Scope of activities
The goal of the Cold/High Anaerobic Digestion Community of Practice is to develop anaerobic digestion systems that are deployable in Arctic, sub-Arctic, and high-altitude rural areas to address sanitation issues and potentially provide a source of renewable energy.
While anaerobic digestion has been used for hundreds of years to treat human and animal waste and generate methane as an energy source, research on the feasibility of implementing these systems in Arctic, sub-Arctic, and high elevation ecosystems is limited and largely anecdotal. This consortium formed therefore to collect and consolidate information on anaerobic digestion of waste for these communities. We are also working to determine the feasibility of the multi-benefit use of anaerobic digestion for energy generation, as the cost and logistics of diesel for home heating in remote communities is an economic burden for these communities and has been found to be a cause of elevated childhood asthma rates.
To bolster these efforts, this group is collaborating with the Global Methane Initiative () to initiate studies and anaerobic digestion pilots as part of 's international focus on reducing barriers to recovering methane as a clean energy source.
Poop is a resource. Let's use it!
Team leaders
Embrey Bronstad
Washington State University
Margaret McCauley
U.S. Environmental Protection Agency (Website)
Accomplishments
Anaerobic digestion operators typically aim to maintain a constant warm temperature to keep their microbe populations steady. This is infeasible in small communities in extreme cold locations. A bench scale study found that freezing then thawing synthetic human feces resulted in a lag period but ultimately similar or even greater amounts of methane than baseline, unfrozen assays. These results combined with solar radiation data indicate that Alaska subarctic locations receive enough solar thermal energy in summer months to support seasonally operated, psychrophilic anaerobic digesters.