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My husband teaches in an agricultural school and he has mentioned this is as a much better choice than corn. No, its not a better choice than corn. What can be accomplished in the laboratory does not automatically translate into an economic opportunity.

First. The Cap Cost of constructing a cellulosic ethanol plant is $6+ per annual gallon. That means it would take over $600 million for a 100 million gallons per year plant. That compares to around $250 million to construct for a comparable grain based or corn based to ethanol plant.

Second, it takes 4 times the mass of switch grass or whatever biomass to produce cellulosic ethanol vs. grain based ethanol.

Third, to even come close to economically viable the cost of the biomass, switch grass, corn stover or whatever would need to be delivered to the plant site for less than $50 per ton. NO one is going to collect and transport biomass for that amount.

Fourth, if you are taking biomass from the farmers field such as corn stover, it will deprive the soil of badly needed nutrients provided by normally letting in rot in the fields. And fifth, the enzymes that will need to be developed to breakdown biomass to a form that can be fermented must be highly selective depending on the feedstock. Having so many enzymes available at a biomass cellulosic plant for use with the multitudes of different biomass feedstock will greatly add to operating cost.

The most economic thing to do with biomass if it can even bee collected efficiently is burn it to create the plant energy required to produce ethanol from grain. This will greatly reduce the cost of producing ethanol from grain based feedstick.

Economically, celullosic to ethanol is still a long way off and may never even become a reality.

“Third, to even come close to economically viable the cost of the biomass, switch grass, corn stover or whatever would need to be delivered to the plant site for less than $50 per ton. NO one is going to collect and transport biomass for that amount.”

Sure they will. It’s done all the time in the form of other type grasses known as hay. Hay very often sells for less than $50/ton delivered. I’ve sold a lot of it myself the past several years for much less than that.

“Fourth, if you are taking biomass from the farmers field such as corn stover, it will deprive the soil of badly needed nutrients provided by normally letting in rot in the fields.”

You could get more than one cutting off the switchgrass. More than likely what would happen is they’d take a cutting of switchgrass, allow it to regrow then move cattle in to harvest the regrowth and deposit nutrients back into the soil in the form of manure. No doubt you’re stripping nutrients but the same can be said of corn (which btw is a grass). The higher the yield the greater the nutrient loss no matter what crop you’re talking about unless it’s a legume which can fix nitrogen out of the atmosphere and even then your stripping P and K out even if you assume no N loss.

The nice thing about grasses is they can be grown on land which really isn’t suitable for row crop (marginal ground). There’s some hurdles to overcome here, but I see switchgrass as having much more potential than corn for ethanol production which should be rightly allocated to feed purposes.

Good post. I see lots of hype about biofuels. Everything seems to indicate the eventual viability of biofuels. We have prematurely committed to using massive quantities of biofuel before economic viability. The biofuel supporters will discount your concerns however. As long as the subsidies and mandates flow, they will tout the eventual viability of their dreams.

If switch grass is not viable on a large scale, we may be stuck with corn-based ethanol, a choice that no one wants except the farm states and politicians. The corn-based ethanol industry is addicted to permanent subsidies and mandates, a recipe for a boondoggle.