Friday, February 08, 2008

Fie on Corn Ethanol

Results from a recent study of ethanol suggest the widely touted biofuel could actually ADD to global warming. The study was completed by a consortium of researchers from Princeton University and several of institutions and published in Science Magazine.

The reasoning is that more land will be put into crop production, principally corn, sugar and switchgrass to satisfy building demand for ethanol feedstock. In the U.S., current plans are to increase ethanol production to 36 billion gallons a year by 2022.

The study appears to focus on the carbon impact of removing land from fallow or forest would reduce the carbon-absorbing property of the land. This reduction in carbon-absorption was not previously included in calculations of the benefits of ethanol.

Naturally, the proponents of ethanol, like the Renewable Fuels Association, are crying foul and making counter claims of over simplification.

The replacement of fossil fuels with renewable energy sources is not a simple equation. I suspect even the Princeton study left out the carbon impact of irrigation water and fertilizer, two very necessary inputs to corn production.

In the Spring 2007 planting season, U.S. crop producers made dramatic shifts in acreage, most of which agriculture experts say were motivated by rising corn-based ethanol production and high corn prices. There was a 17 million acre increase in feed grain production, of which 15.3 million went to corn plantings. A portion of the increase was accommodated by a reduction of 11.9 million acres of soybean plantings, a reduction of 1.3 million acres of spring wheat and 4.4 million fewer acres of cotton.

The rest of the feed grain acreage expansion came from a four million acre increase in total planted acreage. This means that land which had been in fallow, grassland or forest, was plowed up for grain production - corn - that was eventually burned up in someone’s SUV.

A few plants, a bit of water and some sunlight create a “carbon sink.” Currently, plants on the land and under oceans absorb about half of the man-made carbon dioxide in the world. Unfortunately, the world carbon sink has a capacity limit, i.e. we cannot reduce its size and still expect half our CO2 output to get processed.

So what value is four million acres of “carbon sink” land? That is less than 1% of the total continental U.S. land mass. Scientists at NASA’s Earth Science Enterprise have been noticing that the U.S. terrestrial carbon sink has been increasing the last couple of decades. This is due in part of forest re-growth. If we change the land use to a purpose that actually increases CO2 emission, even four million acres becomes significant.

There is economic value in land beyond agriculture production. For example, there are 36.8 million acres enrolled in the Conservation Reserve Program (CRP) administered by the U.S. Department of Agriculture. The voluntary program is aimed at helping farmers enhance environmentally sensitive land to improve water quality, control erosion and build habitats for waterfowl and wildlife. Instead of planting crops, farmers receive CRP payments averaging $50 per acre. The CRP program is largely credited with producing and sustaining millions of ducks and grassland birds like the pheasant in the so-called prairie pothole region in North and South Dakota.

If any there is any doubt about the economic value of these wild birds note that the ten-week pheasant hunting season in South Dakota brings in an estimated $110 million in tourism dollars to the state’s economy each year. The added plus is that pheasant habitat can double as a carbon sink.

I do agree with the Princeton study on one point. There is a strong case for waste as a feedstock instead of a planted crop. Indeed anything organic can be used for ethanol or biodiesel. Even the pheasants could endorse that plan.

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