The Obama Administration is targeting emissions of greenhouse gases (GHGs), particularly methane, from the agricultural industry as a component of its recently announced Climate Action Plan – a Strategy to Reduce Methane Emissions. According to EPA’s inventory of GHG emissions, the sources of U.S. anthropogenic emissions of methane include 25% from enteric fermentation (i.e., natural digestive processes in livestock, primarily cattle, that are “eructated” by the animal) and 9% from manure management (primarily as a result of anaerobic digestion in manure lagoons, pond, tanks or pits at feedlots and dairy operations).
The U.S. Environmental Protection Agency, U.S. Department of Agriculture, and U.S. Department of Energy are expected to release a “Biogas Roadmap” in June of this year to provide assistance to the dairy and livestock industries in voluntarily reducing methane emissions from manure management through the use of methane digesters and similar technologies. The Administration has targeted a 25% reduction in U.S. dairy emissions of GHGs by 2020.
These agencies have been collaborating in the development and promotion of anaerobic digestion for over 20 years through the voluntary AgSTAR program. The AgSTAR program conducts farm digester training and information exchange, helps develop tools for developing and adopting digester technology, recognizes farmers for voluntary initiatives and collaborates with various federal and state environmental, agricultural and energy programs.
The Administration’s overall Climate Action Plan outlines a number of policies and executive actions to reduce GHG emissions across the country and across all industry sectors. The Biogas Roadmap will likely take some of the voluntary aspects of the AgSTAR program and impose obligations and deadlines on the agriculture industry to meet the Administration’s climate goals. Although anaerobic digestion is an existing technology that is widely used in wastewater and industrial waste treatment, the agriculture industry should be prepared to consider other manure management options in addition to anaerobic digestion. Such management options focus on managing manure as a solid or in ways other than in lagoons that encourage the generation of methane gas through anaerobic decomposition.