Important, albeit somewhat depressing, post about biofuels from algae on chemical engineer Robert Rapier’s always excellent blog.

Here’s his introduction to the article, which you should read in its entirety:

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The following is a guest post by John Benemann. John has many years of expertise in biomass conversion, and previously co-wrote a guest piece on cellulosic ethanol. On the subject of biodiesel from algae, he literally wrote the book.

I originally wrote an article over a year ago in which I mentioned the potential of algal biodiesel. I still believe, as I did then, that biodiesel (or more broadly, renewable diesel) is a far superior fuel to ethanol for reasons I outlined in that essay. However, over the past year, the more I learned about the prospects of biodiesel from algae, the more it started to look to me like cellulosic ethanol: Technically feasible? Yes. Commercially feasible? Nowhere close, and the prospects don’t look good any time soon.

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This was a bit disheartening for me, because I had high hopes that we had an option for replacing a large amount of our fossil fuel usage. I no longer believe that, and recent work by Krassen Dimitrov (PDF warning) had reinforced my doubts. When I read the guest post at The Oil Drum by fireangel, “Has the Algae Cavalry Arrived”, my first thought was “Nice work.” My second thought was, “I should have jumped on this and investigated thoroughly eight months ago when those nagging doubts started to creep in.”

But should there be any further doubts, here is a guest post from a man who knows as much about this subject as anyone else in the world. And he bears bad news for those who had visions of driving around in algae-fueled transportation.