Sep
25
Pipe dream to tailpipe?
Filed Under Science, Technology, Environment/Energy, Wired, Recent stories
My latest feature for Wired, about the science of cellulosic ethanol, begins its run on newsstands this week. The full story is also online, here. That’s a stalk of switchgrass adorning the cover, but the cellulosic ethanol described in the story actually involves making fuel from a wide variety of different plants—e.g. poplar trees, wood chips, other grasses. (Call it editorial discretion, but illustrating the cover line “THESE PLANTS ARE THE FUTURE OF ENERGY” might have cluttered things.)
The current method of producing ethanol (in the U.S.), from corn kernels, has been much castigated in the news lately. Although it seems a lot of the ethanol backlash is only tenuously based on actual research (especially when it comes to the energy balance of what goes into corn ethanol versus what you get out), there’s little doubt that corn ethanol has serious problems, enough to at least call its massive subsidies into question.
There is, however, another way of making ethanol, using a biological or chemical process to extract the cellulose, or “structural” part, from plants (rather than the starch, as in the case of corn ethanol, or the sugar, as in the case of the sugarcane ethanol in Brazil). Cellulosic ethanol usually makes the last couple paragraphs of ethanol stories; it’s declared to be some indeterminate number of years off, a biofuel holy grail awaiting a scientific breakthrough. There is general agreement that if we could make it, cellulosic fuel avoids most if not all of the problems of corn ethanol. Meanwhile, our federal energy targets (which are closer to hopes than targets, really) essentially assume that hundreds of millions of gallons cellulosic ethanol will soon be arriving. So, what gives?
My piece tries to lay out the history of the field (which actually dates to the 1970s), explain just what science needs to be done make it a reality, and profile some of the people doing that science. Some of the most fascinating work, to me at least, involves scientists scouting the world examining the excrement of rhinos and the stomachs of termites, looking for cellulose-digesting enzymes they can harness to make fuel.
The definitive-sounding take of the headline and cover undoubtedly give the piece a tint of undue optimism, but hopefully a closer read of the story itself reveals a careful effort to explain the state of affairs. In the end it’s tough to come to a conclusion beyond….cellulosic ethanol is some years off; but we try to make the case that the funding and research is now in place, for the first time, to determine whether cellulosic ethanol can become a commercial reality. Dozens of bio-refineries in the works, and hundreds of millions if not billions of dollars in research, are about to answer that question.
Personally, as is mentioned in the story, I don’t believe alternative fuels of any kind can make much of a climate change dent alone, without higher fuel economy standards, conservation, and maybe (I’m still undecided on this) a carbon tax. Cellulosic ethanol, however, could be a huge factor on the fuel replacement side of things.
This entry was posted on Tuesday, September 25th, 2007
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2 Responses to “Pipe dream to tailpipe?”
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Evan,
I was sent a copy of your ethanol article. I very much appreciate that you got it right about the problems associated with making ethanol from modern row crops with their massive energy inputs, run off problems etc. The amount of carbon dioxide released and the amount of water degraded in the making of ethanol are yet other concerns.
My greatest concern is that we need to rethink the whole idea of a replacement strategy. Your article falls into the category of supporting replacement of one liquid fuel, gasoline, with another, ethanol. Is this wise?
The demands for fiber-based solar energy that we will place upon our fields and forests require us to use these precious resources with the utmost care. We must extract the maximum useable energy we can in the smartest way possible. I suggest that a replacement strategy based on ethanol badly fails this test: It is neither smart nor does it maximize the useful energy.
Would it be better to have a DISplacement strategy AFTER intensive conservation? What if we displaced as much liquid fuel used in stationary energy demands with solid biofiber fuels? Then this “DISplaced” liquid fuel could be repurposed for transportation — after the demand for liquid fuels had been reduced by plugin hybrids.
As for ethanol from corn, it is indisputable that we get the most useful energy from corn if we BURN the kernels directly to produce thermal energy. This is backed up by a least one serious research paper. Converting corn to ethanol is disrespectul and wasteful.
Consider, further, that our current, centralized, grid dependent electrical system wastes around 80% of the energy put into it — heat we through away because our massive generators are “not in my back yard” combined with distribution loses.
We clearly need to move to a distributed electrical system built upon Micro-CHP and CHP at every point of demand. There is every reason to believe that these CHP units can be fueled with a combination of sunlight making steam as well as solid biofiber fuels. Solid biofiber fuels are, after all, a form of recent sunlight made useable: Green Coal.
This suggest that we need to ask a new and different question : How can we minimize our use of liquid fuels for energy production? Not “How do we maximize liquid fuel production.” We need to think out of the box, as replicating the in box solutions, even if we change the liquid used, will not get us to where we want to be.
I look forward to hearing from you.
Regards,
Jock
So I’m clearly a couple months behind with Wired, because I just read your piece on a flight today. As I’m reading along I realize, “wait, I think that’s EVAN Evan.” :)
Congrats on the cover - great piece and I’m really excited to see where this goes. Hope to see you soon!