METHANOL - AN ALTERNATIVE FUEL

GOAL:

To assist the students in understanding methanol as optional fuel and the technological effects of methanol as an alternative fuel.

OBJECTIVES:

The students will learn methanol's effects as an alternative fuel with respect to vehicle fuel economy, the environment, and technical changes in the vehicle.

LESSON/INFORMATION:

Several factors affect the use and selection of any fuel. Among the important ones are engine design, net energy per pound, net energy per gallon, and the sulphur content of alternative fuel properties.

SELECTED PROPERTIES OF PRESENTLY AVAILABLE FUELS.

Physical State	Gasoline Liquid	Liquified Petroleum Gas	Compressed Natural Gas	Methanol Liquid	Ethanol Liquid
Net Energy Content BTU/lb	18,700 19,100	19,800	21,300a	8,600	11,500
Octane Number Range (R + M) ÷ 2	87 - 93	104b	120b	99	100
Sulfur Content (W + %)	0.02 - 0.045	Negc	Negc	None	None

a - Pure Methane

b - Octane ratings above 100 are correlated with given concentration of tetraethyl lead in 150-octane

c - Natural sulfur content very low but measurable.
Source: Steering A New Course: Transportation, Energy, and the Environment, pages 75, 76.

Measuring a fuel's relative potential energy can easily be done by defining that fuel's Btu content. A Btu is defined as the amount of heat necessary to raise one (1) pound of water, one (1) degree Fahrenheit.

Present design internal combustion (IC) engines run on liquid fuels. Methanol requires few if any engine modifications to extract the maximum power from this fuel. As compared to gasoline, methanol lowers some tailpipe emissions, namely the sulphur based HC, CO, as well as NO_x. Methanol contains only half the energy per gallon of gasoline but has a very high octane rating. Increased compression ratios could yield 5 to 20 percent more power. Methanol can be produced from natural gas or from wood fiber. When made from natural gas, production costs are competitive; when made from wood fiber, production costs almost double. Production of methanol from coal and biomass, while possible in the laboratory, has not been economically demonstrated in a mass production process. When methanol is used as a gasoline additive, antiknock compound and fuel extender, it becomes economical with very positive results, especially from the emissions standpoint. It contains zero sulfur, thereby reducing tailpipe acids significantly. Of the six most popular alternative fuels presently available, methanol has the second lowest Btu/lb. net energy yield. As a result, fuel tanks will need to be enlarged for vehicles that run on pure methanol or driving range between refills will be reduced in half. See Figure 1 for graphic representation.

Figure 1.

Several manufacturers have begun developing "multi-fuel" engines that operate on many different fuels and in varying ratios. A key component in these multi-fueled vehicles is the on-board computer. Special sensors detect the type of fuel(s) present. The fuel injection, ignition and emissions control systems are automatically recalibrated to accommodate the current fuel(s).

Methanol is usually mixed with gasoline or ethanol in percentages ranging from five to eighty-five percent, with the lower percentage being more common. These blends extend gasoline fuel stock and reduce air pollution. "M85", a fuel composed of 85% methanol, is offered in some areas. Federal subsidies have brought production costs of this antiknock additive into close competition to the cost of producing other antiknock additives.

Initial changeover from gasoline to methanol could present some problems in the distribution system. Methanol is a detergent and has the ability to absorb water. Accumulated sediment and water sludge in storage tanks, pipelines, and in the vehicle fuel tanks could clog filters and create other operational problems. These systems must be scrubbed clean and prepared prior to the introduction of methanol fuels. Methanol concentration above ten percent is corrosive to some IC engine metals, rubber and plastic components, therefore manufacturing materials must be changed to accommodate this fuel. Specially formulated plastics, rubber, and extensive use of stainless steel are some manufacturing material solutions. Owner's manuals describe acceptable methanol concentration levels. Some manufacturers produce vehicles that perform satisfactorily at concentrations up to 85%. Fuel distributors label this fuel as "M85". Bold letters inform purchasers that the fuel contains methanol.

Preliminary DOE tests of optimized, M100 vehicles indicate that these produce significantly reduced tailpipe emissions. Only small performance and mpg penalties have been noted. Net operational costs, as compared to gasoline, seem to be equal.

ACTIVITY:

1. Determine what type of vehicles are available in your area which use gasoline or methanol or methanol blends. What are the recommended fuel percentage concentrations for each vehicle?

2. Determine if conversion systems are available in your area to run highly concentrated methanol.

3. For each vehicle or conversion system, determine each of the following:

a. extra cost for a new vehicle; cost (materials and labor) to install the system;

b. maintenance requirements, changes if any;

c. changed operational characteristics;

d. available (number) fueling stations in immediate area;

e. cost for fuel compared to pure, standard gasoline.

Summary: Write a short paragraph describing the advantages and disadvantages of using methanol as an alternative fuel.

METHANOL FUELED VEHICLES
Type of Vehicle		Type of System		Fuel System
Make, Model, etc.	Type of Fuel(s) possible	Factory Installed	Locally Installed	Cost (Materials and Labor)	Maintenance Changes	Operational Characteristics Changes	Available Fuel Station (Number Locally)	Cost of Fuel
				$
				$
				$
				$
				$
				$

COST PER GALLON (OR EQUIVALENT)

PURE METHANOL: $ _______________________________

METHANOL BLEND: $_______________________

STANDARD GASOLINE:$_________________________

INFORMATION CHECK

Directions: Indicate whether the following statements are true or false. If the statement is false, explain why it is false.

1.______ Methanol can economically be produced only from wood fiber.

2.______ Methanol yields the lowest Btu/lb.

3.______ When used as an antiknock compound, Methanol may be blended with gasoline and/or ethanol.

4.______ Non-standard fuel system materials need to be used in order for "M85" fuel to be used safely.

5.______ Unlike ethanol, methanol will not absorb water from gasoline.

TEACHERS NOTES:

Students MUST complete the guide "Alternative Fuels - What are They?" before they attempt this activity. A comparative understanding of alternative fuels is necessary before they can successfully proceed with this guide.

Methanol is a very misunderstood alternative fuel. Many technicians and pseudo-automotive buffs equate methanol with ethanol. They also relate "horror stories" of how alcohol based fuels have ruined automotive fuel systems. In truth, Methanol, in 5% or less concentrations, will not harm late model vehicles. The only possible harm could come from a gasoline-methanol mixture greater than 95:5. Methanol is highly corrosive to some standard automotive manufacturing materials in concentrations above 5%. Another possible side effect of changing over to methanol blended fuels is the possible detergent action on an older vehicle's fuel tank and lines. A system contaminated with fuel sludge and/or water will be cleaned by the methanol. In an extreme case, fuel filters could repeatedly clog until the system would be entirely cleansed of these contaminants. Some automotive manufacturers currently produce vehicles capable of safely burning M85 - an 85% methanol and 15% gasoline mixture.

ANSWERS TO INFORMATION CHECK:

1. False. Presently, the manufacturing of methanol from natural gas is the most economic process.

2. False. Methanol has slightly more energy than ethanol.

3. True. Presently, this is the most common use of methanol.

4. True. M85 is 85% methanol. In this higher concentration level, special materials need to be used in a vehicle's fuel system to prevent deterioration of these parts.

5. False. Like all alcohol, methanol will absorb water.

REFERENCES:

New Transportation Fuels, American Petroleum Institute, Washington, D.C.-1991. Special Issue Department, Public Affairs Group, _______.

The Automobile. Earth Day, 1990, Fact Sheet, Stanford, CA. 1990.

Gordon, Deborah, Steering A New Course: Transportation, Energy, and the Environment. A Report by the Union of Concerned Scientists, Cambridge, MA 1991.

Motor - Vehicle Fuel Efficiency and Global Warming. Union of Concerned Scientists Briefing Paper: Cambridge, MA. 1991.

Duffy, James E., editor and Howard Bud Smith. Auto Fuel Systems. Goodheart Wilcox Co., South Holland, Illinois. 1987.

Bata, Reda M. Ethanol and Methanol Blends with Gasoline; an Experimental Approach to Engine Performance and Emission. Unpublished Dissertation.

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