There’s nothing like the heady brew of barbecue, fried desserts and cattle that makes up a state fair. And where else can you see a 1,000-pound butter sculpture? At the Pennsylvania Farm Show last week, that crafted mountain of animal fat eclipsed even the excitement over the fair’s newly crowned dairy princess. But after the show closed, the prized half-ton of butter didn’t go to waste. It was sent to a nearby farm, where it was turned into electricity.
According to NPR, Brett Reinford, a dairy farmer from nearby Mifflintown, PA, was the lucky recipient of the sculpture. He promptly tossed it into his farm’s composting pit, where it mingled with rotting fruits, vegetables and manure. After being ground up, the mixture was thrown into the farm’s methane digester, where high temperatures and microbial activity caused the molecular breakdown that releases methane gas. That gas was then piped to the generator that powers the farm.
Based on the butter sculpture he digested last year, Rainford expects this one will net him about three days of power.
The downside to methane digestion is that industrial-sized machines aren’t cheap. They run about $1 million, but Reinford told NPR he expects to earn that money back within three years. Not only does his farm enjoy free electricity, he sells back the excess to his local utility company.
Reinford explained to NPR, "It runs our whole entire farm, and [creates] enough [power] for about 80 houses. So there's a lot of excess we sell back to the grid."
Methane digestion, also known as anaerobic digestion, is a trend that's gained a foothold in the dairy industry over recent years. In Vermont, Green Mountain Power is a utility company that supplies some of its electricity from the digested waste produced by 12 local farming partners. And Alliant Energy runs a similar program for its customers in Wisconsin, Iowa, and Minnesota.
These types of endeavors not only benefit the environment, but also the livelihoods of the farmers who take advantage of them. The New York Times reports that anaerobic digesters can produce another stream of revenue for dairy farmers, allowing them to stabilize their businesses even when milk prices drop.
Million-dollar digesters may be well and good for large-scale farmers, but what about the smaller ones, the type that don’t have access to six-figure sums? Smaller operations may be able to fashion their own digesting mechanism. According to The Urban Farming Guys website, there are a variety of ad-hoc methods that are scalable for smaller businesses, and even ones that work well for single-family households. Essentially, if you’ve got two trashcans and a tube, you’re in business.
Composting is still an effective way to recycle scraps and reduce the garbage sent to landfills. But the added benefit of anaerobic digestion for households is that it also produces natural gas that can be used for cooking and heating.
While methane digesters may still be cost prohibitive for many privately owned dairy farms, their growing emergence as a means of renewable energy is a big step in the right direction.
Would you ever try this at home? Let us know in the Comments.