Commercial Scale Cellulosic Ethanol Arrives—Finally

The question of biofuels as an energy source has probably generated more heat than light. It has also powered a great many vehicle miles that otherwise would have been powered by gasoline. Whether you consider that a good thing or a bad thing will likely determine your position on the issue.

Conservatives dislike biofuels because they represent a large government program and because they pose a genuine threat to one of their biggest supporters, the oil industry. Liberals dislike them because they are the legacy of George W. Bush and because of their inherent distrust of industrial agriculture which benefits greatly from the commitments that have been made.

While these facts are all true, they are more distractions than anything to do with the crux of the matter. Clearly, the issue is complex enough to merit an entire book, but let me just focus your attention on what is happening right now.

The oil industry lobby works tirelessly to protect the hundreds of billions of dollars of profits that their sponsors receive every year. Sensing an opportunity in the public’s combination of confusion over and dislike of ethanol, they have gone on the offensive, asking the EPA to back off on the amount of ethanol mandated under the Renewable Fuel Standard (RFS). The EPA has listened and as of December, they have reduced the amount of ethanol that must be produced by 1.34 billion gallons, a reduction of roughly 8%. Further greater reductions of as much as 40% are on the table and will be decided in June.

While it’s true that there is much to dislike in the corn ethanol program, including its energy intensity, competition with food, and relatively small net energy benefit, not to mention the fact that we are now producing far more gasoline domestically via fracking and other questionable means, there is a sustainable gem at the heart of the program. That gem, known as cellulosic ethanol, uses non-food sources, such as agricultural residue, trash, wood chips and forest trimmings to make fuel. These fuels represent a far better ecological bargain than corn or any other food crop. The reason we went with corn at first was because we know how to grow lots of corn really well, and we’ve known how to make alcohol out of corn since the days of the moonshiners. The reason we didn’t start out making fuel out of wheat straw, or corn stalks or other crop wastes was because we didn’t know how. Many years and millions of research dollars later, studying everything from enzymes to embryogenic cell cultures, cellulosic ethanol is on the verge of becoming prime time. This could turn out to be a really bad time for the government to withdraw its support. Doing so now could be like throwing out the baby with the bath water.

Abengoa Bioenergy, a Spanish company, is investing $500 million in a plant in Kansas that will produce 25 million gallons of ethanol per year from crop wastes. The plant, which will be operational next month, will be powered by a 21 MW electric generator that will also be powered from biomass. That plant will be followed later in the summer by a plant of similar size in Emmetsburg, Iowa by the South Dakota-based ethanol producer Poet, in partnership with the Dutch company Royal DSM. Those two plants will be followed by a 30 million gallon plant DuPont that is underway in Nevada, Iowa, that will also be using corn waste.

Research has been critical to reach this level. Abengoa has developed a proprietary enzyme that have helped to increase the yields from 55 to 80 gallons per ton.

While the combined 80 million gallon annual output of these three plants, might sound like a lot, it is tiny compared to the total of 14 billion gallons of ethanol that has been mandated under the RFS. That is exactly the problem. These companies, after convincing investors to cough up hundreds of millions of dollars to get to the point where they are just beginning to achieve scale, are now being faced with a potential withdrawal of support by the government, a move that could convince investors to drop everything and head for the hills, just as the industry is finally beginning to turn the corner to a truly sustainable mode of operation. In investment circles, this stage, when a new venture is just shy of reaching full scale and is still totally dependent on investment dollars, is known as "the valley of death" since so many fail at that stage. The Biotechnology Industry Organization estimates that it will take some $95 billion or more in private investment over the next decade to scale up to meet the expectations of the RFS.                                                              

Cellulosic ethanol can be used in conjunction with corn ethanol, with the corn going down one production line while the cobs, leaves, and stover go down another. This substantially increases the level of fuel produced by the same land, water and fertilizer inputs that had previously been used to produce the fuel from the corn alone. It’s really just a way of using the entire corn plant more effectively (some is still returned to the soli for tillage), not unlike the Native Americans once did with the buffalo. Alternatively, the corn could be used for other purposes, including animal feed, industrial feedstock, or whatever else you want to do with corn. The key point in that the production of cellulosic ethanol from plant materials that were either being grown anyway or being discarded, resolves just about all of the issues that people have had with corn ethanol. And as a matter of public policy, the Fuel Renewable Standard has wisely capped the amount of ethanol that can be produced from corn, a cap that has essentially been reached. This means that essentially all additional growth in biofuel will be of the cellulosic variety, which is a good thing.

Remember, the CO2 given off when bio-ethanol is burned, was only recently pulled out of the atmosphere, so it’s inhale-exhale, not net carbon added to the system. The CO2 given off when gasoline is burned had been buried for millions of years underground where it had not been impacting our climate. Burning those fuels will be introducing new carbon into the system. When we’re talking about billions of gallons, that could be all the difference in the world.

{Image credit: Great Lakes Bioenergy Research Center: Flickr Creative Commons]