Thursday, November 13, 2008

The Promise of Cellulose Ethanol

Ethanol has emerged as the premier alternative fuel to replace gasoline and lessen our dependence on fossil fuels. In Brazil for example, 8 out of every 10 cars on the road already run on ethanol derived from the sugar cane plant. In part, the United States is the largest producer and exporter of ethanol derived from corn. But is it a good idea to use a food source to produce a fuel? By the current rising costs of food and commodities, there's a very strong case against the idea.

Enter Cellulose

Cellulose is one of the most abundant organic molecules on earth. It is found in most plant matter. It has been found by many scientists to be the answer to the search for an alternative source of ethanol. Cellulose ethanol is basically ethanol derived from organic matter such as wood chips, prairie grass, switch grass, and even saw dust. These sources of cellulose ethanol can be found in a lot of the waste material in such fields as construction, farming, the lumber industry, and even landscaping. All this waste material is given the term "biomass" by scientists.

It is estimated that the United States alone can generate around 500 million tons of biomass per year. This yield would enable the production of about 40 billion gallons of cellulose ethanol annually, replacing about 25% of the total gasoline consumption in America today. The importance of getting cellulose ethanol online is quite evident, but the transfer process is a gradual one. Cost effective ways to produce cellulose ethanol are being developed and optimized, and a substantial infrastructure of production and deliverability is on its way. Further more, it is imperative in the process of commercial production of cellulose ethanol to lessen the yield of any more greenhouse gases into the atmosphere.

Cellulose Ethanol

The process of making cellulose ethanol is pretty close to the same process of making moonshine, but with a few other steps. The biomass material is first churned into fine particles and pretreated with an acid to start the breakdown process. It is then soaked in a high temperature container for several days as enzymes break down the cellulose molecule into simple sugars. The sugar is then fermented through a form of yeast or bacteria. Fermentation is basically the consumption of the sugar by the yeast, yielding fuel grade cellulose ethanol as a waste byproduct. The cellulose ethanol is then distilled from the sugar/yeast solution.

Like any other technology, it is through the passage of time and through consistent honing of the technology that the production costs are reduced and the yields are maximized. It is an evolving process whereby scientists discover better and more efficient ways to produce cellulose ethanol. The first commercial facility to produce cellulose ethanol from biomass is due to come online by 2011 in the Midwest region of the United States.

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