Manure-to-energy project touted as climate fix emits thousands of tons of methane

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A Wisconsin project dubbed the “world’s largest manure biogas project” emits nearly 5,000 metric tons of climate-warming methane annually, roughly equivalent to emissions from 30,000 gasoline-powered vehicles, according to state data that adds to concerns about the impacts of large-scale manure digesters. 

The biogas project in question, owned by BC Organics, LLC, emitted 4,921 metric tons of methane in 2024, at least in part due to a leak at the facility, according to its 2025 filing with the Wisconsin Air Management program. The facility also reported more than 26,000 metric tons of CO2 emissions in 2024. 

BC Organics takes in roughly 900,000 gallons of manure from 11 farms daily, and runs the waste through 16 anaerobic digesters to capture methane and produce renewable natural gas.

Such digesters are increasingly common in the US to deal with the massive amounts of waste generated at large-scale livestock and dairy farms. There are an estimated 394 manure-based digesters operating in the US, with more than 70 under construction, representing a 55% increase over the past decade. 

The selling point of such projects is their ability to reduce climate-warming emissions — especially methane — from animal waste.  Manure digesters reduced greenhouse gases by more than 13 million metric tons in 2023, according to the most recent data available from the Environmental Protection Agency (EPA). 

However, critics and researchers say a large amount of methane is still emitted into the air from these facilities, as seen in the case of BC Organics. And government incentives for more digesters are only encouraging more concentration of livestock and more waste.  

Digesters are “not the climate solution that they’re touted to be,” said Brent Kim, an assistant scientist at the Johns Hopkins Bloomberg School of Public Health who researches the benefits and potential harms of digesters.

Digesters are “not the climate solution that they’re touted to be.” – Brent Kim, Johns Hopkins Bloomberg School of Public Health

He and colleagues published a study last year that found manure digesters “only address a fraction of livestock-related greenhouse gas emissions” and that their hazards may outweigh their benefits. He said while research shows some benefits from digesters, including reducing odors and pathogen loads in manure, “the potential for new pollutants to be introduced into the air” remains. 

“There’s flaring … the gas is often burned or flared on site,” he said. “That can introduce not only methane but nitrogen oxides, sulfur oxide, particulate matter and other potential respiratory hazards.”   

A potent pollutant

Methane, which is a much more potent greenhouse gas than carbon dioxide, is often converted to a “carbon dioxide equivalent” to measure its climate impact. BC Organics’ 2024 methane emissions are the equivalent of 140,000 metric tons of CO2, or the emissions of more than 30,000 gasoline vehicles each year. 

The annual total emissions of methane from all facilities in the US — including power plants, landfills, refineries and other sources — is the equivalent of 60.4 million metric tons of CO2, according to the EPA Greenhouse Gas Inventory, which does not include agricultural sources. 

In Wisconsin, the annual methane emissions are the equivalent of 1.5 million metric tons of CO2, according to the EPA inventory. BC Organics’ methane emissions alone total nearly 10% of the emissions from all of the state’s non-agricultural sectors. Its methane emissions dwarf those from other, smaller manure digesters in the state. The next highest methane emission total from a manure digester project was just 307 pounds, according to state filings.

BC Organics is likely reducing the overall methane emissions from participating farms given that it uses captured methane to produce renewable natural gas. It’s unclear how much those savings are, but the project’s website says it produces 1,630 MMBtus (Million British Thermal Units) of renewable natural gas — which is generally more than 90% methane — per day. 

Company officials did not return a request for comment on methane reductions, emissions or leaks. In its 2024 filing with state regulators, BC Organics responded “yes” when asked if there were “deviations or leaks” that resulted in emissions. The company also wrote that they “did have some venting off the digesters.” 

Craig Czarnecki, the air management outreach coordinator at the Wisconsin Department of Natural Resources, said the department discovered a leak in June 2024 during an inspection.

“The department is working with BC Organics to address potential leaks and odor complaints,” Czarnecki said. “BC Organics has been installing equipment upgrades to prevent future leaks.  The new components are to be fully installed by the end of May 2026.”

“The department is working with BC Organics to address potential leaks and odor complaints.” – Craig Czarnecki, Wisconsin DNR

He added that BC Organics has a confidentiality agreement with the department so specifics of the upgrades cannot be disclosed, and that inspections for “major” sources like BC Organics occur on a two-year cycle. 

Loan delinquency  

BC Organics was part of a push by the Biden administration to invest in biogas projects, including manure digesters, however, a January directive by the US Department of Agriculture (USDA) announced a three-month pause on loans aimed at promoting anaerobic digesters due, in part, to loan delinquency. The agency cited $102.6 million in delinquent loans for anaerobic digesters but did not name the companies in delinquency.

An analysis by The New Lede of the USDA’s Lender Lens portal showed four anaerobic digester loans in delinquency that total $102.6 million — with $100.1 million of the delinquent loans belonging to BC Organics, which is between 181 and 360 days delinquent on the loans that were originally for more than $104 million combined. The only other USDA loans for anaerobic digester projects in delinquency are $891,179 for Dovetail Energy LLC in Ohio, and $696,492 for Ringler Energy LLC in Ohio, according to the portal.

BC Organics is currently seeking a permit renewal in the Town of Wrightstown, where it is located. Town officials discussed the renewal in a March meeting, but went into closed session for the discussion despite the rest of the meeting being open to the public. 

Wrightstown officials said they are not commenting on the permit renewal at this time. 

Featured image: Austin Santaniello/Unsplash +