• Energy & Power

Ethanol: Separating Fact from Fiction

When energy prices soared during the 1970s, most Americans recognized the inherent danger in the U.S.’s dependence on imported petroleum. Despite current complacency, the potential economic and national security threats have not diminished. In 1995 the United States exceeded the level of imported petroleum it reached during the 1970s. Today, in fact, more than half the petroleum-based energy used by our industries and auto-mobiles is imported.

The 1970s provided an economic wake-up call, but the ensuing 20 years brought another important issue to the energy debate. Engine emissions contain a host of pollutants that adversely affect the air we breathe and contribute to increasing levels of in our atmosphere.

In the search for solutions, renewable fuels quickly emerged as desirable alternatives to petroleum products. One of those renewables is ethanol, which directly displaces imported oil, greatly reduces tailpipe emissions of some of the most dangerous pollutants, and helps bolster the agricultural economy.

Currently, most ethanol is derived from field corn. New techniques developed by researchers show that ethanol can also be produced from other “biomass” sources such as corn stover, pulpwood, rice straw, , food processing waste, and even municipal solid waste.

Despite the positive aspects of ethanol’s use as a transportation fuel, many misconceptions concerning its performance and production persist.

Ethanol at a glance

  • Reduced engine emissions
  • Proven engine performance
  • Economic stimulation
  • Made from a variety of renewable materials
  • Produces more energy than it uses

Fiction: Ethanol does not work well in conventional vehicles

Fact: Ethanol is a proven performer in internal

Ethanol blends have been approved for use by every automobile manufacturer that does business in the United States. A primary advantage of ethanol for engine performance is octane enhancement: a 10% blend of ethanol in raises the octane number by 2.5 points.

Years ago, when ethanol blends were first marketed, fuel line freeze-up became a problem because water in underground storage tanks “attached” itself to the fuel alcohol. The gasoline industry has eliminated water from storage tanks, thus overcoming this problem. Now the use of ethanol is advantageous because it will stop small amounts of water from collecting in an automobile’s fuel system.

Some critics say that ethanol contains less energy per unit volume than unblended gasoline. This is true—a 10% ethanol blend minimally reduces miles per gallon compared to pure gasoline. To overcome this deficiency, engines are being designed that take advantage of the high-octane benefits of ethanol while increasing fuel efficiency.

Fiction: Ethanol is made only from food crops such as corn

Fact: Food crops and nonfood crops play an important role in ethanol production

The amount of corn used each year to produce ethanol represents only about 5% to 7% of current annual production. After the corn is used to produce ethanol, the by-products of this process are a major source of animal feed.

As the ethanol industry continues to grow, the use of waste products and alternative crops will expand. Already, agricultural crops such as sorghum and food processing waste materials are used to produce ethanol. And new research is proving that biomass products such as pulpwood, rice straw, switchgrass, corn stover, and municipal solid wastes, will be used for ethanol feedstocks.

Fiction:The ethanol industry has been subsidized long enough

Fact: Government , in the form of tax incentives, is a positive investment in America’s energy needs

With gasoline prices at a historic low, ethanol production tax incentives are critical to allow for market penetration. At the federal level, tax incentives reduce the cost of ethanol blends by around 50 cents per gallon. Congress recently extended these incentives through the year 2007. Although in the past large corporations dominated the ethanol market, today more than 50 production facilities comprise corporate entities, farmer-owned cooperatives, and private ventures. These facilities account for more than 40,000 jobs and contribute more than $1 billion in household income.

According to the U.S. Department of Agriculture (USDA), if ethanol production reached 5 billion gallons annually, farm income would
increase $1 billion. In addition, as many as 108,000 jobs would be created, primarily in rural areas of the U.S.

Many state governments realize the potential for rural development embodied by the industry. For the top 10 corn growing states, USDA estimates a $464.8 mil-lion increase in tax receipts resulting from ethanol production. Presently, 16 states have their own incentives, ranging from direct subsidies to tax incentives.

Fiction: Ethanol does not benefit the environment

Fact:Ethanol significantly reduces engine emissions that endanger the environment

Ethanol consumption of 4 billion gallons annually would eliminate about 26 million metric tons of carbon dioxide emissions
Ethanol consumption of 4 billion gallons annually would eliminate about 26 million metric tons of carbon dioxide emissions

Since the beginning of the Industrial Age, atmospheric levels of carbon dioxide have increased 25%—and more than half of that increase has come during just the past 30 years. In the United States, about one-third of carbon dioxide emissions result directly from producing and consuming transportation fuels. Ethanol can provide a clean solution on two levels.

First, plants grown for ethanol production absorb carbon dioxide during growth, which reduces atmospheric levels of this greenhouse gas. If 4 billion gallons of ethanol were consumed annually, about 26 million metric tons of carbon dioxide emissions would be eliminated.

Second, ethanol reduces the carbon monoxide produced by combusting gasoline. As an oxygenate, ethanol stimulates more complete combustion, reducing the amount of carbon monoxide that is formed. And the reductions are significant. Tests at the National Center for Vehicle Emissions Control and Safety at Colorado State University document a 25% to 30% reduction in carbon monoxide emissions when automobiles burn a 10% blend of ethanol. EPA figures reveal similar results. In 1992, 21 new oxygenated fuel pro-gram areas—implemented nationwide—experienced a 95% reduction in carbon monoxide violations.

Fiction: Ethanol takes too much energy to produce

Fact: Ethanol is a that yields a positive energy balance

Whether it is produced from corn or other biomass feedstocks, the ethanol fuel cycle generates more energy than it consumes.

Compared with just 10 years ago, the efficiency of producing ethanol from corn has improved tremendously. Several factors contribute to this, including higher yielding corn varieties, efficient production and use of fertilizers and pesticides, and rapid advances in fuel conversion technologies.

A recent economic analysis that examined all phases of ethanol production concluded that ethanol made from corn outperformed gasoline by using less energy and producing fewer greenhouse gases. When other biomass feedstocks are considered—such as hybrid poplars and switchgrass, which require little energy to produce and harvest—the energy savings are even greater. Because biomass utilization requires fewer production inputs and yields energy by-products to help fuel ethanol production, ethanol made from biomass feedstocks yields much more energy. According to a fuel cycle evaluation conducted by the U.S. , the fuel cycle of ethanol produced from biomass feedstocks generates 6.8 Btu for every Btu of fossil energy consumed. The production of reformulated gasoline, which is used in many urban areas of the U.S., generates only 0.79 Btu of fuel energy for every Btu of fossil energy consumed.

Ethanol from biomass feedstocks yields much more energy than reformulated gasoline
Ethanol from biomass feedstocks yields much more energy than reformulated gasoline.


Once the facts are revealed, it becomes clear that using and producing ethanol for transportation is good for the United States’ economy, environment, and energy future.