Beyond Corn-Based Ethanol

The Brookings Institution in conjunction with the University of Iowa held an event Oct. 17 in Iowa City on energy, ethanol, and national security. Despite what one might have expected, however, this was not a rally for any and all forms of ethanol as a substitute for petroleum-based fuels.

As most realize, Congress and the Bush administration are pushing ethanol very hard right now as a way to find domestic, environmentally friendly alternatives to oil. The president’s goal is to produce 35 billion gallons of biofuel annually by 2017 (with ethanol actually only one of the possible choices, biodiesel being another). That would be a sixfold increase from today and equal, in energy content, more than 10 percent of America’s petroleum imports expected at that time.

The concept of corn-based ethanol is sound — that is, up to a point. As several of the panelists, including Jerry Schnoor, Mani Subramanian, and Tonya Peeples of the University of Iowa’s engineering schools, one of us, Steve Fales of Iowa State’s agronomy department, and John Miranowski of Iowa State’s economics department underscored, however, there are lots of downsides to pushing the corn-based ethanol concept too far. The gist of the panelists’ remarks was that it should be viewed as a transitional biofuel and not the final objective in and of itself. It can help us create markets for biofuel, refineries to make it, infrastructure (like dedicated pipelines) to move it around the country, and demand for cars utilizing it. But the real breakthrough will have to be of a different type.

As Jerry Schnoor emphasizes, when you put a gallon of Iowa ethanol in your flex-fuel vehicle, you’re also effectively putting several pounds of Iowa topsoil into the Mississippi River and ultimately the Gulf of Mexico. That is because plowing fields for annual crops inevitably creates substantial erosion — not to mention the usual pesticides and fertilizer runoff characteristic of intensive agriculture.

Most of Iowa’s potential farmland, about 23 million acres, is already devoted to corn and beans. The popularity of ethanol may, however, lead farmers to cultivate an additional 1 million acres now in the conservation reserve program, with associated environmental consequences.

While growing corn for ethanol production in Iowa can be done without irrigation, doing so in the dryer Plains states cannot. Using modern methods, It takes about 2,000 gallons of water to grow a bushel of corn. The Plains states were already depleting their water tables unsustainably before America’s recent ethanol trend took root, meaning they have little room for further expansion (in fact, they have no real capacity for expansion).

Corn-based ethanol now produces more energy than is required to produce it. So its net effect on energy balances is positive and desirable. But it does require fossil energy to produce — in the form of fertilizers, diesel fuel for tractors, and more often than not the fuel to operate refineries. On average, corn ethanol only yields about 30 percent more energy than is consumed in production. This efficiency is improving all the time, but not enough to make corn ethanol the real biofuel of choice for the longer term.

In addition, the United States has about 450 million acres of farmland of all types under cultivation today. Up to 100 million acres more would be needed to reach the president’s goal using corn-based ethanol. It will be impractical to find that much new farmland; substantial amounts of food crops from existing farmland would have to be displaced to do so. The alternative is to use some other raw material.

Thankfully, we already know what we have to do. Importing more ethanol made from sugar cane in places like Brazil is part of the answer (though we need to get the economics right so American ethanol producers are not displaced by cheaper ethanol made abroad). Cellulosic ethanol is the real key. It is made from plant biomass — be it prairie grass (perhaps helping give Iowans their elusive third crop after corn and soybeans, as well as permitting more arid states to contribute as well), poplar and other such soft woods, cornstalks, or even algae, depending largely on which part of the country is at issue, and its agricultural advantages.

To be economical, producing large amounts of cellulosic ethanol will require further advances in microbiology that have given rise to the kinds of enzymes needed to break down its complex structures into simpler molecules. That process is well under way. Advances will also be needed in increasing sustainable plant yields to supply enough biomass.

Cellulosic ethanol may need subsidies to be economical for a time — it’s a brand-new industry. But it will produce huge net benefits in terms of energy security eventually, quite likely going well beyond existing ethanol goals for 2017.

Unlike its corn-based cousin, cellulosic ethanol is estimated to provide anywhere from 3 to 8 times as much as energy as is required to make it. And a great deal of land presently underutilized could be dedicated to this purpose.

Materials for biofuels can be produced in virtually every region in the nation in one form or another. This will make it possible to create an industry with many players, and will foster energy security by distributing production and risk over a wide area.

The next American president will have to work hard to master the economics and technology of biofuels. We are in a transition in which selective use of government support can make a critical difference — through research and development, subsidies for buying alternative-fuel cars (which can also be made to plug in to the electricity grid), and certain mandates on the energy industry such as Brookings scholar David Sandalow and Indiana Republican Sen. Richard Lugar’s idea of requiring a large fraction of gas stations owned by major energy companies to have ethanol pumps within a few years. (Mr. Sandalow also participated at the Iowa panel. See his new book, Freedom From Oil, for more.)

We also need to emphasize more efficient use of energy, of course; increased production cannot suffice, even if done in an environmentally friendly way.

Today’s corn-based ethanol movement has its place. But it is time to move beyond it, and the next president will be ideally positioned to do so.