The Ethanol Controversy – Fuel from Cellulose

One of the greatest potentials of Ethanol is to be able to create the alcohol fuel from garbage plants and waste materials like switchgrass and wood chips or pulp.

Currently, most of the Ethanol produced in the United States comes from corn. As grain prices rise, popularity for the fuel goes down. And anyone can admit that it does seem ridiculous to use food-grade corn to make fuel.

But ethanol doesn’t need to be made from corn. As I pointed out in a previous article, “The Case for Ethanol“, recent advances in manufacturing specialized enzymes could negate many of the arguments made against ethanol.

First some background.

In order for yeast to create ethanol, they need an energy source. That energy source is primarily glucose – a simple sugar. Think of a molecule of glucose as being like a train engine. Now hold that thought!

Grains such as corn contain large amounts of carbohydrates and starches, but little glucose. Carbohydrates are kindof like if you hook three or four cars up to that train engine. Starches are even more complex, so they are like adding 8 or 10 cars to that train.

But our little yeast cells can only handle one train car at a time.

So enzymes have been isolated that can break these carbohydrate strings down (a process called hydrolyzation) into simple sugars – making them digestable for yeast. So this is where the train cars are broken apart and dealt with as individuals rather than an entire train.

But there is a whole lot more plant material OUTSIDE the seed than inside it. This material is called Cellulose. It makes up the fiberous material in a plant’s stem, leaves, trunk, and roots.

Cellulose is like a really, really long train. A train with up to 9,000 cars (glucose units) attached. That’s why it’s so dang tough.

Now, the enzymes that have been used to do this process in the alcohol industry are only capable of breaking down carbohydrates and starches (the little trains) - and only after they have been fairly well torn apart mechanically and boiled to soften them up. These enzymes couldn’t even begin to chew up a tree’s roots.

So, the holy grain in the ethanol industry is to see who can come up with an enzyme that can break cellulose down into glucose.

The Holy Grain of Ethanol Has Already Been Found

In 2004 the Cellulosic Ethanol industry was born with the opening of a plant in Canada by Iogen Corporation. This plant processes 40 tons of wheat straw into ethanol per day. They use enzymes that they manufacture themselves, and have plans to roll this technology out worldwide.

So, what does this mean?

This means that fairly soon we could all be driving cars powered, at least in part, by things like grass clippings, waste from the lumber industry, and switchgrass from non-arable lands. It also produces approximately 85% less carbon dioxide than gasoline.

And the best part is that the fuel regrows itself every year. It is basically solar power that has been liquified in a distillation column.

Next Post: Debunking the Myth that Ethanol Plants Use Too Much Water