A Live Green, Live Smart™ Briefing 
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America - and the world - is coming to terms with the difficult premise that petroleum fuels are neither environmentally safe nor infinite. In seeking alternatives, many groups are hitching their wagons to renewable fuels, which hold a twofold promise: to be an infinite supply of fuel for America and the world, and to reduce the presence of carbon dioxide in the atmosphere. Increasingly, farmers, lobbyists, and the government look to ethanol, a fuel made from plants, as a substitute for gasoline. Whether ethanol and other agricultural biofuels are endlessly renewable, and whether they eliminate as much greenhouse gas as promised, are still open for debate.
Ethanol is an alcohol, distilled from fermented plant sugars. It is a sweet-smelling, colorless, slightly toxic liquid, before being made into fuel it's the same alcohol in beverages and medicinal alcohol. Like these alcohols, its source is grain and other plant matter. In the past decade ethanol production has become commercially viable and liquid ethanol now provides fuel equal to 5% of the gasoline used in the US. American fuel ethanol is largely - 97% - produced from ordinary field varieties of corn already being grown for animal and human consumption.
The production of ethanol from corn is a three-step process. First, corn starch - long chains of sugar molecules - is extracted from the plant. Then, that starch is broken up into sugar. Finally, the sugar is distilled - chemically altered by heat and enzymes - into ethanol.
Ethanol as a fuel has many attractive characteristics. It burns slower, cleaner and more completely than gasoline, creating less smog and greenhouse gas. In countries with abundant agricultural land ethanol offers some independence from the geo-politics and geology of oil supplies. Ethanol biodegrades quicker than gasoline and is less toxic, both for the planet and for humans. Even engines themselves seem to like a difference between gasoline and ethanol -- the higher octane of the ethanol makes rough running or engine knock less likely than with gasoline fuel.
Fuel ethanol is most readily available as a gasoline additive; 46 percent of the nation's fuel supply is E10, also called gasohol, a blend that is 90 percent gas and 10 percent ethanol. A gasohol blend is desirable because it blends the power of gasoline with the environmental and engine health benefits of ethanol. Additionally, the E10 blend helps make a dent, albeit very small, in our need for oil.
Ethanol supporters would like to see more cars run with E10, and would eventually like to see cars run on a fuel blend of 85 percent ethanol and 15 percent gasoline, E85. The expanding ethanol industry has made E85 its premier fuel and the focus of a nationwide marketing push that has found some of its strongest advocates in the legislatures and governors' offices of large agricultural states, where local mandates for the sale of E85 are gaining ground. In response, domestic carmakers have increased production on flexible fuel or "flex-fuel" vehicles, which can run on either E85 or gasoline.
The American ethanol industry has a long history, longer than many of us imagine. The original Ford Model T, built in 1908, could be modified to run on gasoline or pure ethanol. Henry Ford called it the "fuel of the future." Since then, however, the gasoline industry flourished while the ethanol fuel industry faltered, at least until the 1970s when the furor over leaded gas and the Arab oil embargo led many to reconsider the benefits of ethanol as a fuel that could burn clean, and that could reduce the country's dependence on foreign petroleum. When leaded gasoline was banned, ethanol, along with MTBE, became the additive of choice to replace lead in gasoline as an octane booster. Today MTBE is falling out of favor because of its toxic mercury content, and ethanol as E10 is poised to take over the additive market, bolstered by federal tax exemptions to companies that blend their gasoline with ethanol.
The industry infrastructure has grown accordingly. In 1980 ethanol production was 175 million gallons. In 2005 ethanol production was at 4 billion gallons, and nearly 5 billion gallons in 2006. The industry-estimated potential for 2007 is over 6 billion gallons, using nearly 20 percent of America's corn crop. Currently more than 110 ethanol plants operate in the US, with at least 80 more under construction.
Research by the US Department of Energy and the Argonne National Laboratory shows that E10 reduces tailpipe greenhouse emissions up to 12 percent. E85, depending on its source, whether it be corn or cellulose, can reduce greenhouse gas emissions between 18 and 28 percent. These percentages reflect two factors: that corn, while it grows, takes carbon dioxide from the air; and that ethanol burnt in the engine creates less carbon dioxide than gasoline.
The production of ethanol yields several byproducts, including livestock-grade food.
Ethanol Concerns
The group of vocal ethanol critics is growing each day. The concerns over ethanol production begin at the farm.
Corn farms, like any farms, displace natural habitat and replace it with farmland, and also contribute heavily to water shortages, water pollution, and soil pollution. This is already a problem in America, and with more acres being planted to harvest corn for ethanol, farm-related habitat destruction will only increase. The USDA estimates that in 2007 90.5 million acres of corn will be planted, a 15 percent increase over 2006 that is largely a response to the increased demand for ethanol stock.
Corn is a staple of the American and world diet, and farms in America grow 40 percent of the world's corn. But America has only so much space for farms; 60 percent of the nation's land is already used for either crops or livestock. To achieve the President's stated goal of replacing 20 percent of the country's gasoline with alternative fuels, we would need, at the present rate of consumption, 35 billion gallons of alternative fuel - ethanol - a year. That equals about 320 million tons of corn. The US already produces 280 million tons of corn a year, almost all of it for food for humans and livestock. A quick look at the numbers seems to show that the President's goal is improbable, if not impossible using current methods. Things could change with the advent of cellulosic ethanol and biodiesel, but like electric cars, these fuel possibilities always seem to lie in the future, never in the present.
Put simply, many believe we just don't have the farmland available to grow all the corn we need for food and for ethanol. One wonders how we will be able to decide between the two.
Because the ethanol market is strictly tied to corn crop availability, as the demand for ethanol increases, so does the price of corn. At the time of writing, the price of corn is hovering around $4 a barrel, a doubling of price from a few years ago. Widespread use of grain for high-demand fuel may eventually price food beyond the reach of the world's poorest people.
Corn farming does damage to the topsoil. Topsoil is the fertile, nutrient rich part of the soil into which plants dig their roots, and on some Iowa farms the topsoil has gone from a depth of 18 inches to 10 inches. The destruction of topsoil is what turns usable land into desert. Production of corn year after year deprives the soil nitrogen, a natural fertilizer, and bacteria that recycle plant waste into plant food. Corn is a row crop. The spaces between corn rows allow soil on the surface to be blown away at a rate 50 times higher than a sod crop like wheat or alfalfa. Grow too much corn and soon we may not be able to grow any at all.
Is Ethanol a Renewable Fuel?
While corn itself is a renewable resource, growing by photosynthesis which uses sunlight and carbon dioxide as fuel, the infrastructure needed to produce and process corn for ethanol manufacture is still dependent on fossil fuels. Farm machinery used to plant, cultivate, and harvest corn currently burn conventional gas and diesel; factories that make the pesticides and fertilizers for optimal crop yields also use fossil fuels in their production processes. The plants distilling ethanol are also dependent on fossil fuels, coal and natural gas primarily, to provide the heat and power needed to stimulate the chemical changes required.
And E85, the fuel blend ethanol supporters wish to see in America's gas tanks, is 15 percent gasoline. All along the way, from farm to factory to fuel tank, ethanol continues to be least partly dependent on fossil fuel, that dwindling resource. To call ethanol a renewable fuel, then, is partly true.
Cellulosic ethanol may prove able to mitigate many of these fossil fuel needs; producers predict that cellulosic biomass (grasses, for example) grows quicker, easier, and with fewer chemicals than corn, and is more easily rendered into ethanol with less fuel input. Additionally, cellulosic ethanol plants can repair the corn-caused nitrogen deficiencies in topsoil and prevent erosion that corn cropping exacerbates because of the plowing and cultivating that it requires. At this writing, the cellulosic ethanol industry is still in its infancy and cannot yet provide real-world data to support predictions of its success.
Is It Worth It?
The question then becomes, is the energy we get out of ethanol worth the fossil fuel energy we use to make it and the artificial chemicals and water we use to grow the material for its production? The most recent Department of Energy study shows that there is a positive energy gain in producing ethanol. This means that for every one million units of fossil fuel energy used to make ethanol, 1.22 million units of ethanol energy are produced. In comparison, the making of gasoline results in a net energy loss; for every million units of fossil fuel (coal and natural gas) used to produce gasoline, only 770 thousand units of gasoline energy are produced.
Most other studies support the DOE's research, but a vocal minority have concluded that even these modestly positive energy gains are wrong, and that there is actually a net energy loss in the creation of ethanol.
Assuming the DOE's research is correct, while there is a surplus of energy from the creation of ethanol, this energy is less concentrated than it is in gasoline; when looked at by volume, ethanol contains less energy per gallon than gasoline - about 34 percent less. For you, the driver, this transfers into a drop in fuel economy and more frequent fill-ups; to drive a mile, one would, in theory, need 34 percent more ethanol than gasoline. Ethanol's mixture with gasoline in E85 makes this decrease in fuel economy less dramatic. In any case, practice, different engines consume ethanol with different efficiencies.
Ethanol's Availability
Ethanol's key selling point is its potential to reduce our dependence on foreign oil. As previously noted, all aspects of ethanol production at the present time require fossil fuel input, whether it be coal, natural gas, gasoline, or diesel. All that aside, could ethanol have the ability to make a serious dent in our transportation-related gasoline usage?
Well, with current technology and at current rates of use, the American transportation sector blows through over 140 billion gallons of oil a year. Ethanol production, while climbing every year, is at about 7 billion gallons, or five percent of the total - this from nearly one fifth of America's corn crop.
As E10, ethanol can already be found as an additive in 46 percent of the nation's gas tanks. The distribution level of E85, the ethanol industry's premier fuel, is much smaller. Out of 160,000 total nationwide, only 1,200 filling stations carry E85. That's 0.75 percent of gas stations. Furthermore, most of these stations are concentrated in the Midwest. So while carmakers are producing more and more flex fuel vehicles able to run on E85, a number of these cars will not actually see an E85 pump for years.
One reason for this slow expansion is the fact of ethanol's propensity to attract water and other contaminants. Because of this characteristic, it cannot be transported via the existing pipeline system, and must be trucked by tanker to depots and retailers - and, for now, those tanker trucks burn carbon fuels.
As we have seen, the ethanol industry is growing, but at the present is not even close to being the key to energy independence that its proponents claim it will be. One fifth of America's corn crop produces only around five percent of America's fuel needs, and the kind of ethanol fuel supporters want us to buy, E85, is only available in 0.75 percent of the country's gas stations.
Can we ever make enough ethanol to stop using oil? We can't be sure - but it is possible that ethanol will be a transitional fuel that provides a little slack in oil demand during a conversion to emission-free renewable fueled engines. And time is of the essence.
Written for Live Green, Live Smart by Jack Hays (jack@jacksonhays.com)