January 6, 2016, Sacramento, CA – Dairy methane digesters are among the most cost-effective investments the state can make to reduce greenhouse gas emissions and help achieve California's climate change prevention goals, according to a new study by Ramboll Environ.
The study examines how cap and trade auction proceeds are being invested by the California Air Resources Board.
"Dairy anaerobic digesters are a proven and highly effective method of reducing greenhouse gases, particularly methane, from agriculture," said Dr. Dawn Chianese, the study's primary author. "As such, dairy digesters are a smart investment of auction proceeds, particularly in light of their ability to substantially reduce short-lived climate pollutants and their potential to provide significant criteria pollutant reductions and benefits to disadvantaged communities."
According to the study, projects currently funded by the state provide a return on investment ranging from as low as $2 to as much as $1,250 per metric ton of carbon dioxide equivalents reduced. Dairy digesters represent one of the most cost effective investments of state funds with a rate-of-return of just $7 per ton of reduction. Equally important, because dairy digesters destroy methane, a short-lived climate pollutant, the value to the state's efforts to address climate change is much greater because climate-forcing emissions reductions can be realized sooner. When these short-term investments are factored in, the cost per ton of reduction is closer to $2, and as a result, even more cost effective.
"Dairy digesters provide great bang-for-the-buck when compared to other investments," said Michael Boccadoro, executive director of Dairy Cares. "California and Governor Brown need to make a five-year commitment of at least $100 million per year to help the state address dairy methane emissions and make major progress toward the state's ambitious climate protection efforts."
Speaking at the United Nations Climate Summit in Paris in December, Governor Brown said that tackling short-lived climate pollutants (SLCPs) "is probably the most immediate challenge, and the most important thing to do leaving this conference." This declaration follows his announcement last September that California was launching an aggressive effort to reduce methane emissions and other SLCPs.
The Governor's emphasis on the importance of reducing SLCPs is backed by the University of California's Climate Solutions Group. The group identified SLCP curtailment as the number one "science solution" for reducing greenhouse gases, and highlighted the value of bio-methane as a clean energy source.
Methane, which over 20 years has about 72 times more heat-trapping ability than carbon dioxide, comes from a variety of sources and is responsible for about 20 percent of California's greenhouse gas emissions.
The report can be read here.