The Secondary Effects of Switchgrass Cultivation

I heard an interview the other day with Ken Vogel about his research on the efficiency of switchgrass cultivation for ethanol production and thought you might want to take a look at the Scientific American article about it (hat tip: Glenn Reynolds). This largescale, painstakingly detailed study has demonstrated that switchgrass is an enormously more efficient method of producing ethanol than corn:

But yields from a grass that only needs to be planted once would deliver an average of 13.1 megajoules of energy as ethanol for every megajoule of petroleum consumed—in the form of nitrogen fertilizers or diesel for tractors—growing them. “It’s a prediction because right now there are no biorefineries built that handle cellulosic material” like that which switchgrass provides, Vogel notes. “We’re pretty confident the ethanol yield is pretty close.” This means that switchgrass ethanol delivers 540 percent of the energy used to produce it, compared with just roughly 25 percent more energy returned by corn-based ethanol according to the most optimistic studies.

They’ve taken everything into account in their calculations: the energy used to transport the seed, the energy used to plant, fertilize, cultivate, and harvest the switchgrass, the energy used to produce its fertilizer, the energy used to transport the switchgrass, the energy used to make ethanol. With brain-numbing attention to detail.

I suspect there will be a battle over current corn subsidies which, rather obviously, should be eliminated. We shouldn’t encourage corn cultivation for ethanol production when there’s a significantly better alternative available but, equally obviously, those receiving the subsidies will want them to continue.

The first secondary effect of largescale switchgrass production that we might consider is that it’s likely to raise the value of Midwestern farmland, particularly in the upper Midwest. Land values in North and South Dakota have languished for decades but we may see this changing. And the land is certainly too valuable to pave over or build housing tracts on.

Another secondary effect is that corn prices are likely to stabilize or even fall as demand for corn for ethanol production deteriorates. That may result in reduced revenues for hybridizers like Pioneer (now owned by Dupont).

10 comments… add one
  • PD Shaw Link

    What’s not clear to me from reading the Scientific American article is how the use of switchgrass would stop the displacement of food crops with fuel crops. They emphasize that switchgrass can be grown on more marginal land, but I would imagine that if the infrastructure for switchgrass was put in place, then there would be a demand for switchgrass that would attract farmers currently cultivating food.

  • For one thing it would put land into cultivation that isn’t currently being worked. As agriculture is conducted in the U. S. today the limit factor on how much is grown isn’t labor but land and capital.

    Although it’s possible that people who want to farm would be attracted back into it.

  • PD Shaw Link

    I guess what I’m getting at is that all land is not equal. An acre of prime farmland might yield ten times the crops cultivated on marginal land. One landowner has a significant competitive advantage. If we are trying to reduce the use of corn for fuel and increase the use of switchgrass as fuel, the most obvious line I draw in my head is that farmers currently growing corn will begin growing switchgrass.

  • That’s not necessarily a bad thing. Present subsidization of corn for ethanol production incentivizes overproduction of corn.

  • Wait. You’re saying there’s a North and a South Dakota?

  • Yeah, I spent a week in Fargo one afternoon several years back.

  • Don’t believe him, Michael. There is no North Dakota – that’s just Canada trying to fob off some of their frozen tundra on us. (Like we would want any.)

  • North Dakota is that state of hallucinatory boredom you reach after driving halfway across South Dakota Michael.

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