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Driving Without Gas - Chapter 2
Gasohol and the Revival of Grain Alcohol (Ethanol)
Gasohol is an idea that has been smoldering for years in the nation’s corn-belt, and now it is sweeping out to all corners of the country – a bit like an out-of-control brush fire. More than 2,000 service stations sell Gasohol. In the farming regions of the Midwest, automobile bumper stickers boost this newly named fuel that is derived, in part, from corn: SUPPORT AMERICAN HOME-GROWN FUEL, says one; PUT AMERICA BACK IN THE DRIVER S SEAT: USE GASOHOL and MY CORNFIELD IS YOUR OILFIELD are others.
For many, Gasohol is nothing more than an old idea whose time has come. The term Gasohol is defined as a mix of 90 percent unleaded gasoline and 10 percent (200 proof) ethyl alcohol (ethanol). Corn is the most common fermentation feedstock for the manufacture of ethanol used in Gasohol. During World War II, alcohol fuel mixes were used in Europe to help conserve petroleum. Even earlier, in the 1930s, Nebraskans pressed for legislation encouraging alcohol fuel production. At the urging of Gov. Charles Bryan, the state legislature passed a bill that allowed farmers tax rebates on alcohol blends. Iowa and other grain-raising states passed similar legislation in the 1930s and 1940s.
When "cheap" petroleum fuel became widely available after World War II, interest in alcohol fuels faded. But now, hundreds of thousands of gallons of grain alcohol are produced for fuel every day. One of the nation’s largest producers, the Archer Daniels Midland Corporation of Decatur, Illinois, ships alcohol to more than 40 states. According to the Department of Energy, ethanol production for fuel use is expected to exceed 500 million gallons by 1985. In the meantime, Gasohol, the best known alcohol-gasoline fuel, is gaining ever-wider acceptance as more and more motorists become frustrated and fed up with high-priced, im-ported petroleum products (Figure 2-1).
Figure 2-1. Gasohol sales increased dramatically in the state of Iowa, as shoran in this graph adapted from data provided by the Iowa Development Commission. One key factor was the implementation in January 1979 of a federal tax exemption of 4 cents a gallon.
HOW DOES GASOHOL PERFORM?
Even the big three automakers are taking a close (but not overly enthusiastic) look at Gasohol. General Motors, Ford and Chrysler say the use of Gasohol containing up to 10 percent ethanol does not invalidate warranties on their vehicles. Even though some manufacturers are developing and producing cars to operate on pure, 100 percent ethanol, most suggest that motorists contact their dealers before putting straight alcohol in their tanks. The implication is that cars so powered would not be fully war-ranted.
Mileage test results for cars using Gasohol are not conclusive. For example, the Illinois Bell telephone company compared 15 vehicles using Gasohol with regular gasoline. The results: "The vehicles using Gasohol averaged 4.43 percent better mileage. Our monthly maintenance review of the vehicles also indicated some savings in engine maintenance with the cleaner-burning Gasohol," said the company’s manager for automotive services. "We also found that Gasohol virtually eliminated gas line freezing problems during the winter months."
Other studies have said cars powered by Gasohol attain 3 to 5 percent better mileage. One well-known study, The Nebraska Two-Million-Mile Gasohol Road Test Program, reported that Gasohol-fueled cars got an average of 5 percent more miles per gallon than cars using unleaded gasoline. And the Land O’Lakes corporation of Fort Dodge, Iowa, reported that different motorists’ driving habits affect mileage, but test results with fleets of up to 100 cars showed a 3 to 5 percent increase.
General Motors, though, which has experimented with ethanol seriously for several years, has said, "For the average vehicle, fuel economy will be lower with Gasohol than with gasoline because of Gasohol’s reduced heating value... for most vehicles, the fuel economy penalty (emphasis added) for Gasohol will be in the range of 0 to 3 percent."
Some Detroit engineers contend that ethanol contains only two-thirds of the energy measured in Btu of the gasoline it replaces. What they may sometimes fail to mention is that the two-thirds represents 60 percent of
Motorists in most of the states can find a service station providing customers with Gasohol, a blend of unleaded gas and alcohol. (Iowa Development Commission)
the ethanol used in Gasohol, and the need for energy in the form of gasoline is reduced by that amount. Also, as pointed out by the Conference Board, an authoritative business journal, ethanol combusts more efficiently than gasoline. About a third of the weight of an ethanol molecule is oxygen, and that makes for better burning and peppier engines, especially in older cars. (James Krohe, Jr., "Gasohol: It Has Turned Skeptics Into Believers. Well, Some of Them," Conference Board, October 1979.)
Most alcohol fuel enthusiasts and experts agree on at least one point: Gasohol has an average octane rating that is three or four points higher than plain unleaded gasoline. This higher rating means that engine knock and pinging are eliminated in many cars. But Joseph Colucci, fuels and lubricants department chief for GM, contends that the higher octane of Gasohol will not improve fuel economy because most car engines are not designed for it. In the future, Colucci says, if Gasohol use becomes wide-spread, engine compression ratios might be increased to take advantage of the higher octane quality of Gasohol. More likely, the oil companies might utilize the ethanol as an octane-boosting agent. This would permit them to decrease the severity of their gasoline refining operations, and thus decrease refinery energy expenditures.
WHAT IS OCTANE NUMBER?
Early in the development of the modern internal combustion engine, it be-came necessary for engineers to know the quality of liquid fuels and to design engines that could best use their energies. Many liquids and gases were tested in a one-cylinder laboratory engine that had a variable stroke, so that piston travel and hence compression ratio could be changed at will.
A liquid called heptane would cause knocking at any compression ratio, while iso-octane, another hydrocarbon, would not knock at all. When an unknown gasoline was to be tested, the engine’s compression ratio (C.R.) was increased, while running on this fuel, until it began to knock. Then the engine, with the same C.R. setting, was run on heptane, and octane was added by a mixing valve until the knocking faded away. If this occurred when the mixture was 70 percent octane, the unknown fuel could be labeled 70 octane.
FIGURE 2-2. COMPARISON OF IMPORTANT FUEL PROPERTIES
Properties Typical Gasoline Ethanol Gasohol
(Wt. % )
0 35 3.7 Chemically correct air-fuel ratio 14.5 9 13.9 Energy content (Btu/gal.) 114,00 75,000 110,000 Vapor pressure (lbs./in.2) 10.0 2.2 10.7 Octane quality* 87 98 90
*Average of research and motor octane numbers. Source: General Motors Research Laboratories.
Actually, increasing compression ratios, by "shaving" cylinder heads, is nothing new. Just before World War II, I acquired a used English sports car. Its engine had been "souped up" by shaving off the cylinder block to raise the compression ratio to more than 8:1, giving the engine more compression than most cars of that time. Although I used the highest octane premium gas available, the engine knocked at the slightest acceleration.
At a gathering of racing enthusiasts, an English owner of a similar car advised me to give it alcohol. Thereafter, with about 10 percent methanol, an alcohol fuel with an octane number estimated to be over 100 (Pure methanol has an octane of 106). I had no more knocking and ventured forth on an oval track to race. My car reached speeds of 85 mph regularly, and a rough computation indicated that the little engine, no larger than the one in a Model T, produced six times the original horsepower when in trim and when operating on the alcohol blend.
Even if the notion of high speed in an automobile is in disrepute, a small engine with a high compression ratio is much more efficient in weight, cost and fuel consumption than a large, sluggish engine. Without high-octane fuel, the modern car could not have evolved. The British, with an oppressive tax on cars with engines of large dimensions, are to be thanked for evolving the light, high-compression ratio, sports-car engine.
Tetraethyl Lead. Before the advent of Gasohol, tetraethyl lead was the standard additive for increasing octane number. It was such a good booster that gas of 50 octane could be raised to 60 by adding 1 cubic centimeter of lead per gallon; 2 cc would push it to 68, and 3 cc achieved a maximum of 72. Most of today’s refineries were designed to produce the largest possible amount of 60- to 70-octane gas. This was adequate, with lead additive, for the newer cars, up to the beginning of the war on air pollution.
The war on air pollution was, in part, a war against lead. Lead residues accumulate along roadsides, and they represent a serious health concern. There have been frightening studies in urban areas of Massachusetts of lead concentrations in children's teeth. Small amounts of body lead are related to learning disabilities and serious childhood diseases.
Catalytic converters help break down and reduce harmful exhaust emissions. But, unfortunately, catalytic converters cannot tolerate lead. And the refineries are still struggling to improve their processes to raise the natural octane number. They have tried the additive MMT (methyl-cyclopentadienyl manganese tricarbonyl), which also seems to have a bad effect on catalytic converters. It was phased out of production in September 1978.
Tetraethyl lead is to be banned as a fuel additive, on a lingering schedule that began in January 1978. Under these restrictions, there’s insufficient lead to provide enough octane boost for the new high-performance cars. Therefore, the three largest oil retailers have pulled some old tricks out of the racing drivers’ medicine kit to extend octane without lead. They’ve added up to (and in some cases more than) 15 percent benzine to certain premium unleaded fuels. Although benzine is an excellent octane booster, it is also a carcinogen. Amoco and Arco premium fuels are said to be fortified with 5 to 7 percent tertiary butanol – a fine, higher alcohol produced from petroleum.
Thus alcohol is the only practical fuel additive that gives a genuine octane boost without increasing pollution (it lowers it, in fact). Also, alcohol is not carcinogenic, not imported, and not harmful to catalytic converters.
Separation problems. When small amounts of water accumulate in a fuel tank containing an alcohol-gasoline blend, the two components tend to stratify as the temperature drops. The alcohol settles at the bottom of the tank. When it is pumped up for a cold start in the morning, the alcohol fails to vaporize in the carburetor, and it is necessary to heat the inlet manifold, by an external or internal electric heater.
Another option is a primer that provides a brief starting injection of propane gas, ether or volatile gasoline. Such a primer is expected to be a routine accessory on the future cars designed to burn 100 percent alcohol, but it should not be necessary for the transition period ahead, when blended fuels and unmodified engines must be coordinated for the North American climate.
Nebraska test. In the Nebraska Two-Million-Mile Gasohol Road Test Program there was little dissatisfaction with car performance. Drivers said they experienced no hard starting or stumbling of the engines. Furthermore, they said, the Gasohol-fueled cars appeared to have better pick-up. No vapor lock was reported, and overall driver satisfaction with car performance was high.
One of the finest things about burning alcohol in an automobile engine is that the exhaust emissions are generally far cleaner than from regular unleaded or leaded gasolines. Almost all automotive experts agree that Gasohol-powered cars emit less carbon monoxide – some studies say as much as 25 percent less. But, Gasohol may either increase or decrease hydrocarbon emissions and nitrogen oxides emissions, depending on how the engine is calibrated initially. The Nebraska test showed a total reduction of all emissions, but the total amount for Gasohol was only slightly less than that for unleaded gasoline. (See Figure 2-3.)
FIGURE 2-3. SUMMARY OF ERDA EMISSIONS AND FUEL CONSUMPTION TESTS AT 75º F. (24º C.)
Engine Parts and Other Considerations
GM and many others that have experimented with Gasohol have not found that using the new alcohol-gasoline blend causes any material or component failures in automobiles. While GM cautions that more experience with the fuel is needed before its long-range impact on cars and their parts can be determined, the big three automakers are not invalidating their car warranties.
From my experience with alcohol fuels, and from the reports of tests by others, it is safe to conclude that there are a few results that can be expected from using an alcohol blend in a car;
l. Ethyl alcohol or ethanol tends to dissolve gook and sometimes frees rust in fuel lines and in the fuel tank. The fuel system is cleaner after a tankful or two, but the fuel filters often must be either cleaned or replaced.
2. As shown in the Nebraska test, Gasohol is even safer than pure alcohol, which may damage certain parts. Gasohol and unleaded gasoline produced no difference in engine cylinder wear. There were no more carbon deposits or wear to spark plugs, valves or valve seats and no premature failure of any engine parts or fuel-line components.
ETHANOL: RUNNING CARS ON "STRAIGHT" ALCOHOL
In Brazil, where there are acres and acres of sugar cane, an ideal agricultural product for making alcohol, there is also a national commitment to develop and manufacture automobiles that operate on nothing else. By 19I32, Brazil expects to produce or modify nearly 1.1 million cars to operate on 100 percent alcohol. Seven hundred test vehicles already operate on pure alcohol and many more are using alcohol blends. Ultimately, Brazil plans to manufacture only cars that operate on pure alcohol.
This is a major international program, involving American, Italian, German, Swedish, and Japanese automakers. Ultimately, the program will help to free the Latin American country from its dependence upon petroleum. It also will be a major boost to Brazil’s agricultural industry.
Brazil is leading the world in the production of alcohol-fueled cars and Americans can operate their own cars with straight alcohol as well. In fact, ethyl alcohol, or ethanol, with a proof of only 160 (80 percent alcohol; 20 percent water) will work in simply modified cars. More and more car enthusiasts and experts are experimenting with ethanol – in cars, tractors and even power boats. To operate a combustion engine on ethanol, a few modifications are necessary.
It is possible to operate many cars on the road today with pure ethanol if they are equipped with properly adjusted carburetors, and if they are able to vaporize enough fuel to get the car started at temperatures below 50º F. Also, ethanol is more corrosive than gasoline to some fuel filters, lines and tanks, meaning that these items might have to be replaced or modified. But these problems are far from insurmountable. Carburetors can be modified; durable parts can be substituted for those subject to corrosion.
Carburetor and fuel pump. Ethanol of 160 proof or better can be used in most ordinary cars if the flow of fuel to the engine is increased. Fuel must be increased because the heat values for ethanol are lower than those for gasoline. Hence, the carburetor fuel jets must be enlarged, usually by about 40 percent. The fuel pump, now called upon to deliver twice as much volume as before, also must be augmented.
Starting device. Another desirable addition, and one that is a necessity if you live in the northern United States, is some form of device for starting in cold weather. This device can be either a block heater, or a propane gas cylinder, solenoid valve and a pressure-reducing valve. The propane system is designed to inject the flammable gas into the air cleaner when you turn on the car starter switch. While propane gas will remain in the vapor state until it reaches the cylinder, alcohol becomes more difficult to vaporize as the thermometer drops below 50º F.
Preheater. Even when vaporized in the carburetor, alcohol may condense on the cold walls of the intake manifold. Compared with gasoline, alcohol produces larger droplets and rapid coagulation that makes proper distribution of the fuel-air mixture to each cylinder more difficult. This is the reason for the gas starter, and for the addition of air preheating. The latter is accomplished by passing the incoming air over part of the exhaust system. Light sheet metal scoops are the usual solution, while flexible metal ducting, of a diameter somewhat greater than that of the carburetor inlet, may also be run against a section of exhaust pipe.
The best place for an air intake heater is usually along the short but hot section of the exhaust manifold. Most air cleaner intakes can be rotated, and an inspection of your exhaust system will indicate that a three-sided channel of sheet metal or a piece of flexible metallic duct, leading air backwards from the radiator, over the exhaust pipe, can be connected to the air cleaner horn (intake). These connections, and the fit of the scoop over the exhaust pipe, need not be perfect fits, up to the cleaner. The tuning of the carburetor, with and without the air cleaner, will be different.
Another way to modify an ethanol-powered engine to improve its performance is to raise the engine’s compression ratio, and adjust the timing. Raising the compression ratio, while not essential, is one of the best changes to make to achieve improved performance and fuel economy. This job is best done by an experienced machinist or auto mechanic.
ECONOMIC AND SOCIAL ISSUES
The State of New York studied a fleet of cars powered by Gasohol and then issued an 18-page report. Included was what the authors of the report called a "provocative review of the whole Gasohol issue." The word "provocative" hinted at the tone of the review and its likely conclusions; the opening quote was a pure giveaway:
"One of the great tragedies of life is the murder of a beautiful theory
by a gang of brutal facts." Benjamin Franklin
If you’ve read this far, you probably need no further coaching to guess what this "review" established about the notion of fueling cars with corn power. In short, the report by the state’s agriculture department, concluded that Gasohol produced from feed products would be nothing less than a "disastrous food and farm policy."
But for every New York state agriculture department, there are other departments or reports with the opposite view – that making alcohol fuel from corn is a sensible, timely idea. At the same time, dozens, hundreds, perhaps thousands of scientists, researchers, experimenters, sociologists and even politicians are trying to determine just exactly what the "brutal facts" are about alcohol fuels. Opinions are sharply divided. Definitive statements are scarce or outdated. But there are a few persons willing to argue on both sides of the many economic, social and political issues that swirl about the words Gasohol and ethanol (ethyl alcohol).
Alcohol Production Costs
There are at least two ways to examine the costs associated with ethanol – from a production viewpoint, and from the viewpoint of the consumer. What does he pay for an ethanol blend such as Gasohol when he drives up to the gas pump? Many researchers and fuel experts agree that the energy consumed in the production of a gallon of ethanol is as great as the energy derived from that gallon. But, others ask, isn’t that true of conventional fuels as well? And just exactly what is included in production costs?
Again, few agree on what should be included in a fair assessment of the costs of producing ethanol. But, however you look at the costs, no matter what you include in the equation, it’s always true that whenever we convert from one form of energy to another – from corn to alcohol, or from coal to electricity – there is an energy loss. In this kind of conversion, ethanol doesn’t do too badly. For example, compare corn-to-ethanol to another conversion we have tolerated for years – coal-to-electricity.
*If the Btu losses in mining coal were included, it could be shown that generating electricity with coal is a totally useless operation. If the value of human lives lost could be included in mining costs, the situation would be far worse.
Other studies suggest that ethanol can be produced even more efficiently with new and improved technology or with other feedstocks besides corn. For example, one study conducted by Battelle Columbus Laboratories for the American Petroleum Institute, the oil industry’s major organization, determined that "ethanol from sugar cane" is a "net energy producer." Methanol, if produced with processes now under consideration, could also be a net energy producer. (See Figure 2-4.) The Battelle study considered all energy costs associated with production – fuel to grow feedstocks, fuel to make fertilizer, and fuel to run the alcohol production process.
But Battelle’s conclusions about sugar cane differ slightly from those of a research team at Louisiana State University’s Coastal Ecology Laboratory. The LSU researchers determined that about 2.7 acres of sugar cane could produce alcohol worth about 18.4 million calories of energy. This, they calculated, would be about 900 calories less than the energy required to produce the alcohol. This appears to be a small energy loss, but other studies have produced even more unfavorable equations for ethanol.
One way to cut ethanol energy-production costs would be to use crop residues such as corn stalks as a fuel for the ethyl alcohol distillation. But Gasohol detractors are not at all pleased by this suggestion, either. They point out that massive use of agricultural wastes as a fuel would hasten soil depletion. And many are horrified at the thought of using anything like corn to run automobiles. Here’s a typical analysis from an opponent of alcohol fuels from corn:
United States gasoline consumption is 100 to 110 billion gallons yearly. A 10-billion-gallon Gasohol program would use 1 billion gallons of alcohol. To produce this amount of alcohol from corn would use over 50 percent of present corn reserves and over 280 percent of the corn which farmers hold under the federal loan program. This program level would only displace 0.8 per-cent of our current imported crude oil use. To displace 8. 2 percent of our cur-rent crude oil imports would take 57 percent of all current corn acreage.*
*Report on the Testing of Alcohol/Gasoline Fuel Blends in Conventional Vehicle Fleets in New York State, Office of General Services, Division of Interagency Transportation Services, New York State, March 1980.
Of course, an immediate transition to such a massive corn-alcohol program is unlikely, if not impossible. But there are many thoughtful people who question the wisdom of shifting the purpose of corn from food to fuel. One fact they may sometimes overlook is that the government in 1978 alone paid more than $1.6 billion to farmers to compensate them for not planting crops.
The Department of Energy predicts that the feedstocks for alcohol fuels in the 1980s will probably be wastes from agricultural distressed products and by-products. Cellulose materials not useful as food, and coal and peat could be processed in the future to produce ethanol and methanol, respectively. *
* The Report of the Alcohol Fuels Policy Review, U.S. Department of Energy, Washington, D C., June 1979. See Appendix B for a discussion of this report.
In the meantime, researchers are looking for ways to assure a bright future for ethanol by reducing the costs of production. For example, Michael Ladisch and Karen Dyck of the Laboratory for Renewable Resource Engineering at Purdue University announced a method of reducing the major energy requirement of distillation (50 to 80 percent of total manufacturing heat) of ethanol to the high proof needed for Gasohol. Instead of lengthy redistillation of the "beer," a mixture of water and alcohol vapors, the Purdue team passes these over cornstarch at a moderate 90 degrees centigrade. The water is absorbed by the starch, while the alcohol is rejected and condensed. The wet starch is then used, without drying, in the feedstock. The combustion energy of the product can be 10 times greater than the energy needed to dehydrate it.
The Cost to Motorists
To the surprise and bewilderment of some oil industry executives, more and more motorists are buying Gasohol – even though it often costs at least a few cents more than regular or unleaded gasoline. Why? Because Americans prefer a domestically produced fuel that they believe will help reduce foreign imports, will keep gasoline costs down, and will do the least damage to the land. Presumably, they see coal extraction as more damaging. These were among the findings of a Louis Harris poll of 7,010 Americans 18 years of age or older.**
**Louis Harris and Associates Survey conducted between October 19 and November 21, 1979.
In an earlier study in Iowa, consumers said they liked Gasohol because they believed it extended oil supplies, improved automobile performance, and helped the corn market. Only 21 out of 514 users of Gasohol said they encountered problems. "Rougher-running engines and plugged fuel filters, which are not unusual problems in initial tankfuls of Gasohol, were experienced by 10 of 21 users."1
1"Gasohol Acceptance in Established Markets," Iowa Development Commission, April 19, 1979
One reason Gasohol remains competitive is that the price of gasoline is increasing and Gasohol is getting help from Uncle Sam in the meantime. Ethanol costs nearly twice as much as unleaded gasoline at the wholesale level. But by the time the ethanol-gasoline blend reaches the gas pump, it costs only a few cents more than the traditional fuel. The government exempts the sale of Gasohol from the four-cent-a-gallon federal gasoline tax. And several states have tax reductions in effect for alcohol fuels.
There may be political, as well as economic reasons for motorists to fill up with Gasohol. It doesn’t seem to be a coincidence that much of the support for Gasohol comes from the corn belt and other southern states where self-sufficiency and independence from foreign petroleum are on the minds of many. This sentiment was captured quickly by a new firm in Buena Vista, Georgia, marketing a portable alcohol-fuel distillation unit. The unit was called, in large letters painted across its side, THE OPEC KILLER.
Gasohol, from an economic point of view, is at the crossroads. We are waiting and the price of a barrel of oil goes up a few dollars every month, and the price of gasoline at the pump goes up a dime at regular intervals. We see farm surplus produce piled in mountains, and find it hard to believe that we would starve if motor fuel were to become a farm crop.
The first and last objection to alcohol fuel – its price – is almost certain to vanish in the all-too-near future.
Copyright 1980 by Garden Way, Inc.
This material provided under "Fair Use" guidelines.
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