From Methane Problem to Climate Solution: How Dairy Farms Across America Are Turning Cow Emissions Into Clean Energy

## Illinois Farmers Lead the Charge A [new report from Phys.org](https://phys.org/news/2025-12-illinois-dairy-beef-farms-methane.html) highlights how Illinois dairy and beef farms are transforming from methane sources into climate solutions. With the state's 400,000 head of cattle producing between 51 million and 88 million pounds of methane annually (equivalent to emissions from up to 260,700 gasoline-powered cars), addressing this issue has become a priority for forward-thinking farmers. ### The Science Behind Cow Emissions Cattle produce methane through a digestive process called **enteric fermentation**. Unlike humans, cows have a specialized four-chambered stomach, with the largest chamber called the rumen acting as a fermentation vat. Here's how it works: 1. **Cows eat grass, hay, or grain** and swallow it into the rumen 2. **Bacteria break down the plant material** in an oxygen-free environment 3. **This fermentation produces methane** as a natural byproduct 4. **Cows belch the gas out**, spending over 8 hours daily regurgitating and re-chewing their food (a process called "rumination" or "chewing cud") A single beef cow releases between 154 and 264 pounds of methane per year, mostly through burping, not flatulence as commonly believed. This methane is 80 times more potent than carbon dioxide at trapping heat over a 20-year period. The good news? Methane only stays in the atmosphere for about 12 years before converting back to carbon dioxide and being absorbed by plants. This creates a natural cycle, but the problem is that other methane sources (fossil fuels, landfills) are now adding to the total, causing the "bathtub to overflow," as experts describe it. ### Illinois Farmers Finding Solutions Fourth-generation beef producer Doug Hanson from Danforth, Illinois, earned the Illinois Beef Association's 2025 Environmental Steward of the Year award for his rotational grazing practices. "As we move through [the pastures], you'll see that they are all different," Hanson explains, describing his 70-acre property where cattle graze on diverse pastures of fescue, orchard grass, and clover. This approach offers multiple benefits: - **Diverse diets** can reduce methane production in the rumen - **Rotational grazing** allows soil to regenerate, sequestering carbon - **Manure spread as fertilizer** returns nutrients to the ground rather than sitting in methane-producing lagoons Similarly, the Lenkaitis family dairy in St. Charles works closely with a nutritionist to optimize their Holstein herd's diet, reducing emissions while improving productivity. Modern dairy cows eat "way better" than their farmers, jokes Sarah Lenkaitis. Their diet is "a very delicate dance" of dry hay, protein mixes, haylage, and ground corn. ### Promising Feed Additives Researchers are also developing feed additives that reduce methane production directly in the cow's gut: - **Bovaer**: A U.S.-approved additive that suppresses the enzyme involved in methane production, significantly reducing emissions - **Red seaweed**: Studies show adding small amounts of red marine algae to feed can reduce methane emissions by 80-90% "It has a cost, but if it doesn't elicit a production benefit, how can you ask the producer to pay for something like that?" notes Josh McCann, associate professor of animal sciences at the University of Illinois. Finding economic incentives remains key to adoption. ## California: Proving Digesters Work A [groundbreaking study from UC Riverside](https://news.ucr.edu/articles/2025/06/11/california-dairy-tried-capture-its-methane-it-worked), published in *Global Change Biology Bioenergy*, has validated what many farmers suspected: dairy digesters can reduce atmospheric methane emissions by approximately 80%. The research focused on a family-run dairy farm in Tulare County, the nation's top milk-producing county, where a giant, balloon-like tarp now covers their manure lagoon. "When the system is built well and managed carefully, the emissions really drop," said Francesca Hopkins, the climate scientist who led the research. More than 130 dairy digesters are now operating across California dairies, with the state investing heavily in methane control technologies to meet its goal of cutting emissions 40% below 2013 levels by 2030. [**Vander Woude Dairy**](https://www.caclimateinvestments.ca.gov/2025-profiles/anaerobic-dairy-digester-converts-methane-to-renewable-natural-gas-in-merced-county) in Merced County operates a hub-and-spoke model that exceeded projections, reducing 24,000 metric tons of CO2 equivalent per year. Meanwhile, **Calgren Dairy Fuels** operates a 12-dairy cluster in Tulare County that pipes renewable natural gas directly into the SoCalGas pipeline. ## Vermont: Federal Support Drives Adoption Vermont dairy farms received a major boost in 2024 when [three operations secured $2.4 million in USDA REAP grants](https://agriculturaldigesters.com/news/2-4-million-allocated-for-digesters-at-three-vermont-dairy-farms/) to install anaerobic digesters: - **Machia Brothers Dairy** in Sheldon received $747,124 for a system that will generate 1.96 million kWh annually - **Machia & Sons Dairy**, also in Sheldon, operates 1,300 dairy cows and views the digester as a way to diversify revenue amid volatile milk prices - **Percy Farm** in Stowe received $750,284 for a digester that will process farm manure plus off-site organic food waste Dustin Machia, who operates the family dairy farms, sees the technology as essential for farm viability: "This is about adapting to the future while maintaining our land for the next generation." Vermont's 14 existing digesters already reduce 74,000 metric tons of CO2 per year, with each average-sized digester generating enough power for 140 homes. ## The Business Case Gets Stronger According to the [American Biogas Council](https://americanbiogascouncil.org/american-biogas-council-marks-national-dairy-month-with-new-data-highlighting-increased-methane-capture-at-dairies/), the economics of dairy digesters have improved dramatically: - **471 dairy biogas systems** now operate across the U.S., processing manure from 2.3 million dairy cows - **$3 billion invested** since 2020, with $1.4 billion in 2024 alone - **60% now produce renewable natural gas** (RNG), commanding premium prices through carbon credit programs - **Federal and state grants** cover up to 50-60% of installation costs - **Typical ROI**: 5-7 years when combining electricity sales, carbon credits, and digestate fertilizer savings "They're not for every farm," Hopkins acknowledges. "But for dairies that can make it work, this is one of the most cost-effective ways we have to cut these greenhouse gas emissions." ## Wisconsin: Untapped Potential While Wisconsin currently operates 54 dairy digesters, the state holds the nation's highest potential for new installations, an estimated 561 additional viable sites. The Dane County Digester in Vienna became the state's first centralized multi-farm digester, serving three farms. **Holsum Dairies**, an 8,000-cow operation, has pioneered food waste co-digestion, earning over $400,000 annually in tipping fees from accepting organic waste from local businesses. ## What This Means for the Industry The U.S. dairy industry has already made significant strides: farmers now produce 60% more beef with 40% fewer carbon emissions than 50 years ago, and each gallon of milk creates 63% fewer carbon emissions than in 1944. The national herd has shrunk from 130 million cattle in the 1970s to 94 million today, yet we produce almost as much beef as ever. But as John Tauzel from the Environmental Defense Fund explains, the problem isn't that agricultural methane alone is overwhelming. It's that multiple sources are now "overflowing the bathtub" together. "We can't reach our goals of reducing methane if we don't also include agriculture in the solution set," Tauzel says. The good news? A global pledge to reduce methane emissions from livestock by just 30% over the next five years could limit global warming to 2.7 degrees Fahrenheit, and even reduce warming by over 0.36 degrees by 2050. --- ## Sources - [Illinois dairy and beef farms make raising cows part of the climate solution](https://phys.org/news/2025-12-illinois-dairy-beef-farms-methane.html) - Phys.org - [A California dairy tried to capture its methane. It worked.](https://news.ucr.edu/articles/2025/06/11/california-dairy-tried-capture-its-methane-it-worked) - UC Riverside News - [Anaerobic Dairy Digester Converts Methane to Renewable Natural Gas in Merced County](https://www.caclimateinvestments.ca.gov/2025-profiles/anaerobic-dairy-digester-converts-methane-to-renewable-natural-gas-in-merced-county) - California Climate Investments - [$2.4 Million Allocated for Digesters at Three Vermont Dairy Farms](https://agriculturaldigesters.com/news/2-4-million-allocated-for-digesters-at-three-vermont-dairy-farms/) - Agricultural Digesters LLC - [Dairy-Based Biogas Systems Surging](https://americanbiogascouncil.org/american-biogas-council-marks-national-dairy-month-with-new-data-highlighting-increased-methane-capture-at-dairies/) - American Biogas Council - [Anaerobic digestion on dairy farms](https://www.epa.gov/agstar/anaerobic-digestion-dairy-farms) - EPA AgSTAR Program