feasibility studies to evaluate potential ones.
But, the center sunsetted the program in its fiscal 2021 budget, which was approved by the center's board Tuesday. Organics-to-Energy received one application for an award in fiscal 2020. That application is pending.
While an anaerobic digester project still could be awarded money through $500,000 of unprogrammed money the Clean Energy Center has set aside, officials cast doubt on the likelihood of that happening. They say the decrease in funding reflects the shrinking market for new anaerobic digester projects in Massachusetts.
"We don't want to overbuild," said Amy Barad, program director for organics-to-energy, hydropower and wind at the Clean Energy Center. "We want the ones that have been built to be successful."
In addition to their wariness of competition among digesters, officials believe that there are not enough dairy farms left that could host an anaerobic digester to justify continuing the program.
"There aren't a lot more dairy farms that are large enough to contemplate this technology," Barad said, adding that finding food waste to co-digest with the manure also has become more difficult.
Thinking outside the box
Some sustainable agriculture advocates, though, argue that there is enough potential to continue the program.
Gardner, the environmental studies educator, said implementing anaerobic digestion is a key step to safeguarding the state's long tradition of dairy farming.
"It would be wonderful if every farm had an anaerobic digester," Gardner told The Eagle.
Anaerobic digestion decreases costs in an industry in which increasing revenue rarely is an option, she said. "It's something that every dairy farm would want to be a part of."
Still, Gardner recognized the difficulty of achieving that goal. Smaller farms would have to find innovative solutions to implement anaerobic digestion, such as partnerships with stores or restaurants trying to meet the state's food waste disposal ban, she said.
At Pine Island Farm, it's that innovative spirit that Holly Aragi credits for her farm's ability to keep going.
"We try to think outside of the box, do something different," she said, surveying a slurry pit awaiting digestion. "See where we can save what we can change, improve, that kind of thing."
Jack Lyons can be reached at firstname.lastname@example.org. Follow him on Twitter at @JackLyonsND.
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