The energy moguls expect switchgrass to be a major replacement for petroleum. Why do you suppose it hasn't happened yet? They have the biggest research laboratories in the world working on it, from Oakridge to Stanford. And this is why it isn't happening. Anything that needs that much research is not going to be competitive with something which is piped out of the ground like oil.

The problem is economics. Brazil virtually replaced gasoline with ethanol by using sugar as the raw material. Sugar only requires one step of processing, which is fermentation. Americans start with corn as the raw material for ethanol, and it requires two processing steps. First, the starch must be broken down into sugar, and then the sugar must be fermented. Switchgrass requires many steps of processing. There is no way to eliminate those steps, and there is no way to make them cheap enough to compete with petroleum.

Here's what the task is: Only the cellulose in switchgrass can be converted into ethanol. It breaks down into sugar, just like the starch in corn does. But the difference is that corn starch is nearly pure, while the cellulose in switch grass is embedded in large amounts of biological material including proteins, lignin, genetic material, chlorophyll, lipids and small molecules. That debris must be separated from the cellulose, before the cellulose can be broken down. Normally, enzymes would be used to break down the cellulose, and they cannot function effectively in the presence of such debris. This problem is what is holding up the process. Separating the debris is too expensive, and enzymes are not efficient in the presence of debris.

The researchers would be looking for substitutes for enzymes which could function in the presence of the debris. This would allow fermentation without separating the debris. But there are not good substitutes for enzymes. The substitutes will be inefficient compared to enzymes, and this will increase the cost.

So the whole question is this: Will researchers find a magical way to break down the cellulose in switchgrass? It won't happen. Biological molecules are too complex for substitutes for enzymes.

Another problem is that the enzymes for breaking down cellulose are not produced by bacteria or yeasts, which are extremely easy to grow in large quantities of liquids. Cellulose is normally broken down by molds, which are not easy to grow in liquids. Therefore, there would probably be a problem of expense in using massive quantities of enzymes to overwhelm the debris in the biomass.

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The most recent procedure, a supposed breakthrough, is the use of a catalytic procedure to convert cellulose into a gasoline-like product containing aromatic compounds. The problem is that the nitrogen containing debris still has to be removed. Removing it is expensive, and disposing of it creates an environmental problem.

It is said that trucking switchgrass or corn refuse more than 20 miles is impractical, because those materials are so light and bulky. Enough cannot be produced in a 20 mile radius to justify setting up a processing plant. This problem eliminates the whole concept of using agricultural sources of cellulose regardless of the method of processing.

So why is the research even continuing? Because scientists go for a noble purpose to justify expensive research. And propagandists do a lot of pretending. They are still exploiting the pretense that alternative sources of energy, or green energy, are just around the corner.