What Can Farmers Do About Climate Change? Methane Digesters

Agricultural carbon offsets have been a hot topic in both the environmental and agricultural worlds in the last decade in the fight to mitigate climate change. While there have been substantial hurdles to implementation, such as prohibitive monitoring requirements, there have also been significant gains over the last decade with the development of quantification methodologies in the voluntary carbon offset market and the adoption of ag-based protocols by the California Air Resources Board’s (ARB) in the state’s compliance offset market.

 

The American Carbon Registry (ACR) has been actively working with farmers and project developers on one project type that has been very successful in this space: the implementation of anaerobic digesters that allow dairy operations to decrease emissions through the destruction of methane gas via enhanced manure management. To date, just over 3.4 million metric tons of carbon offsets from livestock projects have been issued by ARB to be sold in California’s Cap and Trade program. What’s the big deal about 3.4 million metric fewer tons of emissions? It’s roughly equivalent to taking 718,000 cars off the road or unplugging the electricity just over 502,000 average American homes. That’s no small feat, and it’s important that dairy farmers continue to do the good work of combating climate change through improved manure management.

 

Livestock projects earn credits through the installation of a “biogas control system,” more commonly known as a digester, which captures and destroys the methane (biogas) through anaerobic treatment of livestock manure. The current protocol is also designed to allow for the same types of systems to be installed on swine farms. To date, all projects have been implemented at dairy farms, leaving room for opportunity at swine farms to reduce emissions and turn the environmental benefit into a secondary financial stream.

 

Often, dairy farmers will partner with offset project operators to help their dairies translate the work they’re doing on the ground into meeting the requirements of the Livestock Project Protocol. The ARB-approved protocol sets out the rules for eligibility, outlines how to determine emissions before the digester was installed, includes equations that should be used to calculate the emission reductions, and establishes the monitoring requirements to be met.