Paul Wolcott, owner of the Lent Hill Dairy Farm in Steuben County, is used to turning one thing into another.
On his 4,000-cow farm in Cohocton, seeds become feedstock, which feeds cows, who then produce milk that the farm sells — two tractor trailer loads worth every day.
So it just made sense, he explained during a farm tour last month, to expand that cycle to accommodate another transformation: turning farm waste and food scraps into energy.
That transformation happens in a new facility on his farm called an anaerobic digester, which captures the methane generated as waste breaks down to eventually convert it into electricity.
“This is a part of that circle,” said Wolcott of the new facility, which looks like two giant green domes on the farm. “Making renewable energy out of the waste, and addressing climate change and greenhouse gas emissions.”
For many farmers and those in the renewables industry, anaerobic digesters present a multi-part business and environmental solution: divert farm and food waste from landfills, help farmers generate more income, and create a renewable energy source in the process.
But some environmentalists have a very different reaction. Amid a recent uptick in such facilities nationwide, some advocacy groups have staunchly opposed their development. Groups like Food and Water Watch say digesters can be damaging to the environment, incentivize farms to generate more methane, and risk leaking that methane into the environment.
As the fifth-largest dairy producing state in the country, New York is fertile ground for companies looking to construct more of these facilities. That’s sparked conflict between industry and environmentalists over whether the expansion of anaerobic digestion fits into the state’s future at all.
Digesting waste
Each day at the Lent Hill Dairy Farm, tens of thousands of tons of farm manure and food scraps from local businesses are fed into the digester, where bacteria break down the waste in a carefully-controlled process. While the farm waste comes from Lent Hill, the food waste is trucked in from nearby cheese and yogurt-making plants.
The facility acts “like a stomach,” said Rashi Akki, founder and CEO of Ag-Grid Energy, the company that partnered with the farm to build the digester. In goes farm and food waste —potential sources of energy — and out comes a kind of fuel, along with a leftover material that gets turned into fertilizer and animal bedding for the farm.
The fuel output is what the farm is most interested in. It's mostly made up of methane generated as the waste breaks down in the digester environment. When released into the atmosphere, methane gas contributes to climate change. But when captured, it can be used to power homes and businesses.
Ag-Grid Energy and the farm both get money from selling that energy to the local utility NYSEG, which then sells it to the yogurt company Chobani and Winsor Acres, a Broome County dairy farm.
“The main objective of the biogas is to convert it into electricity,” said Akki. Already, the facility is connected to the grid, where it’s estimated to produce 8 million kilowatt hours of electricity annually, enough to power over 700 homes.
Environmental concerns
State officials say installing digesters that process farm and food waste aligns with New York’s climate commitment of diverting waste from landfills, which are the third-largest source of human-related methane emissions nationwide.
The digester “fits perfectly in that need, that desire to divert from landfilling, and the emissions associated with that,” said Sally Rowland, the lead biosolids contact for the state Department of Environmental Conservation.
But Tyler Lobdell, an attorney with Food and Water Watch, said the organization opposes digesters on large farms precisely because of their climate impacts. He worries they incentivize farmers to produce more methane, which can leak and contribute to global warming.
“When manure breaks down naturally on a pasture, it emits an exceptionally insignificant amount of methane,” said Lobdell. “It’s once methane gets stockpiled and it finds itself in an anaerobic environment that lacks oxygen, that’s where methanogenic bacteria start to do their work and create methane from this organic waste.”
Essentially, Lobdell said it's better to deal with manure the old-fashioned way. Let it break down aerobically, with oxygen, and then use it as fertilizer. That process doesn’t create much methane, but it’s much less feasible for large dairy operations.
Environmentalists are also concerned about diverting food waste into the digester. That’s because scientists have found that food scraps can contain PFAS, the so-called “forever chemicals” used in food packaging that may be harmful to human health. If the food scraps fed into the digester have PFAS, then those chemicals can wind up in its material output that gets turned into fertilizer and animal bedding and risk contaminating soil.
“That’s really concerning from a scientific, public health perspective,” said Lobdell. Using the digested material back on fields “just ignores the reality of what has happened in that intervening digestion process,” he added.
Other research bears out these concerns too. A 2021 report from the Environmental Protection Agency found that food waste is a source of PFAS in material that comes out of digesters and recommends further study.
Looking ahead
New York has the third-highest number of digesters in the country, according to EPA data, making it far from the only state determining how anaerobic digestion fits into its energy future. California and Wisconsin both have large dairy industries where anaerobic digestion plays a key role.
But in New York, the economic incentives work a bit differently. That’s because the state’s climate act — the ambitious 2019 law that requires New York to obtain 70% of its electricity from renewable sources by 2030 — excludes biogas and biofuels from its definition of renewable energy. As a result, though electricity generated from wind and solar developments receive energy credits from the state, biogas facilities like digesters are generally only eligible for federal incentives.
That could stall the industry’s expansion in New York, according to Lauren Ray, an engineer at Cornell PRO-DAIRY, a research organization affiliated with Cornell University.
“Without something that allows for there to be a value on this energy format, I think that the growth may not continue,” said Ray.
Changes to the state's renewable energy incentives could be coming. Last year, the Public Service Commission began studying how other technologies, like those that generate biofuels, could help the state meet its climate commitments. Environmental groups have pushed back against incentivizing these “alternative fuels” in the past over concerns that they are not scalable and do not always result in emissions reductions.
Ag-Grid Energy’s Rashi Akki said she’s aware of many of the concerns over anaerobic digesters. Her answer is to continue to partner with family-owned farms and work to improve the technology.
“No system is perfect. I can’t say, ‘Yeah, we have no leak,’” said Akki, referring to concerns over methane leaks from the facility. “We need to continue to work on it, just like any other industry, we have work to do.”