Published on March 29th, 2010 | by Tina Casey13
Cargill Generates Sustainable Biogas from Cow Pies
It looks like our energy future is at least partly in the hands of cows, now that agribusiness giant Cargill has joined the manure-to-biogas gold rush. The company has just announced that its second biogas project is up and running at the Bettencourt Dairy B6 Farm in Jerome, Idaho. Using manure produced by the farm’s 6,000 cows, the biogas project is generating enough renewable methane to make electricity for about 1,100 typical homes. That’s just the latest installation in a trend that is seeing manure-to-biogas facilities popping up on farms across the United States like mushrooms after a rain.
This is Cargill’s third foray into dairy cow biogas in Idaho. The venture also boosts the company’s involvement in the global renewable energy market, because it will generate about 28,000 tons of carbon emissions offsets. It underscores how rapidly the renewable energy sector is growing from small scale experimental roots into a fully commercialized global market force that is chewing away at the dominance of fossil fuels.
Cow Pies and Biogas
The basic process for producing biogas from animal waste is called anaerobic digestion. It has been around for at least thirty years and is fairly common in municipal wastewater treatment plants (yes we count as animals). The process involves enclosing manure in hermetically sealed chambers called digesters, where bacteria break down organic matter. It’s the same thing that happens in nature only it happens in a tightly controlled environment, resulting in a far more quick and efficient process. The end result is methane gas, which can be burned in generators to create electricity. New York State is aggressively promoting biogas technology as a money saver for small dairy farms; it provides renewable electricity to run equipment at the farm, it can produce high-value fertilizer for use on site or for sale off site, and it virtually eliminates the need to pay for off site manure disposal.
Biogas, Greenhouse Gasses and Water Quality
On a national level, the U.S. EPA has been urging the agricultural sector to adopt more biogas technology in order to reduce greenhouse gas emissions and prevent environmental damage from excess manure. Biogas facilities are becoming particularly important in watershed areas where stepped-up manure control is needed to preserve water quality. Biogas facilities could also help reduce demand for fossil fuels – which in turn could help prevent environmental damage caused by fossil fuel extraction methods such as hydraulic fracturing and mountaintop coal mining. If the carrot doesn’t work, there’s always the stick: hog producer Premium Standard Farms is facing a jury-awarded $11 million fine for environmental and public health problems relating to a factory farm operation, where massive amounts of manure that could have been recycled as biogas and fertilizer was instead dumped on open ground, untreated.
Piggybacking the New Green Economy
Cargill’s move into the carbon emissions market through dairy farms parallels a similar venture by Desert Hills Dairy of Nevada, which was the first dairy farm in that state to build a manure-to-biogas system. Like Cargill, Desert Hills is also leveraging the farm’s reduced greenhouse gas emissions to enter the cap-and-trade carbon markets. Nevada Hills also anticipates that the new biogas digester will enable it to expand operations without running afoul of environmental regulations. It’s a pretty compelling demonstration of how an industry that’s been around for oh say a few thousand years can piggyback onto – and thrive under - new transformational energy trends that are propelling us into the future.
Image: Calf by iLoveButter on flickr.com.
Update: For more information about manure-to-biogas systems check out the U.S. EPA’s sustainable agriculture program, AgSTAR.