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Through generous subsidies from the US government, secured by corn-belt politicians, 25% of America’s corn (maize) crop is turned into ethanol for use in automobiles. Ignoring the negative impact this has on food production, agricultural runoff and land use, there is new talk of raising government mandated fuel mixture proportions to use even more ethanol. At the same time, the idea of turning farm and forest wastes into “cellulosic” ethanol, a biofuel to power cars and trucks continues to languish. Because of the ongoing economic slump, a plentiful supply of ethanol made from corn, and uncertainty among policymakers, companies have delayed plans to build commercial-scale cellulosic ethanol plants, some canceling them altogether. Evidently, even the hundreds of millions of dollars on offer from the Department of Energy (DOE) are not enough to lure investors to participate in this latest biofuel boondoggle. Industry understands what biofuel advocates do not—biofuels make no sense in terms of energy policy: neither environmentally nor economically. Instead of propping up wasteful and nonviable biofuel schemes, Congress should stop all biofuel subsidies and kill all ongoing ethanol projects.

Though the wrong headed “cap and trade” bill has been derailed in the US Senate, the specter of energy legislation is once again rising. As the energy debate heats back up, the journal Science has dedicated its August 13, 2010, issue to the subject of alternative energy. Writing in the introduction, David Malakoff, Jake Yeston, and Jesse Smith identified the heart of the alternative energy problem:

The end of the age of fossil fuels may be in sight, but what comes after is still a bit of a blur. There are numerous alternatives to coal, oil, and natural gas from electricity generated by solar farms to biofuels brewed from plants. Scaling up these alternative sources of energy, however, has proved a challenge.

Case in point, the US government’s plan to reduce the nation’s dependence on oil by scaling up cellulosic ethanol is in deep trouble. The complex technical, economic, and political forces involved in efforts to create viable alternatives to fossil fuels have proven close to insurmountable. Domestic biofuel production is only kept flowing with liberal application of government dollars. “In the current financial climate, existing federal policies are simply not enough to encourage the investments that will make these fuels a reality,” says Jeremy Martin, a chemist with the Clean Vehicles Program of the Union of Concerned Scientists (UCS), in anews article in Science.

According to Robert F. Service, a writer for Science, the plan to build an American biofuels industry on cellulose has stalled out after a promising start. In 2005, the US Congress approved new rules mandating a steady ramp-up in biofuels use. By 2022, cars were to be burning up to 36 billion gallons (136 billion liters) of biofuel a year, equivalent to one-quarter of today’s US gasoline consumption. Early on, this was to come from “first-generation” biofuels, primarily ethanol made from corn. Corn ethanol production has grown steadily from 3 billion gallons in 2005 to 12.1 billion gallons this year. Most is blended with gasoline in a 10% ethanol to 90% gasoline mix, since higher proportions of ethanol can cause damage to car engines and fuel systems not specifically designed to run on alcohol.

Energy legislation from 2007 mandates an increasing share of cellulosic ethanol (dark green).

But even the US Congress is incapable of turning corn ethanol into a positive proposition. Investigations by the US EPA, the California Air Resources Board (CARB) and the EU’s joint Research Council all reported that biofuels pollute more than the fossil fuels they are supposed to replace, leading researchers to conclude that it would be better to simply burn the crops rather than convert them to biofuels. Add to that excessive water use in creating biofuels and the green luster of these fuels fades significantly. Again, according to Service:

Congress, however, has capped the amount of corn ethanol it wants in gas tanks at 15 billion gallons by 2015. In part, that’s because making corn ethanol is energy intensive, so the fuel doesn’t do much to offset fossil fuel use or lower greenhouse gas emissions. Beyond that first 15 billion gallons, policymakers envisioned biofuels coming from “advanced” sources, such as ethanol and gasoline-like hydrocarbons made from plant materials high in cellulose.

The ramp-up in cellulosic ethanol production, however, is already well off track. Demonstration facilities are expected to turn out up to 25.5 million gallons this year—far below the 250 million gallons that the U.S. Environmental Protection Agency (EPA) once wanted fuelmakers to produce. In a telling sign of cellulosic ethanol’s struggles, over the last year the agency twice scaled back its expectations after it became clear that the industry wouldn’t be building commercial-scale plants as quickly as once thought.

Part of cellulosic ethanol’s problem is technological—converting cellulose into alcohol is simply not as easy or efficient as brewing up a batch using corn or sugar cane. When starting with a feedstock rich in simple sugars, such as Brazilian sugar cane, making ethanol is a mater of using yeast to convert sugar to alcohol—a process similar to making beer or wine. In the US, where corn it the feedstock of choice, the process is slightly more complex. Enzymes must be used to break down the starch in corn kernels into its component glucose molecules, which yeast can then digest.

The task becomes even more difficult when using cellulosic feedstocks such as switchgrass, corn stalks, or wood chips. The sugars in these materials are locked in cellulose, hemicellulose, and pectin, which are polysaccharides like starch but much harder to break down, and lignin, which crosslinks different plant polysaccharides. Breaking these biopolymers into simpler compounds that can be converted into ethanol remains a difficult problem. While fermentation converts about 90% of the energy in simple sugars to ethanol, converting cellulosic feedstocks to ethanol yields just 40% of total energy content. That means cellulosic ethanol plants need far more raw material than first-generation plants do to make the same amount of ethanol.

While researchers are confident that the yield for cellulosic conversion will be improved in the future, it remains uncertain that better yields can revive the moribund ethanol market. The US uses a total of about 140 billion gallons of gasoline a year. Mixed with gasoline at a 10/90 ratio, the demand for ethanol is only about 14 billion gallons. First-generation plants are already making 12.1 billion gallons of corn ethanol annually, and idled plants are capable of boosting the total to 15 billion gallons. The result is that the industry has reached a “blend wall.” In the words of Wally Tyner, an agricultural economist at Purdue University: “There is no room for cellulosic ethanol.”

Cellulosic ethanol costs are equivalent to oil at $120 a barrel, well above oil’s recent price around $75 a barrel. At these prices, there is no motivation to ramp up cellulosic ethanol production. The ethanol glut and economic problems not withstanding, the EPA is considering increasing the required amount of ethanol in blended fuels to 12% or even 15%. Since such fuel could damage older cars, the idea doesn’t have much appeal. Another idea is to mandate that future autos be able to run on an 85% ethanol blend, so called E85 fuel. Neither step would raise demand above existing corn ethanol production capacity in the near term.

Currently, the ethanol tax credit pays fuel blenders a flat $0.45 for each gallon of ethanol they use. Another proposed “solution” would be to offer larger credits for cellulosic ethanol. Most of the existing $6 billion a year in ethanol subsidies and tax credits are currently up for renewal by Congress. Lawmakers have already allowed one tax credit for biodiesel to lapse, adding to investors’ worries that ethanol subsidies could be next. The prospect of radical belt tightening by Congress could be a deathblow for cellulosic and corn ethanol fuel subsidies—and it wouldn’t come a moment too soon.

Also in the special issue of Science, Richard A. Kerr, writing in an article titled “Do We Have the Energy for the Next Transition?” notes that during past energy transitions humanity has always moved to a better fuel. “Never has the world so self-consciously tried to move toward new sources of energy,” he states. “But the history of past major energy transitions—from wood to coal, and from coal to oil and gas—suggests that it will be a long, tough road to scaling up alternatives to fossil fuels that don’t stoke greenhouse warming.”

In the 1800s, wood and animal feed provided more than 95% of humanity’s energy. Since then world energy use has increased twenty fold. Replacing even half of the coal, oil, and gas consumed today would require 6 terawatts of renewable energy. Plus, the transition from coal to oil in developed nations took more than half a century—there is little reason to expect the move away from fossil fuels will take less time. This is complicated by the fact that wind, solar and biofuels in particular are demonstrably inferior energy sources than oil and coal in terms of transportation, convenience and energy density.

Fossil fuels each took half a century to dominate energy production.

“We are confronted with a society built on high-quality energy, dense forms of energy, fossil fuels especially,” states ecological economist Cutler Cleveland. “Could you have the same standard of living with renewables? I don’t think we really know. Things might have to change very fundamentally.” The question we have to answer as a society, as a civilization, is does perusing renewables like biofuels make sense or are we headed down the road to ruin? This is not to say we should ignore other forms of real pollution or the world’s looming energy gap. But trying to avoid the global warming boogieman may be causing bad decisions that will leave things in worse shape for our children and grandchildren.

The world is not yet running short of fossil fuels, the US alone has 200 years of coal and almost 100 years of gas reserves. Oil will not “peak” until 2030, if then—all past predictions have proven wrong. As we said in The Energy Gap, fossil fuels will be needed by our energy hungry world for the foreseeable future. Even though humanity will eventually need to transition from fossil fuels, what is needed is a better source of energy, not a poor substitute like biofuels.

It is a confusing challenge, trying to sort the good from the bad alternatives, which is why we wrote TEG. Pick up a copy and find out how to solve the world energy crisis, preserve the environment and save civilization. In the mean time, tell our political leaders to kill biofuel subsidies—they are a bad deal for everyone.

Be safe, enjoy the interglacial and stay skeptical.

The Resilient Earth, 29 August 2010