Fuel Efficiency

Fuel efficiency means to do more with less. Efficiency is achieved by improving technology, so that less energy is consumed while getting the same or better results. A new automobile that gets better gas mileage without reducing power or performance is an example of how advances in technology can save energy by increasing efficiency, rather than relying on conservation (reduced performance or restricted use) as the only way to save energy.

Some people like to fool themselves by thinking that a larger gas tank is the same as higher gas mileage. But if gasoline shortages occur, caused by either a natural or deliberate disaster—or another oil embargo, fuel prices will spike again, everyone will be subjected to gas rationing, and a larger fuel tank will not help.

When the world economy recovers from the current economic recession, and if world oil supply cannot meet growing demand, experts predict the price of gasoline will quickly return to $4 per gallon and could soar to $6. This prediction does not consider an actual oil supply interruption — this prediction assumes global oil production remains steady, but demand continues to push supply to its limits — a scenario which makes the possibility of a supply interruption very real.

During the Arab oil embargo of 1973-74 and the Iranian Revolution of 1979-80, Americans were subjected to gasoline rationing and long gas lines at the gas station. As a result, gas guzzling cars and trucks were called “Gas Hogs” and their value dropped to nearly zero.

Today, people who own SUV’s and pickup trucks are hurting — $4 gasoline caused the value of their SUV’s and trucks to drop faster than the value of their homes. The gas guzzling cars and trucks are not selling — GM and Ford have cut production of large vehicles, and many autoworkers whose jobs depended on SUV and Truck sales are now unemployed.

And, the amazing thing is that all of this has occurred without any real shortage or interruption in the supply of oil. If a real shortage occurred, gas prices would spike beyond $6 and reach $10-$15 per gallon overnight. Americans would be faced once again with gasoline rationing.

If gasoline rationing forces drivers to wait two hours or more in long gas lines before taking their turn at the pump, drivers will add the value of their time to the price they pay for gas. Fuel efficiency is not only about the price of gas; it is also about how far you can drive on a limited amount of gas.

Fuel efficient cars and trucks will help protect families from the rising cost of gasoline and will also ease the pain of any future fuel shortage or gas rationing.

A typical gasoline powered automobile is only about 25% efficient. In other words, out of the 100% thermal energy potential of a gallon of gasoline, only about 25% of the energy is converted to real mechanical work that turns the wheels of the car — the other 75% is lost in the form of wasted heat and friction.

Corporate Average Fuel Efficiency (CAFE)

The United States Congress enacted legislation in 1975 requiring the doubling of fuel efficiency for new cars. Today that Legislation is known as the Corporate Average Fuel Efficiency (CAFE) standards. The CAFE standards were increased again in the 2007 Energy Bill.

The CAFE standards focus on a Manufacturer’s fleet average fuel economy, rather than on specific vehicle models. As a result, large “loopholes” exist in the law undermining the goal of the law.

The following paragraphs describe key elements for a new Fuel Efficiency Standard

The enactment of a Model Average Fuel Efficiency (MAFE) standard, replacing the CAFE standard, would eliminate loopholes and give manufacturers specific goals and guidelines for each vehicle model.

Under a MAFE standard, fuel economy would no longer be expressed in miles per gallon (mpg). The MAFE would be expressed in miles per 100 million joules (MPJ), where the ‘J’ in MPJ would represent 100 megajoules. [Miles per ‘J’ = MPJ = miles per 100 million joules.]

The joule is the International Standard unit of energy. The gallon is an old English measure for a volume of liquid, which says nothing about energy. The CAFE is, of course, concerned about gasoline consumption and a gallon of gasoline is a common term recognized by all U.S. drivers, but it is not very scientific. Measuring fuel efficiency by MPJ instead of MPG would level the playing field between gasoline and alcohol fuels.

Gasoline versus Methanol:
The energy content of one gallon of conventional gasoline is approximately 122 megajoules (LHV*). The energy content of one gallon of methanol is approximately 60 megajoules (LHV).
*LHV=Low Heating Value. Gasoline's LHV should be compared with the LHV of Methanol. Low heating values are based on the assumption that the energy in the exhaust waste heat cannot be used. This is true for cars. (For home heating the heat in the water vapor can be captured and used, so HHV* is appropriate. *HHV=High Heating Value.)

An Alcohol Engine will produce 30-40% greater fuel efficiency than a gasoline engine, yet a gallon of methanol will still deliver fewer miles per gallon than gasoline. However, if the two fuels are compared using miles per 100 megajoules (MPJ), then methanol will deliver 30-40% better mileage than gasoline when fueling an Alcohol engine and will exhaust 30-40% less carbon dioxide per mile than gasoline.

Methanol is a preferred fuel for race cars because it is safer and produces greater combustion horsepower, per unit of fuel energy (measured in BTU’s or Joules), than gasoline when powering an engine optimized for alcohol.

Unlike race cars, the spark ignition internal combustion engines in automobiles are optimized for gasoline, not alcohol, because gasoline was significantly cheaper than alcohol and widely available for most of the 20th century. However, when the retail price of gasoline rises above $2 per gallon, methanol made from non-petroleum hydrocarbons will cost U.S. drivers less than gasoline (based on miles driven per dollar spent for fuel).

Opposition to expanding methanol production for the purpose of replacing gasoline is entirely political, there are no technology barriers—methanol can be produced from USA natural gas, biomass, coal and oil shale on a scale equal to the current volume of gasoline consumed in the United States.

Methanol is produced worldwide today using natural gas or coal as the base carbon source (feedstock). Technology also exists for large scale production of methanol from biomass. And, catalysts are currently being developed that will soon allow a shift from methanol to synthetic ethanol production.

The MAFE standard would not reward a manufacturer for producing an alternative fuel or flex fuel vehicle (incentives would be given through other statutes). The MAFE standard would apply only to vehicles that consume carbon based liquid fuels. The MAFE would not apply to electric vehicles or plug-in electric vehicles (PHEV’s).

The MAFE standard would apply to the fuel economy of a hybrid electric vehicle (HEV) in city traffic, but “potential” mileage gain estimates for a PHEV would not be included in the MAFE measurement for a given vehicle model (PHEV incentives would come through other statutes). The reason why PHEV's would not receive special MAFE treatment is because drivers might not bother to plug them in — a problem similar to flex-fuel vehicles that received special CAFE “credits” although it was well known that drivers were not filling up their tanks with E85.

Flex-fuel vehicles should be mandated for all spark ignition engines that use gasoline, rather than attempting to manipulate manufacturers through granting adjustments to fuel efficiency standards as incentive to produce alternative fuel vehicles.

Overemphasis on vehicle mileage has caused manufacturers to produce smaller and smaller cars in order to reduce the weight of the vehicle; an unintended consequence is increased risk of injury during an accident. In order to give manufacturers an incentive to make safe family size fuel efficient cars, MPJ (miles per 100 megajoule) would not be the only measure for the MAFE standard. The MAFE requirement for a given vehicle model would also set targets for the size and weight of the vehicle, related to the number of passengers that can sit comfortably in the vehicle.

American families want a large family car or van, unfortunately a four-wheel enclosed motorcycle (tiny car) isn’t going to give them what they want. The weight of a vehicle can be significantly reduced without reducing the size of the vehicle; this can be accomplished by replacing the steel body and interior steel parts with fiber-reinforced thermoplastic composite material, which is 60% lighter and 600% stiffer than steel.

The MAFE standard would set an objective for automobile manufacturers to produce a seven passenger family vehicle that gets 40 miles per 100 megajoules (MPJ) with outstanding safety, comfort and performance, built with ultra-light advanced composites to reduce weight without reducing size. The vehicle mileage calculations would not be adjusted for any “alternative” fuel or plug-in capability—the mileage would be based on real miles driven in city traffic, powered by the fuel type: gasoline, diesel or alcohol.

If a large family car or van can achieve the MAFE goal of 40 MPJ, calculated without the aid of PHEV enhanced mileage gains, then an 80 MPJ “tiny car” would certainly be possible too, which means that when PHEV capability is added to the vehicle model, the carbonless mileage contributed by the plug-in battery would begin where the vehicle’s MAFE target ends — a win for the family and a win for the environment.

Automobiles in the USA consume about 140 billion gallons of gasoline per year — gasoline burned in automobiles accounts for over forty-five percent of total U.S. oil consumption (9 million barrels per day).

The United States imports 6 million barrels of crude oil per day from OPEC nations. By replacing gasoline with non-petroleum American made alcohol fuels, the USA would completely eliminate dependence on OPEC oil—and set an example for the world to follow.

Current U.S. fuel ethanol production capacity exceeds ten billion gallons per year. Fuel ethanol produced in the United States today is made primarily from corn starch by the process of fermentation and alcohol distillation. In the future, fuel ethanol will be made from non-food biomass, using advanced technology that will extract sugar molecules from the cellulose portion of biomass fiber—a technology that has not been demonstrated at commercial scale. Yet there is no reason to wait—if synthetic alcohol is added to the mix, America has the resources required to completely replace gasoline now.

References:
Corporate Average Fuel Economy (CAFE)
CAFE Overview - Frequently Asked Questions