Got Poop? Dairy Farmer Taps Cows for Renewable Energy
An innovative California dairy is getting a bit of press for tapping one of its most abundant products to make electricity. On Friday, Antonio Brasil's dairy in the Merced County town of Dos Palos unveiled its newest feature: a 240-kilowatt power plant fueled by cow poop.
The unveiling of the 10,000 square foot digester was hosted by Fresno area Congressional Representative Jim Costa, who lauded the joint venture between Brasil and Carson City, NV-based Elite Energy.
"What we're really talking about here is protecting water resources, protecting the air quality and climate, creating a renewable energy stream," said Costa.
The project's anaerobic digester will create a stream of something besides renewable energy, as well: about 18,000 gallons of liquid compost a day, and 25 cubic yards oof soil amendment.
A typical dairy cow produces about 180 pounds of manure and urine every day. California, which produces a bit more than a fifth of the nation's milk supply, has about 1.8 million cows. That's a huge waste stream, and it's an environmental problem. Nitrates from dairy farm effluent can seriously pollute air and water, not to mention making life miserable for neighbors in a more strictly aesthetic sense.
And that problem has gotten a lot worse in recent years, as Central Valley dairies expand production to serve an emerging cheese market in China. As much as 200,000 tons of waste nitrogen goes from California dairies to the state's groundwater each year, and an unknown amount of pollution volatilizes and makes smog-forming chemicals in the air.
"Definitely, there's a carrying capacity for dairy, and it's air quality," Brent Newell, legal director for the Center on Race, Poverty & the Environment told KQED in June. "You can't keep sticking more dairies in the San Joaquin Valley in order to export cheese to China."
The digester on the Brasil dairy may offer a small step toward turning that problem into a solution to other problems, like getting the state off fossil-fuel derived power. The facility can accept waste from about half of Brasil's 3,000 cows. Manure and urine move in stages through six 20,000-gallon tanks, which heat the waste stream to 135°F and generate methane. The methane is siphoned off to run a power plant connected to the grid. The high temperatures pasteurize the remaining waste, theoretically rendering it safe for use as organic fertilizer for farming and horticulture. Much of the resulting compost will be used to fertilize fodder crops that feed dairy cows: an elegant closed circle.
According to the Merced Sun-Star, the system may allow dairy owner Antonio Brasil to expand by reducing his operation's nitrate load on the Central Valley's air and water. But Brasil told the Sun-Star that his main interest in the project wasn't about his business's bottom line. "It helps the environment," he said.