A modern dairy farm’s sustainability story: Making the most out of manure
This post is written by guest author Doug Block.
Hunter Haven Farm has evolved and grown over the years into a 950-cow dairy farm that also grows corn, alfalfa, wheat and soybeans in the rolling hills of northwestern Illinois. Our family is the fourth generation of dairy farmers, and we’re now working to equip the next generation to take over. All our milk is sold to Stockton Cheese about 30 miles from our farm where it is made into swiss cheese. I’d estimate that much of the Midwest has tasted the great swiss cheese that comes from our milk.
As a fourth-generation farmer, I can clearly see how much dairy farms have changed. Maybe that’s stating the obvious, given the milk you purchase is no longer delivered by the milk man from the dairy down the road (though, dairy is one product that is still very local – and you can find out where it came from).
But this change isn’t a bad thing. In fact, the evolution of dairy farms has been a good thing – both for the farm families behind your favorite dairy products and for the overall sustainability of those products.
In 2004, we made a big change: adding a methane digester to our farm that produces renewable energy – all with a natural byproduct we already have – manure. At the time, we were one of just 120 farms across the whole country implementing this technology. While our goal was to improve efficiencies on the farm, our methane digester has proven to have a sustainability impact beyond that.
How a methane digester improves dairy farm sustainability
So, what exactly is a methane digester? First, a little background.
On most dairy farms you’ll find concrete pits that store manure generated from cattle. What we’ve learned over time is that cow manure stored in these holding facilities produces methane, a greenhouse gas that can affect our climate. One way we can reduce the amount of methane being released into the atmosphere is with a methane digester, which generates biogas from dairy manure.
Here’s how it works:
- The digester holds manure in an air-tight tank and heats it to about 100 degrees.
- Bacteria in the manure thrive in these warm conditions, and they consume solids in the manure while releasing methane gas.
- That methane gas is captured at the top of the digester, converted to energy and used to heat the water on our farm, reducing our overall electricity use. Speaking of water, our water is used and reused about five times on our farm – from helping to cool milk down to washing our milking facilities to cleaning our barns to manure management.
- Through the biogas process, we also get a solid byproduct that’s dry and fluffy to the touch. We use this for bedding for our cows – just one more way we can “recycle and reuse” on our farm.
Check out this video that visually explains just how a methane digester like ours works.
Simply put, there’s not much that goes to waste on our farm. Everything has a purpose and a sustainability role to play. All of these investments and transitions have improved how we farm, reducing dairy’s overall carbon footprint to less than 2%. And we’re not settling there. Our dairy community has a net-zero initiative to be carbon neutral or better by 2050.
The great thing is that science continues to evolve, so our dairy farm sustainability journey will evolve for the better, too.
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