Manure Biogas and Its Link to Heightened Emissions – GWC Mag

A group of 11 U.S. Representatives wrote a letter in February urging Treasury Department Secretary Janet Yellen to revise a proposed rule for tax credits to benefit manure biogas production. The representatives support manure biogas production to reduce greenhouse gas emissions.

Agriculture represents 11 percent of U.S. emissions. Animal agriculture is the largest source of methane emissions in the U.S. Some think that manure biogas reduces methane emissions from animal agriculture. Manure biogas is a central part of the Biden administration’s methane reduction plan for agriculture. The Inflation Reduction Act has given billions of dollars for programs and tax incentives to support biogas production.

Methane is a short-lived greenhouse gas, and rapidly reducing methane emissions will help limit global temperature increases to 2 degrees Celsius. More than 150 countries, including the U.S., signed the Global Methane Pledge to reduce methane emissions by 30 percent from 2020 levels by 2030.

A Friends of the Earth U.S. and Socially Responsible Agriculture Project report found that manure biogas reinforces unsustainable and unjust industrial agriculture systems for decades to come. Factory farms raise hundreds of millions of animals for food. Those animals produce incredible amounts of waste that generate methane emissions, a greenhouse gas with a warming potential of 80 times that of carbon. Anaerobic digesters capture the emissions and produce biogas that can generate electricity or be turned into fuel.

“Manure biogas is a greenwashing measure that directly undermines the Biden administration’s promises to achieve environmental justice, meet our climate targets, and create fair markets for producers,” said Chloë Waterman, senior program manager, Friends of the Earth U.S.

Manure Biogas Relies On Factory Farms

Manure gas production is impossible without concentrated animal feeding operations (CAFOs). A CAFO is a “specific type of large-scale industrial agricultural facility that raises animals, usually at high-density, for the consumption of meat, eggs, or milk,” according to the U.S. Centers for Disease Control (CDC). The manure production on CAFOs ranges from 2,800 tons to 1.6 million tons a year. A large CAFO can produce more manure than some U.S. cities. For example, a CAFO with 800,000 pigs could produce over 1.6 million tons of manure annually, one and a half times more than the waste produced by Philadephia in one year.

Human waste requires sewage treatment plants, but livestock waste has no treatment facilities. The vast quantities of manure a CAFO produces are much more than farms can use for fertilization. Many CAFOs do not grow their feed, so they do not need fertilizers. As a result, CAFOs come with a slew of public health and environmental problems. These problems include higher amounts of ammonia during anaerobic digestion, more nutrients in the leftover material that add to water pollution, and new pipelines and trucks that transport manure or biogas through communities. Biogas processing creates more air pollution than fossil fuel gas does.

Iowa has more CAFOs than any other state, almost 4,000, and ranks fifth in manure biogas production. Yet, in 2022, greenhouse gas emissions from agriculture increased. California has around 1,000 to 1,200 CAFOs. A state grant program to reduce emissions supports manure biogas production. According to a report by Inside Climate News, it results in around 225,000 to 300,000 tons of carbon every year, equivalent to emissions from 50,000 to 65,000 vehicles.

President Biden’s methane reduction plan for agriculture aims to reduce methane emissions by only nine percent by 2030. However, the report by Friends of the Earth U.S. and Socially Responsible Agriculture Project found that gradually reducing herd size will achieve over half of the needed methane reductions. CAFOs with digesters are more likely to increase their herd sizes. Herd sizes at CAFOs with digesters grew 3.7 percent year-over-year, 24 times the growth rate for overall dairy herd sizes in the states covered by the report.

A Better Way Than Biogas

A letter by 13 U.S. Representatives, Friends of the Earth U.S., and the Socially Responsible Agriculture Project opposed the U.S. Department of Agriculture’s decision to make practices used primarily by CAFOs eligible for the Inflation Reduction Act’s (IRA) conservation funding. “We oppose the inclusion of these practices, which further entrench the unsustainable, inhumane industrial model by funneling a significant portion of conservation dollars to a handful of large producers instead of supporting more small and mid-sized producers employing meaningful conservation practices,” the letter stated.

The report recommends that the federal government not create new funding streams or other policy incentives for manure biogas. It also recommends that the government pursue reducing methane emissions in ways that support environmental justice. Doing so would be a better way to reduce methane while not incentivizing CAFOs.