Ethanol Sources: Not Just Corn Alone

Switchgrass may bloom four or five times year, and because it is a non-food crop, it would not affect food supplies in any way. This grass also may be grown in a wide range of ground conditions, both wet and dry.(Photo: Warren Gretz/National Renewable Energy Laboratory)

While all that may be true, the problem with E85 is that there is no infrastructure in place, yet, to make it widely available to the owners of flex-fuel vehicles who may use it. Both GM and Ford are ramping up their marketing of flex-fuel vehicles over the next few model years so that when E85 is available across the country, the vehicles also will be there to use it. The Chrysler Group also may expand its low-level flex-fuel program from near dormancy.

Because these major OEMs have demonstrated they know how to build flex-fuel capability into their vehicles, the engineering and practical-use job has been done. So, until the new low-sulfur diesel fuel is fully available by late 2008, alternative fuels to gasoline are going to be considered, if much-improved fuel efficiency becomes a national goal. 

Preliminary estimates show that it is going to take a lot of corn - and a lot of time - to process into ethanol for E85 to become a widely used mix with gasoline. Sugar beets are another possible source for ethanol extraction, but, like corn, they do not grow rapidly and they are even less of a source in practical terms.

One Canadian company, Iogen Corp., believes a higher-volume feedstock for ethanol is switchgrass, which grows in the wild. Switchgrass may be harvested several times a year because it grows rapidly. Switchgrass also does not need much water to support its growth.

Close-up of switchgrass plants 210 cm in height.
(Photo: Todd Johnson/National Renewable Energy Laboratory)

Unlike corn, however, switchgrass is a non-food source, and it is essentially cellulose in its biology. Iogen executives say that switchgrass has the advantage of being five times more productive in yielding ethanol from a similar quantity of corn. The company claims that 75 gallons of ethanol can be processed per ton of switchgrass straw, with roughly two-thirds of the straw being converted into the fuel.

But a word of caution: Do not fall into the trap of thinking that we can bring about energy independence by adopting alternate fuels. Alternate fuels, such as E85, can bring us to a time when we are far less energy dependent on foreign crude oil than we are today, but gasoline will still be needed.

Breaking our dependence, however, could be at least 20 years away. It may also take a decision by government to recognize that E85 could be a fuel of our future. Not such a tall order - both Sweden and Brazil are heading in that direction as you read this.

Brazil has ample sources of sugar cane from which it makes ethanol, and the country expects to be independent of foreign sources of crude oil within the next few years. To get there, it is now on a major fuel conversion program in which the goal is to have all automotive transportation using ethanol as the national fuel.

Fast-growing trees, switchgrass, corn, and other crops and wastes are studied in laboratories, such as this one at the National Renewable Energy Laboratory. After they are planted and harvested, they are turned from biomass to ethanol and other biofuels. 
(Photo: Warren Gretz/National Renewable Energy Laboratory)

Sweden, long an environmentally sensitive nation, intends to be independent of offshore crude oil by 2025. To do this, its goal is to convert its motor fuels to pure ethanol by then.

Of course, ethanol is not as energy-intensive a fuel in terms of BTUs as gasoline. So we can expect a few changed realities in our use of ethanol as a blend with gasoline. E85 may get 20 percent less fuel efficiency when compared to gasoline. The other consideration in this changeover is going to be the future price of a gallon of E85. If the government neither provides incentives to nor supports E85, we could be paying $3 or more per gallon for E85 and be getting less miles per gallon as well. How's that for positive gains in reducing our energy dependence?

But, it's not all bad, even if we do not know what E85 will cost in the years ahead. Environmentally, the use of ethanol will help to reduce CO2 emissions, which are now credited with being a major cause of global warming. Controlling these emissions is another long-term effort.

President Bush opened up the energy dependence debate in his January State of the Union speech. But Bush leads us to believe that technology alone will lead us to energy independence. That's not a likely result if we continue to use gasoline, even as a blend-mix of E85, for our transportation energy. But if we can get close to eliminating 85 percent of the gasoline we put in our tanks, even if it takes several years, our energy dependence is sure going to be a lot less than it is today.