"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."
