Alan Zeithamer with a tractor that runs on alcohol fuel.
PHOTO: MOTHER EARTH NEWS STAFF
It would be hard to imagine any group of people who are harder hit by fuel shortages than are this nation's farmers. And, of course, when our agriculturists—who supply so much of the world's "bread and butter"—suffer, millions of other folks share the effects in the form of high priced (or even completely unavailable) food.
But one particular granger family—the Zeithamers of Alexandria, Minnesota—is simply not about to take any "gasoline drought"—real or contrived—sitting down. These folks are making their own alcohol fuel for about half the price of the commercial gasoline it's replacing.
It's Plainly Practical
The Zeithamer dairy farm—a 50-cow, 500-acre spread—requires more than 10,000 gallons of combustible petroleum to get through each year. Increasing fuel costs were enough of a burden for the Minnesotans to contend with, but a scarcity of the precious liquid could have resulted in disaster—one reason why Archie (the senior Zeithamer) and his son Alan decided to convert to alcohol fuel, aka "farmer's fuel."
"It's nothing new, you know," Archie says. "Farmers were burning straight alcohol in their tractors years ago when they couldn't get anything else. There's no doubt it works. And no one else is better equipped to handle alcohol production than are farmers. We have the raw materials right on hand, and we're far more flexible than any large commercial distilleries could be because we can make fuel out of whatever surplus crop we have available. Furthermore, we're producing our ethanol right here where it's going to be used. We aren't burning up half our product trying to deliver it to some distribution point located three or more states away."
The cost factor is another reason why Archie feels that on-farm distilleries are the most practical. The Zeithamers' total production plant investment was only $10,000—not an overwhelming sum for a farm the size of theirs—and the operating expenses are also minimal, since the plant is usually fired with wood scraps. The Minnesota farmers can make 500 gallons of alcohol fuel per week, which—with all expenses except labor considered—will cost them only 50¢ a gallon!
How the Alcohol Operation Works
The Zeithamers use a 4,000-gallon oil tank—mounted over a masonry firebox—as their cooking and fermenting vat, and they've equipped the container with an electrically powered agitator that constantly stirs the mash mixture while it's being heated (thereby eliminating the need to "babysit" the process in the cooking stage). The father and son team shell and grind their corn to a coarse consistency, then add it to the tank, with water, in a ratio of about 28 gallons of liquid to each bushel of corn. Yeast and enzymes are also added during the process, and the mixture is allowed to cool and ferment for about three days. The resultant "still beer" (it contains about 7 1/2 to 10% alcohol) is strained through a filter and temporarily stored in a 10,000-gallon tank which is set, underground, beneath their fermentation vat.
The Minnesotans then pump the "beer" mixture through a preheating chamber and on into their "stripper" column: a 12-inch-diameter, 17-foot vertical pipe (containing 76 perforated plates) which separates the alcohol vapors from the water mixture. This design allows for any partially distilled mash to fall back to the base of the tower to be recycled. The alcohol vapors are taken off the top of the column, fully liquefied in a condenser, and finally drained into a 1,000-gallon storage container to be denatured. (The denaturing process involves nothing more than the addition of several gallons of gasoline and ketone to the tankful of spirits in order to guarantee that the fuel cannot be used as a beverage.)
According to Alan, the Minnesota still produces 160- to 180-proof alcohol at a rate of up to 28 gallons per hour. "We could get a purer product, but we don't need it. Our equipment runs fine on 160-proof fuel, so it would be senseless to use extra energy trying to make the ethanol any stronger. As it is, we've got a very favorable balance: Our product is worth a lot more—both economically and in terms of energy consumed—than what we use to produce it."
The Gopher Staters are also in the process of designing several additional systems that will make their alcohol production plant—and their farm as a whole—more efficient. The still's waste heat—and carbon dioxide from the fermentation process—will soon be used to supply a greenhouse. AI also plans to start construction on a methane digester next year which will, of course, utilize cow manure to produce enough of the flammable gas to "fire" the still. (Other sources of heat—including corncobs, waste oil, and used tires—are also being considered, since the Zeithamers claim these fuels can be burned without causing pollution by using a water injection system.) The farm family is using the alcohol plant's DDGS (Distiller's Dried Grains and Solubles) by-products as cattle feed, too, and they're even saving water by recycling the liquid through the distilling system rather than starting fresh on each alcohol "run."
The Zeithamers see no future problems with their alcohol production (especially since the plant will pay for itself in less than four years). Meanwhile, the younger Zeithamer is also looking into the potential of potatoes as a raw material, has been experimenting with an abnormally hardy strain of yeast (which can function in a 16% alcohol mash solution), and is researching various other methods of isolating alcohol from the mash (either by using a freezing process or by adding some form of potash).
Those answers might still be a few years down the road, but it seems that the Zeithamers are doing just fine—on their own—right now!