Wednesday, September 23, 2009

Swimming in Ethanol's Ethos

The Arizona Chemical wood pulp mill in Panama City, Florida sits within a stone's throw of the Gulf of Mexico.

Hey there TPG readers, CHECK THIS OUT!!! This article has been translated to Hatian Creole.  I am both flattered and impressed at this unsolicited dissemination of TPG material. Quite cool :)

By Kristopher Hite

Walking on a balance beam, the idea of ethanol powering America's future took a shove from the scientific community this week. A new study published in the Journal of Environmental Science and Technology indicates that no matter the starting material whether it be corn kernels or wood chips, switch grass, and corn stover (all forms of cellulose), the environmental impacts of more ethanol, and other so called biofuels, in the gas tanks of America will mean increased environmental damage. Specifically, this study discusses the expanding "dead zone" in the Gulf of Mexico. Nutrient run-off from increased farm fertilizers being applied to crops throughout the Midwestern United States will drain into the gulf and cause larger algal blooms. This, in turn, will rob the water of dissolved oxygen killing fish, crustaceans, and other gulf-water inhabitants.

Here we have a case of clashing federal mandates. The EPA has required that steps be taken to reduce the size of the Gulf's dead zone while congress passed the Energy Independence and Security Act (EISA) in 2007 which requires the production of 36 billion gallons of biofuels by 2022. These two orders just will not jive with current agricultural practices.

Multinational biofuel manufactures are sitting pretty with the current federal mandate written in the fine print of the EISA but the citizenry need access to the knowledge buried in this recent paper to hold these companies accountable for the their potential environmental impacts. To the credit of cellulose-derived ethanol the amount of nutrients running off into the gulf would be reduced by 20% if all ethanol were to be derived from cellulose vs. corn. But either scenario will undoubtedly kill more organisms living in the gulf and increase the area of the dead zone.

Ethanol as a fuel source for transportation, home heating, and industry continues to be a double edged sword. After taking flack for driving up tortilla prices in Mexico there was a shift to talking up cellulosic ethanol in lieu of corn ethanol, but with evidence like this being presented it makes the process a harder sell. But who needs to make a sale when you've already made a long term deal with the feds?

From an applied research side I am encouraged to seek out the cutting edge of cellulosic ethanol manufacturing technology so that mandated production is done in the least wasteful way. This research lays inside fungal genomes. Scientists continue improving enzymes produced by millions of years of evolution by tweaking the amino acid sequences and increasing efficiency and stability of some very useful enzymes, in the case of deriving ethanol from the woody parts of plants (cellulose) these enzymes are called cellulases. They break down the long chains of linked sugars that constitute cellulose. By manually changing the single amino acids and then testing thermal stability and conversion efficiency scientists are able to make the process of ethanol production more efficient. Recent research in the Journal of Biochemistry reports this process in action. By demonstrating that single amino acid substitutions, in the context of a chain of hundreds of amino acids, can stabilize enzymes dramatically a group from Cal-Tech proves that human manipulation of genes can, in fact, improve the efficiency of our transition to a home-grown renewable energy economy. The Carnot's and Tesla's of this age are hard at work at this biochemical frontier.

I am torn on this issue as I can see two futures coming of all this. One in which we have attained energy independence and are free to refine our energy equilibrium to the point of balance with the ecosystems in which we live. Or the other where our environment has completely eroded and we have no choice but to fight amongst each other for the scant resources still available. The technologist in me says "onward" while the environmentalist says "onward, but mindfully." In either scenario the ideal of efficiency is a positive one that can be easily applied locally by individuals adopting more mindful habits.

Note:  This blog post was picked up by an editor at SEED magazine and turned into and e-cover story - The Dead Zone Dilemma.   In this article Dave Munger questions my optimism and my advocacy as a scientist. In so doing he is questioning some basic tenets of scientific inquiry.

He asks - "Shouldn’t scientists just be interested in giving us the facts, staying removed from policy decisions and letting the general public and politicians decide how to act? Doesn’t becoming an advocate introduce bias into the scientific process, potentially tarnishing results?"

After contemplating these questions I responded in a post titled "Should Scientists Speak their Minds?"

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Heinzelman, P., Snow, C., Smith, M., Yu, X., Kannan, A., Boulware, K., Villalobos, A., Govindarajan, S., Minshull, J., & Arnold, F. (2009). SCHEMA Recombination of a Fungal Cellulase Uncovers a Single Mutation That Contributes Markedly to Stability Journal of Biological Chemistry, 284 (39), 26229-26233 DOI: 10.1074/jbc.C109.034058
Costello, C., Griffin, W., Landis, A., & Matthews, H. (2009). Impact of Biofuel Crop Production on the Formation of Hypoxia in the Gulf of Mexico Environmental Science & Technology DOI: 10.1021/es9011433
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