Cellulosic ethanol

One of the most intelligent things I've read on ethanol production lately comes from an anthropologist:

It seems to me that most of these drawbacks come from insisting on a monoculture, which -- if you have an efficient cellulose processing capacity -- I don't see why you care about. A real natural marsh or tallgrass ecosystem can't stand much mowing, but if you could tune a multispecies ecology for biofuel production, that would pose much less risk of invasive potential, and would be less trouble to look after. The tallgrass ecosystem was based on burning, anyway, so you should be able to maintain the soil while taking out hydrocarbons with minimal fertilizing.

Good insight, this. Cellulose is, for the most part, cellulose. At the point we commercialize cellulosic ethanol, it doesn't matter what the crop is. Just take whatever grows best locally and run with it.

I still think crop based biofuels are only a short term and/or small part of the solution. We can reduce our energy consumption many, many ways. We still need to eat. But if cellulose can be harvested from otherwise un-farmed land, maybe in lieu of prescribed burns, it'd be a win-win situation.

Biofuel Folly?

There has been a lot of hype around biofuels over the last year or two. Any sane person can see that corn based ethanol and soy or palm based biodiesel are just plain silly. Switchgrass based ethanol is definitely a step up from corn (if we can ever commercialize it). Crop based fuels have the additional problem that we have to use land that would otherwise produce food (or remain virgin forest in the case of sugar cane or palm) to get these meager energy increases. The land is more valueable in other uses.

So why are we still hearing about corn? Because it can be done today. Never mind that it's not much of an improvement over fossil fuels. There is a big lobby behind it and it gets results now, even if the results are not worth anything. Thankfully, we're starting to hear some vocal opposition to these fuels from some sensible folks.

Photovoltaics and concentrating solar arrays can produce 100 times the energy per acre of corn ethanol. The problem is energy storage. Fuels are just more effective than batteries at storing energy for long times.

It seems algal biodiesel is the clear winner for biofuels. The energy produced per acre is much higher than even cellulosic ethanol, it uses much less water, and can be produced in locations with little or no agricultural value.

Corn based ethanol

Environmental groups finally seem to be speaking out against corn-based ethanol. I guess they finally feel that the alternative fuels movement has enough momentum that it's safe to start picking off the bad ideas. Corn just doesn't have the energy content to be effective. Generous estimates say you get about 1 and 1/3 times the energy from corn based ethanol compared to the (non-solar) energy that goes into producing it. In the process you lose a bunch of food.

But it's not all bad that there has been a big push for corn-based ethanol. It's going to push the development of infrastructure and ethanol burning engines. This should further spur the development of cellulosic ethanol, and when that arrives, we will be ready to take advantage of it.

Keep in mind, though, that alternative auto fuels are only a part of the solution to the energy problem, with is only part the large global issues we are facing.