In response to the lack of federal government action to mitigate climate changes many state and regional jurisdictions have developed and are developing climate policies that include carbon markets with specific provisions for agricultural Carbon Offsets and LCFS programs. In addition, many large multinational firms have defined climate policies and carbon neutrality goals. These goals will be achieved in part through carbon offsets but also through the procurement of RNG. Dairy biogas is an RNG feedstock that often contains substantially more GHG reductions compared to other biogas sources like food waste and landfill biogas. This provides dairy biogas with a substantial competitive advantage in the context of climate policies.
Cows exhale the majority of the methane that they produce. Manure methane is primarily produced by dairy cows but beef cows also produce lots of enteric methane. For 10-15 years researchers have been developing methods to reduce enteric methane emissions. Some of the methods include feed additives (e.g. synthetic chemicals or natural products like seaweed or flax seed), improved grazing management practices, or even modifications to the cows gut microbiome (think probiotics for cows). Over the next 3-5 years it’s expected that additional methods and offset protocols will be established to grow this segment of the carbon market in North America.
In order to meet expected demand for Carbon Offsets through 2030 in it’s Cap and Trade Program CARB convened the Compliance Offset Protocol Task Force to advise on new protocols that should be implemented. A protocol to reduce enteric methane emissions is one option under consideration since California is the largest dairy producing state with more than 1.6 million milk cows and more than 20% of total US dairy production.
In 2007 the Renewable Fuel Standard 2 law was passed by Congress which allowed for electricity generated from renewable feedstocks to qualify for RIN credits. In 2010 EPA initiated creation of a renewable electricity pathway within the RFS to generate eRINS, including from projects that use biogas to power electric vehicles. The eRIN pathway would offer another revenue stream for projects that are generating biogas. The EPA has yet to approve the eRIN pathway as part of the RFS, but Ag Methane Advisors as a member of the American Biogas Council is working to advocate for the approval of the eRIN pathway and the many benefits of eRIN credits to digester operators that produce electricity.
Alternative Manure Management
Alternative Manure Management Projects (AMMP) are developed to reduce methane emissions from manure storage. These projects lower methane emissions by avoiding methane generation rather than destroying the methane that is emitted. These projects include a wide variety of strategies, but generally consist of methods of reducing the amount of manure stored in anaerobic lagoons or the amount of time that manure is stored in anaerobic lagoons, in order to limit overall methane emissions. These alternative management strategies can benefit from carbon offsets as a revenue stream.
Soil Carbon Sequestration
Similar to how trees store carbon dioxide in their woody biomass (trunks, limbs, roots) and undisturbed soil (when leaves break down) pastures and grasslands and croplands that use “No-Till” and other conservation practices sequester carbon in the ground.
Several protocols exist to create carbon offsets from soil carbon sequestration. Some of these include the Grasslands Protocol and Soil Enrichment Protocol of the Climate Action Reserve.
In addition, recently (June 2020) the Growing Climate Solutions Act was introduced by a bipartisan group of US Senators. It proposes a carbon market related to agricultural carbon sequestration and already has support from many agricultural trade groups as well as private sector companies.