Nobel Prize biophysicist: "The Nonsense of Biofuels" [Fritzworth]

Ash Jogalekar (himself a scientist) reports at his website on a scientific editorial, "The Nonsense of Biofuels", written by Hartmut Michel, who won the Nobel Prize for his own research into biophysics. The gist of Michel's editorial (which is not accessible, Jogalekar's link notwithstanding) is that there just isn't enough efficiency in biophysical processes. Open it up for an extended quote from Jogalekar's post.

All these hurdles lead to a rather drastic lowering of photosynthetic efficiency which gets watered down to a rather measly (but still staggeringly efficient by human standards) 4% or so.

It's pretty clear from this description that any kind of efforts to get better efficiency from biofuels will have to overcome enormous protein engineering hurdles. This does not bode well for current studies aimed at such goals. While these are very exciting from an academic standpoint, they will have to lead to a very drastic retooling of the basic photosynthetic apparatus, involving re-engineering numerous genetic pathways and their products, to be of large-scale commercial value. It's all too easy to underestimate the sheer amount of energy that we want to generate from these technologies. I feel the same about the synthetic biology efforts that seek to produce all kinds of valuable industrial chemicals and drugs from engineering bacteria. These efforts are undoubtedly promising, but getting bacteria to do something which they have not evolved to and that too on a scale rivaling the fossil fuel industry is a very long shot indeed. Michel doesn't even seem optimistic about the recent excitement regarding biofuel production from red algae, and reading his prognosis one wonders how much collaborations such as the one between Exxon and Craig Venter are actually going to yield....

The core issue with most "green" forms of energy is that they lack "energy density", as the late SF writer James Hogan put it a few years ago in his essay "Nuclear No-Contest". As Hogan points out:

If the way forward into the future calls for higher energy densities, the notion that we can depend on solar or wind (which is another form of solar) represents a move backward. To get an idea of just how dilute a source solar is compared even to coal, consider a lump of coal capable of yielding a kilowatt-hour of electricity, which would weigh about a pound, and ask how long the Sun would have to shine on it to deposit the same amount of energy that the coal will release when burned. The area of its shadow, which measures the sunlight intercepted, would be about fifteen square inches. In Arizona in July, with a 24-hour annualized average insolation of 240 watts per square meter, it would take 435 hours, or almost three weeks , for this amount of surface to receive a kilowatt-hour of sunshine. For the average location in the U.S., allowing for bad weather and cloud cover, a reasonable estimate would be twice that. But to obtain a kilowatt-hour of electricity, at the ten to twenty percent efficiency attainable today, which appears to be approaching its limit, we'd be talking somewhere between thirteen and seven months....

I wonder if the people who talk glibly about attempting to match such feats artificially really comprehend the scale of the engineering that they're proposing. A 1,000-MW solar conversion plant, for example – the same size as I've been using for the comparisons of coal and nuclear – would cover 50 to 100 square miles with 35,000 tons of aluminum, two million tons of concrete, 7,500 tons of copper, 600,000 tons of steel, 75,000 tons of glass, and 1,500 tons of other metals such as chromium and titanium – a thousand times the material needed to construct a nuclear plant of the same capacity. These materials are not cheap, and real estate doesn't come for nothing. Moreover, these materials are all products of heavy, energy-hungry industries in their own right that produce large amounts of waste, much of it toxic. So much for "free" and "clean" solar power.

posted by Open Blogger at 02:44 PM

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