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AgSTAR Accomplishments

Infographic: Celebrating 20 Years of Anaerobic DigestioSince its inception in 1994, AgSTAR has made meaningful progress reducing greenhouse gas (GHG) emissions in the agriculture sector. Through outreach, education, training and other tools, AgSTAR continues to support anaerobic digestion of livestock waste.

Anaerobic digestion of livestock waste reduces GHG emissions in two ways:

  • Methane emissions are directly reduced as biogas is captured and used as a renewable fuel.
  • The energy generated displaces the use of fossil fuels, further avoiding the emission of GHGs and other pollutants.

Recent AgSTAR Accomplishments

“AgSTAR is a tremendous resource to the Nebraska Methane Workgroup. The program serves as a valuable conduit of information to connect states facing similar issues, and this has been particularly helpful.”
Joe Francis
May 2015

  • Approximately 253 anaerobic digesters are operating at commercial livestock farms in the United States. To find out more about these projects, explore the Livestock Anaerobic Digester Database.
  • In 2017, AgSTAR helped reduce GHG emissions by 3.95 million metric tons of CO2 equivalent (MMTCO2e):
    • 3.11 MMTCO2e direct emission reductions
    • 0.84 MMTCO2e emissions avoided

2017 AgSTAR GHG Emission Reductions

3.95 million metric tons of carbon dioxide equivalent reductions are equivalent to the energy used by more than 426,000 homes in one year
Greenhouse Gas Equivalencies Calculator

EPA’s Greenhouse Gas Equivalencies Calculator provides other GHG equivalencies.

Greenhouse Gas Reductions Due to AgSTAR Programs

The chart below shows the amount of direct and indirect greenhouse gas emission reductions from anaerobic digesters on livestock farms from 2000 through 2017. The chart shows a steady increase through 2013 with an estimated total of 3.95 MMTCO2e in 2017.


Year Direct Reductions
Indirect Reductions
2017 3.107799 0.845526
2016 3.031144 0.840556
2015 2.937968 0.821901
2014 2.959310 0.828159
2013 2.872028 0.795915
2012 2.472224 0.672904
2011 2.021629 0.465696
2010 1.651440 0.369123
2009 1.481067 0.306218
2008 1.364630 0.265527
2007 0.960538 0.161310
2006 0.874529 0.134101
2005 0.624855 0.100459
2004 0.463140 0.074157
2003 0.324475 0.052771
2002 0.275149 0.042846
2001 0.227956 0.031863
2000 0.101779 0.014573

In addition to these environmental benefits, AgSTAR has: