During the August 18 Hoard’s Dairyman DairyLivestream, four panelists discussed how investing in a methane digester could benefit a dairy operation by generating renewable natural gas to sell, reducing fertilizer and bedding expenditures, caring for their surrounding natural resources, and mitigating methane emissions.
Of course, that digester also represents a significant investment for the farm, and a dairy not milking thousands of cows might conclude that the cost couldn’t pay off for their business. However, that’s not always the case. There is no “magic number” of animals that decides if a methane digester is a smart option for a dairy, the group agreed.
“It really depends on your market,” said Mark Stoermann. As chief operating officer at Newtrient, which helps farmers implement sustainability projects that are financially beneficial, Stoermann is familiar with many different types of environmental opportunities.
For example, he shared that in Vermont, a program exists to provide a very high price for manure from smaller farms. There, digesters might be operating profitably on manure from 250 cows.
A farm might choose to install a digester for a variety of reasons, from simply controlling odor to caring for nearby watersheds. Stoermann noted that for the specific purpose of renewable natural gas (RNG), the greater costs to connect to pipelines means that it is more feasible for larger farms. Still, each farm, project, and situation is different. Goodrich Family Farm in Salisbury, Vt., one of the winners of the 2021 U.S. Dairy Sustainability Awards, uses manure from their 900 cows to create RNG that powers Middlebury College just 7 miles away.
Manure management
Cow numbers certainly are a factor to consider in taking on a digester project, but current manure management practices must also be taken into account. Richard Cooper of DTE Power & Industrial, one company that has invested in building and operating digesters on dairies, explained that the actual economics of getting revenue from a digester “depends on how much methane the state of California believes you’re mitigating.” This refers to the California Low Carbon Fuel Standard (LCFS), under which the majority of RNG produced in the U.S. is currently regulated.
Cooper echoed Stoermann’s point that RNG projects coming simply from manure (meaning no food waste or other materials), are more beneficial for larger farms. DTE has worked with farms from 1,500 cows, he said. “We’ve seen those work if they have really good methane characteristics.
“On the other hand, we saw a farm that was just shy of 8,000 milking cows, and that didn’t work simply because they were separating all their solids and there was relatively little organic matter being put in their lagoons,” he continued.
At the end of the day, these are complicated carbon mitigation markets, Cooper emphasized. Getting value from them depends on understanding the specific characteristics of each farm.
To watch the recording of the August 18 DairyLivestream, go to the link above. The program recording is also available as an audio-only podcast on Spotify, Google Podcasts, Apple Podcasts, and downloadable from the Hoard’s Dairyman website.
An ongoing series of events
The next broadcast of DairyLivestream will be on Wednesday, September 15 at 11 a.m. CDT. Each episode is designed for panelists to answer over 30 minutes of audience questions. If you haven’t joined a DairyLivestream broadcast yet, register here for free. Registering once registers you for all future events.
