Bryan Sievers’s roots run deep in Scott County, Iowa. It’s where his great-grandparents settled in the late 1800s; it’s home to the family’s century farm; and it’s where Sievers farms today. He grows corn, soybeans and hay and runs a 2,400-head cattle feedlot. In 2007, Sievers began looking at ways to expand the feedlot while reducing its carbon footprint.
Anaerobic digesters turn waste into energy
Inspired by the anaerobic digesters he saw on a trip in Germany in 2009, Sievers began looking into adding it to his farm, as it aligned with his vision to maximize the farm’s natural resources and reduce its carbon footprint.
Bryan Sievers inspecting his cover crop stand in May 2022.
What exactly is an anaerobic digester?
Sievers explains a cow is a great example of a natural digester. The animal can digest roughage, corn, wet distillers’ grain and more. One of the byproducts of that consumption is methane. Anaerobic digesters also digest organic materials to produce methane, but Sievers explains they take things a step further, harnessing the methane.
In an anaerobic digester, manure is combined in the digester with other organic materials like food waste, wet distillers’ grain or cover crops. The methane gas is collected and used to power engines that produce electricity and thermal energy. It can also be cleaned and used as fuel for transportation or for home gas appliances. The cleaning process “scrubs” the methane to remove any impurities, making it usable in the home, gas tank and beyond.
“The digester on our farm was finished in 2013. For the last 10 years, we’ve focused on running the farm in what we like to call a ‘closed-loop approach to agriculture production,’” says Sievers. “We put manure and the other organic materials into the digester, and we use the methane it produces to power our farm.”
A bird’s eye view of Sievers family farm in Scott County, including cattle barns and anaerobic digesters.
Efforts to broaden impact of innovation
Sievers believes other Iowa farms can benefit from anaerobic digestors and is involved in efforts to make that a reality. He serves as a vice chair on the board of directors for the American Biogas Council, which is looking to find new ways to utilize methane from anaerobic digesters, or biogas, within the supply chain.Click here to see more...