Manure Power In The Spotlight
The New York Times has an excellent story on 'poo power,' a technology that we have covered extensively and which makes us think the Gray Lady is following our green lead. Excuse the self-flattery please, and we'll try to get the cows back in the barn. First off, we urge you to read the original Times story. There's no point in repeating their well-reported analysis. But there are some by-ways and meta-stories we'd like to explore with you.A critical idea that was downplayed actually it was only hinted at in this story is that methane has a stronger greenhouse or "climate forcing" effect than C02. The benefit of capturing methane before it escapes a farm manure pond, subverting its destiny of dispersing to the stratosphere, far exceeds the obvious short-term gains of making methane and its byproducts useful for farmers. Farmers, incidentally, need no prodding to move forward. From the NYT article: "Two years ago I couldn't even convince farmers that digesters work," said Melissa Dvorak, marketing manager for GHD, a company based in Chilton, Wis., that sells digesters. "Now, all they ask is what the payback will be."
Our meta-story is from the origin of the technology improvements that favor poo power. It's Denmark...again. The hint was found in a quote: "Environmental Power is phasing out an older business in burning waste coal to focus on its Microgy subsidiary, which uses a technology that it licensed from Xergi, a Danish company". Vestas, the Danish wind turbine manufacturer that brought economically viable modern turbines to the US had its industrial roots in the making of farm equipment. Makes us wonder what else those Danes have up their manure covered sleeves?
At first glance, the paradox posed by this technology is that the economics of installing manure digesters favor large-scale industrial farms. Will the emergence of manure-to electricity plants drive family-run organic farms out of business? Not necessarily. Organic farmers put their manure back into the soil. Soil management is the crux of sustainability for this technology. The cost of petroleum based fertilizer is the corollary driver.
Finally, we'd like to point to a historic irony, stemming from this quote in the article: ""We're not taking any risk, the reduction in odors is huge, and we're powering 600 homes with 900 cows," he said. "You've got to admit, that's pretty efficient."" The manure of three cows power a home. That's an interesting ratio.
When dairying came to the US from colonial era Europe, it was from a tradition of two or three cows living in the stable under the home. Body heat from animal metabolism and from breakdown of manure kept the home warm as well. In that time, the tending of the cows and processing of milk, butter, and cheese was seen as 'women's work', integrated as it was into the home. The first obstacle, then, to the evolution of modern mega-dairies was to convince men that they could get involved in management of larger dairy herds, kept in separate facilities. With the present ascendancy of women-managed farms and the seeming reinvention of cow as energy source, what goes around truly has come around.