Aug 22

Manure: making ethanol efficient!

Last week Husky Energy Inc. announced that its ethanol plant in Lloydminster, Saskatchewan, will be producing within weeks and should reach peak production by the end of the year.

Ethanol, a.k.a. ethyl alcohol, is a renewable fuel source distilled from biomass—typically wheat, sugar, corn or soybeans. It can be blended with gasoline to reduce the use of fossil fuels and minimize pollution.

The Lloydminster plant will produce 130 million liters of ethanol annually from 350,000 tonnes of wheat. That begs the question: just how much fossil fuel is really being saved when you factor in the gasoline and diesel that powers the equipment used to grow and transport that wheat and fuel the ethanol factory itself?

Critics contend that in fact traditional ethanol production consumes nearly as energy in the form of fossil fuel as it produces in the form of renewable fuel.

But the key word in that sentence is “traditional.” As National Geographic News recently highlighted, there are new ethanol plants using a very non-traditional and highly renewable energy source to power the ethanol process: cow manure.

Hereford, Texas (just an 80-kilometre drive from Tulia, Texas, where I lived as a kid) is a cattle town. And that means, as Todd Carter, CEO of Dallas-based Panda Energy, puts it, “There are literally mountains of manure.”

Panda plans to extract methane from 453,000 tonnes of manure each year (produced by about 500,000 cows) and burn it to produce the steam necessary for processing corn into 378 million liters of ethanol. Panda expects to save the equivalent of a thousand barrels of oil a day. Best of all, the manure is free: feedlot operators have to dispose of it anyway.

Another company, E3 Biofuels, headquartered near Kansas City, is taking things a step further. This fall, it plans to begin operating a “closed loop” plant that will combine a feedlot with an ethanol plant.

Manure that falls from cattle kept in long barns with slotted floors will be pumped directly into the methane-extracting facility. This saves the cost of collecting and transporting the manure and prevents the atmospheric release of methane, a powerful greenhouse gas, from slowly decomposing manure into the atmosphere.

E3’s plant will break down manure inside an anaerobic digester, a device in which bacteria attack the manure in the absence of oxygen, producing both methane and (another bonus) an ammonia by-product that can be sold as fertilizer.

The plant, built around an existing feedlot, will use the manure from 30,000 cattle a year to produce 91 million liters of ethanol from locally grown corn. One by-product of the ethanol process will be protein-rich wet distillers’ grain, which can be fed back to the cattle.

E3 has high hopes for its closed-loop system. Their CEO, Dennis Langley, says that while a traditional ethanol plant takes one BTU of energy to produce ethanol containing two BTUs of energy, each BTU of energy used by E3’s closed-loop plant will produce ethanol containing 46.7 BTUs; or, to put it another way, that producing 3.8 liters of E3 ethanol is equivalent to producing 87 liters of traditional ethanol, or 57 liters of gasoline.

Some ethanol skeptics are skeptical that the difference will be that great, but admit that the E3 approach just might swing the questionable energy balance of ethanol production in ethanol’s favor.

Just in time, too. The U.S. passed an energy bill last year that called for increased ethanol production. That’s one reason E3 wants to build three to five new plants every year from now on, and Panda already has plans to build its versions of manure-powered ethanol plants in Haskell County, Kansas, and in Yuma, Colorado.

Saskatchewan, of course, was the first province in Canada to pass a law requiring ethanol in its gasoline; eventually the requirement will be that the gasoline sold by distributors must contain an average of 7.5 percent ethanol.

With that requirement, the province will use about 125 million litres of ethanol per year, mostly (thanks to the Lloydminster and other new plants currently being built) produced from our own wheat.

Too bad we don’t have mountains of manure lying around like Hereford, Texas, to help fuel the new ethanol plants.

But you can’t have everything. And besides, this is Saskatchewan: we don’t do mountains.

Edward Willett

Permanent link to this article: https://edwardwillett.com/2006/08/manure-making-ethanol-efficient/

1 comments

    • Walrus on August 22, 2006 at 9:35 pm
    • #
    • Reply

    You mean Mount Blackstrap doesn’t COUNT?

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