Manure digesters are among the best-known ways for feedlots and dairy farms to capture greenhouse gas emissions and, in some cases, sell biomethane as a fuel. The climate, healthcare, and tax law signed this week by President Biden offers a new incentive to the biogas industry at the same time that the environmental credentials of on-farm digesters are being questioned.
Many livestock farms employ lower-emissions practices, such as grazing or dry-manure management, said a report from the Center for Agriculture and Food Systems (CAFS), based in South Royalton, Vermont. At the same time, the group said, “significant public funds” are channeled to biogas-eligible facilities. “This sets the perverse precedent of neglecting historically good actors while rewarding the worst polluters in the livestock industry with new revenue and positive public relations.”
Because digesters are expensive to install and require a steady supply of livestock waste to process, factory farms with at least 500 cows or 2,000 hogs are the leading beneficiaries of an array of state and federal incentives to use digesters to reduce emissions from livestock farms, said CAFS. “It is imperative that policymakers and others recognize that manure biogas systems reduce emissions from only part of this [livestock] system — manure management.”
Proponents say digesters are “win-win” devices that reduce both greenhouse gas emissions and the reliance on fossil fuels. The CAFS report said digesters should be evaluated on a broader scale that considers the impact of emissions, odors, and noise from large livestock operations as well as alternative methods for controlling gases, such as changes in livestock feed, that would reduce methane generation by food animals. “The primary alternative policy mechanism should be to treat industrial livestock operations like every other industry in the country and regulate the emissions.”
Under the climate, healthcare, and tax law signed by Biden on Tuesday, “qualified biogas properties” became eligible for an investment tax credit for renewable energy alongside solar and wind power.
“For the first time, the system of tax credits in the bill supports all biogas sectors: wastewater, farm, food waste, and projects that produce renewable electricity, renewable natural gas, and renewable heat,” said the American Biogas Council. The trade group said that the $1.96 billion earmarked in the legislation for the USDA’s Rural Energy for America Program “will help our industry work with agriculture to increase sustainability and productivity.”
There are 2,300 operational biogas systems in the country, amounting to 15 percent of the potential U.S. capacity, said the group. “Meanwhile, we produce 65 million tons of food waste; manure and waste from 8 billion cows, chickens, turkey, and pigs; and more than 11 trillion gallons of wastewater each year.”
Early this year, agricultural economist Aaron Smith calculated that dairy farmers in California with a manure digester could earn $2,800 in air pollution and biofuel credits a year from the manure produced by each of their cows.
The CAFS report, “Rethinking manure biogas: Policy considerations to promote equity and protect the climate and environment,” is available here.