A Sequel to “Our Long-Term Energy Future”

Gary Banowitz, Director of Agriculture Research for the United States Department of Agriculture (DOA), addressed a large audience of farmers in Bellingham on April 17. He is based in Corvallis, Oregon. The meeting was arranged by Susan Kirch, who has a 100-acre grass farm in the Nooksack watershed of Whatcom County. She concedes that production of ethanol from corn kernels is a subsidy for corn farmers. She said, “There is a corn lobby but no grass lobby,” and she wants to change that.

Gary Banowitz explained that Washington state produces more grass seed than any other state. The industry produces a great deal of straw as a by-product. For years the straw was burned to get rid of it, but the fires polluted the atmosphere to such an extent that the government prohibited burning except in special circumstances. A fraction of the grass straw should be left on the fields to replace minerals taken from the soil and to reduce soil erosion. That still leaves thousands of tons of grass straw to be disposed of. Moreover, the federal government, concerned by oil depletion and unreliability of foreign oil supplies, wants to produce more alternative biofuels in the United States. The U.S. Department of Agriculture, under the direction of Banowitz, is endeavoring to do that.

Banowitz concedes that there is economy in size, but that is more than offset by transporting straw from scattered farms to a large straw processor. He says that each farm must have its own straw processor. That is the objective of the research under his direction.

Plant stems and leaves have cellulosic fibers difficult to convert to alcohol. The common process is mechanical breaking followed by treatment with enzymes to break the cellulose into sugars to make alcohol. Banowitz contends that the process is not practical for small-scale plants on grass farms. Instead, he is directing research to develop a small scale, farm-size processor that would gasify one to two tons of straw per hour and convert the gas to alcohol, mostly ethanol, by use of catalysts. Several catalysts are under consideration. One is nickel. As an alternative to producing ethanol, the gas could be used to run a generator that makes electricity. No explanation was given on how that would be done.

The first step of the small-scale straw processor would be to cut the straw into more or less one-inch lengths. The gas would be produced in a controlled burn, smoke but no flame, achieved by using steel balls (ball bearings) heated by steam to control the temperature. Currently, natural gas is used for the primary source for generating heat. Stems and leaves of plants have cellulosic fibers that contain silicon (some plants more than others). A controlled burn is necessary because silicon becomes glass if it is very hot.

Pyrex glass found in most kitchens would be a close comparison, but those in grass would be particulates. Unless avoided or removed, particulates would plug the catalytic converter and/or damage gasoline engines. The catalytic converter is nano technology, very small openings through which the gas passes at high velocity. That must mean gas under high pressure, but no explanation was given of how that is done.

Several factors, in addition to the distance straw must be transported to the biofuel plant, affect economics. Automation would reduce labor costs. Currently, automated feeding of straw into the machine is being researched. How often the machine must be cleaned and repaired, and how long it will last before it wears out, will not be known until the farm-sized machines are used. If the machine could be mounted on a trailer to be towed from farm to farm cooperatives that would reduce investment cost per farm, would make liquid fuel from hay more profitable. However, cooperatives would need to find a way to assure that hay is preserved in usable condition while waiting to take a turn in using the processor.

Straw from cereal grains and grass, raised specifically for biofuel could be processed in a machine designed for use on individual farms. Moreover, a member of the audience proposed raising grass for fuel on marginal lands not used for other purposes. A very strong protest was voiced by a member of the audience when Banowitz recommended raising reed canary grass, Phalaris arundinacea, to produce biofuel. Reed canary grass is the bane of restoring salmon runs in local rivers and creeks. Moderation is correct in most things. Deliberately growing reed canary grass in Washington west of the Cascades is going much, much too far. Anyone who cares about salmon and who has worked year after year to restore salmon runs knows that. Members of the Nooksack Salmon Enhancement Association know that.

Banowitz stated that the farm-sized machine to make straw into biofuel will require two to five years and $25 million. He said that the public would be informed of the economics after the machine had been used. I stated in response at the meeting that the best engineer I had ever known told me that he never checked figures computed by someone else. He always did the calculation in a different way. In this case, the other way is energy balance, energy put in versus energy put out, energy from fossil fuels used versus energy from biofuels produced.

I believe that Banowitz and colleagues are nowhere near completing a workable small straw processor that produces ethanol. I believe that a $25 million subsidy of rooftop solar systems that produce electricity would be more in the public interest. Electricity could make hydrogen. Only when we have adequate means to make hydrogen will we be in the hydrogen age and achieve fuel independence. §