Converting bovine waste into power is not new -- we've mentioned a Vermont project ("Providing renewable energy one cow at a time") and went into a bit more detail about a cattle ranch in California making electricity from manure. In both cases (and the undoubtedly countless others), the electricity is produced by letting the waste convert to methane, then burning the resulting gas in something called a "methane digester." Certainly a good use of cattle waste, but is it the best use?
The Haubenschild Farm in Minnesota, already generating methane digester-electricity, decided to check out other options. In January, they became the location of the first cow manure-powered hydrogen fuel cell.
Phil Goodrich, the University of Minnesota principal investigator in the hydrogen fuel cell project at the Haubenschild farm, last Friday backed the assertion that this was a world’s first. The project was to see if running methane gas produced from cow manure into a hydrogen fuel cell could make electricity.It was working, said Goodrich on Friday. He explained that electricity has been made from a fuel cell before but never from methane produced from “predigested, pre-collected, biomass.” [...]
The advantage of having a fuel cell produce the electricity from methane rather than a standard internal combustion engine-powered generator is the type of exhaust, Haubenschild said.The fuel cell’s water vapor exhaust is superior environmental-wise to the type coming out of standard engines, noted Haubenschild. That can help thwart the “not-in-my-back-yard” thinking that people have about electrical generators in their midst, and also get them to accept farmers helping supply energy for their neighborhoods, Haubenschild added.
It's a bit unclear just how much electricity the fuel cell is producing. The Princeton Union-Eagle, the hometown newspaper for the farm, claims 120Kw/h production, while the Minnesota Department of Agriculture describes the fuel cell as being a "5 kilowatt" device. Either way, it's not big enough to run the whole farm, but is certainly enough to power the residence or office.
It seems likely that the conversion of manure to electricity -- whether by methane digestion or conversion to hydrogen for fuel cells -- will increasingly become a standard part of ranching. And that's not the only way farms and ranches will contribute to the new world of distributed power. Wind turbines can co-exist with other land use quite nicely, and the Great Plains of the American midwest are prime wind-and-farm country. Then there's biodiesel and other biofuels -- not a total replacement for petroleum-based fuels, but a far more renewable (and carbon neutral) augmentation.
(Via Roland Piquepaille, who has some additional interesting links)
This technology is getting more and more attention. It's exciting to think Americans may have an alternative to Mid-Eastern oil, even in a small way.
The above url tells of a group of Engineers in Idaho that's near groundbreaking on the second digester. Rather than producing electricity, they plan to build a pipeline connecting several sites and sell the gas as fuel for heating, motor vehicle, ect.
As I mentioned, this is exciting to see come to pass....
Rick aka DBnDallas
I worked on this a bit in the mid 1970's, in Vermont. Looking at Vermont dairy farms, I saw some potential for methane, with the added benefit of improved manure for fertilizer after the digestion process. Problem was, to keep the digesters warm enough, one had to parasitize much of the methane. But all those farms have bulk coolers for milk - the coolers are heat pumps, and emitting that heat to air is inefficient. So a friend and I devised a water-based heat exchanger to the bulk tanks and used that to keep the methane digesters warm, boosting efficiency both of cooling milk and making methane. On paper, it worked, and at least one farmer built one, with pretty good results. Amory Lovins mentioned the idea in "Soft Energy Paths." I don't know if this has been tried again, or improved, but we need to find synergies like this wherever we can.