Closed-loop energy system shows potential

Tuesday, January 23, 2007

One's man trash is another man's treasure.

Or, in this case, one creature's -- well, something worse than trash -- can make a new energy system more efficient and economically viable.

As you probably noticed in your recent gas bill, the price of energy is going up, even without this winter's frigid temperatures and snow.

Now imagine the amount energy you would need to operate a huge ethanol plant like those springing up around Southwest Nebraska.

In fact, the amount of fossil fuel needed to produce energy in the form of ethanol has always been a sticking point -- whether creating a gallon of ethanol might actually take more fossil fuel than it creates in renewable energy.

The Renewable Fuels Association, a national trade association for ethanol, says the ratio is positive, with about 1.67 units of ethanol energy produced for every unit of fossil-fuel based energy. Others say the ratio is more favorable, as much as 2.5 units of ethanol energy for every unit of fossil fuel.

Now a new system in Mead promises to take even more fossil fuel out of the equation.

In a new closed-loop system set to begin operation next month, some 244,000 tons manure from a 28,000-head cattle feedlot will be used to produce more than enough methane to power a 25-million-gallon ethanol plant.

And, brewers' grain from the distillation process can be fed back to the cows, completing the cycle.

Not only will it produce energy in the form of ethanol, it will prevent greenhouse gases from the cows from escaping into the atmosphere. In addition, producing methane on site instead of buying natural gas, can save the plant millions of dollars a year.

Kansas-based E3 BioFuels, builder of the Mead plants, has a goal of completing 15 such plants over the next five years.

With feedlots in abundance and a couple of dairies, the McCook area and Southwest Nebraska seem like prime spots for trying out such a closed-loop system.

And, manure isn't the only potential source of methane. We have to wonder how much energy could be captured from McCook's grass-composting site, or even from drilling a well into the old landfill site at U.S. 6-34 and Highway 83.

Or, maybe we should consider getting back into the landfill business to generate energy, rather than spending money to pay for the energy to haul our solid waste away from our area.

Perhaps methane and ethanol could be a winning energy combination for Southwest Nebraska.

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