CELLULOSIC ETHANOL- THE PROMISES, THE PROBLEMS

In a previous post (KERETA SAWIT- THE TRUTHS), you might have noticed the mention of cellulosic ethanol (CE). For those who don't know, CE is a biofuel made by breaking down cellulose in plant matter and fermenting the resulting sugars. Unlike other ethanol (grain alcohol- which requires the simpler breakdown of sucrose), it does not require food crops, like corn kernels, sugarcane, etc. but can be made from any non-edible part of any plant.

Therein lies CE's first promise; it would have a much higher fuel yield. Since all plants are made up of cellulose, agricultural residue, forestry wastes, paper pulp, fast- growing prairie grasses and even algae could be used for fuel. Switchgrass yields up to 800 gallons of ethanol per acre per year, double that of corn, and equal to the current 'numero uno' ethanol crop, sugarcane, and one acre of algae could even yield up to 5000 gallons a year. These yields are augmented by the fact that CE crops can grow on arid, infertile land unsuitable for food crops. The potency of this combination of factors is revealed in the 2000 acres of algae farms in the Sonoran Desert that could double current U.S. ethanol production.

Plus, CE is also greener than petroleum, obviously, and other ethanol crops. Food crops require carbon belching technologies (aircraft, harvesters) during production, and sugarcane fields are burned to ease harvesting by hand. CE thus has a 85- 91% CO2 reduction compared to petroleum, which is greater compared to corn ethanol (22%), soy biodiesel (68%) palm oil (28%) and sugarcane (56%). CE crops also don't require soil- unfriendly pesticides, fertilizers or irrigation, and require less nutrients, besides causing less or no soil erosion, and providing wildlife habitats. Besides, bags of algae hung outside factories could soak up emissions.

Moreover, the economics (and politics) of CE also look promising. Adopting CE as our main fuel would save on petrol and other biofuel-crop subsidies, like corn. Governments and companies would also save on costs to defend Middle Eastern oilfields, and deprived of a global need for petroleum, Russia and the Middle East can no longer use fuel as political or economic leverage. Still, CE needs to be cheaper than petrol for these benefits to come through; its' current high price is the reason why it's not commercially produced. Since these costs have even forced temporary shutdowns of research reactors, a lot of work does need to be done here.

The next potential benefit of CE is its' actual usefulness as a fuel. CE can be used for almost all the current uses of petroleum; certain types of algae can be used to brew jet fuel. The energy ratios of CE also look promising; its' maximum of 1 unit of energy input to 36 units of enrgy output shames corn (1:1.3), sugarcane (1:8) pal oil (1:7), soy biodiesel (1:2.5) and even petrol (1:10.5). However, current production methods (heating with concentrated acids to hydrolyse cellulose into sugar) inlock only 45% of the energy available in plant matter, compared to the 85% unlocked during oil refining. Scientists, however, think they've found the answer: genetically modifying bacteria which digest cellulose in the guts of termites.

CE is thus in a position where its' surprisingly diverse promises could be killed by its' challenges, which pander to man's worst instincts of greed, mediocrity and molestation of the Mother Earth. These shackles have always restrained us as a species, but now, can we break them?

**For a longer, more detailed version of this article, leave a note in the Cbox, or drop me a comment, with your e-mail add. I'll send this to you as soon as possible. -Noel.