Capturing Cow's Burps and Farts for Renewable Natural Gas

In Stevens county we have some of the largest dairy operations in the state. In recent years, large dairy operations and other CAFO’s or Concentrated Animal Feeding Operations have received a lot of backlash from climate activists and environmentally concerned citizens. These CAFO’s are responsible for a large portion of greenhouse-gas emissions related to the production of animals for food. Of these emissions, methane comprises around 44% with carbon dioxide and nitrous oxide making up the remaining 56%. Methane, is a greenhouse-gas that is twenty time more potent than carbon dioxide. Nitrous Oxide is also more potent that carbon dioxide, 298 times more potent. This means that one pound of nitrous oxide contains the same warming potential as 298 pounds of carbon dioxide. And that one pound of methane contains the same warming potential as 20 pounds of carbon dioxide. Thus, curtailing not just CO2, but also reducing methane (CH4) and nitrous oxide (N2O) is of the utmost importance in order to limit warming.

One company is seeking to limit the methane that is released as a result of these CAFO’s. The company, AmpAmericas, is creating facilities that can collect waste from farms and other industrial operations and convert it to a carbon negative fuel. Although the fuel still contains carbon and releases carbon dioxide when it is burned, since it is captured from a waste stream that would otherwise be wasted, it is considered carbon negative. The mission of AmpAmerica’s is to “Build, own, operate, and profit from a portfolio of assets producing 100% renewable, carbon negative fuels and feedstock’s from waste at farms, industrial facilities, and municipal waste facilities.” Their first plant was established in Indiana in 2012 collecting 1.5 million gallons of manure every day from 36,000 cows across nine dairy operations. They acquired full operational control of the plant in 2019. Soon after they acquired additional renewable natural gas assets in Idaho. The dairy’s in Idaho send nearly 1 million gallons of waste per day from 36,000 cows to two methane digesters and one electrical plant. The plant in Idaho will reduce emissions by over 170,000 metric tons each year. This is equivalent to taking over 36,000 cars off of the road.

In 2020, AmpAmericas began operating a new RNG facility in Stevens County starting in 2020. The plant processes biogas collected from manure ponds at Riverview, West River, and District 45. The plant processes 700,000 gallons of cow manure each day. It will reduce greenhouse gas emissions by around 100,000 tons each year which will be equivalent to taking 20,000 cars off of the road. This also the first dairy-waste-to-transportation-fuel plant in the state of Minnesota.

But I was wondering, how does cow manure, a traditional waste product of an industrial process, transform into a carbon negative, renewable, and clean transportation fuel? A couple of weeks ago I got the opportunity to visit the Amp America’s RNG productions facility. Down a long and bumpy dirt road, the unassuming building appears on the horizon as any other pole barn or other agricultural building would. Upon getting closer to the facility, a tall metal fence topped with barbed wire becomes visible. The building looks big enough to store a 4 or 5 of grain hopper trailers.

Once inside, a definite hum can be heard throughout the interior. Nick Grecula is the plant operator and greeted me when I came in. He explained that bio gas is siphoned off of the manure ponds and piped through a pipeline to their central treatment facility. The facility has three main processes; distilling the biogas by removing carbon dioxide and hydrogen sulfide, pressurizing the methane rich renewable natural gas, and injecting it into the Alliance pipeline. The end product is shipped primarily to the west coast where 9 % is used to produce energy, 17 % is used to fuel heavy duty trucks, and an additional 8 % is used for residential heating a cooling. The rest of the RNG is used in varying other industrial settings.

I wondered if there was any difference between how RNG performs against natural gas extracted from the ground. Nick insisted that aside from negligible differences in the concentrations of certain molecules, the RNG fuel performs the same as fossil fuel based natural gas.

The facility features some of the most advanced technology in the industry, primarily sourced from European producers. This is because, while there is a giant potential for biogas production in the United States, much of the development and leadership in the field for the last two decades has been from European producers. And as war continues to effect the supply of natural gas to the EU, biogas production is only becoming more important. Instead of having to rely on the mineral resources of a volatile nation-state, European leaders can instead rely upon biogas production from CAFO’s and from Municipal Solid Waste landfills where methane is already produced in great quantity. AmpAmerica’s is the largest small RNG company in the US and they hope to develop a network of biogas production hubs across the Midwest and northern plains. They are even looking into storing the RNG similar to how natural gas is found naturally in subterranean reservoirs. This would allow for a storage option that requires less energy that traditional natural gas storage technologies.

As Morris, and greater Stevens County, continues to solidify itself as a leader in the sustainability arena, it will be interesting to see how these green fuels could be incorporated into farm fuels. This would allow for a closed loop system where the methane produced from cows eating food harvested in Stevens county fields is used to power the implements that planted, grew, and harvested said food. Closing loops like this by linking waste streams to bio gas and green fuel needs will allow us too transition to greener technologies without changing the base infrastructure we already rely on.

This article was originally published in the Stevens County Times

My position with the City of Morris is funded through a grant from the ENRTF. To learn more, head to https://www.legacy.mn.gov/environment-natural-resources-trust-fund