Monday, February 28, 2011

Synthesizing Diesel Fuel Using Cyanobacteria

A US firm called Joule has bioengineered cyanobacteria to secrete diesel or ethanol. The picture above is from the Washington Post version of the story and shows panels containing the organisms. But as is the case with other recent inventions the economics are not yet clear. The company claims they could produce fuel at $30 per barrel - a third of the current price of crude oil. They also claim that they can produce 128 tonnes of fuel per hectare. Yields of grain crops are usually measured in single digits of tonnes per hectare... Even so, I computed that it would take the area of California, Japan, or Sweden to supply the world with the current level of oil consumption.


  1. It sounds bad when you think of losing CA, Japan or Sweden, but consider: that's also the size of Chita Oblast, smaller than the Yukon Territory, about the same as North Darfur + Indiana ... now you're talking about much less powerful constituencies and cheaper land!

  2. Yes, you are right that it does sound different :) Something like this would require plenty of sunlight and water I'd think... My point wasn't so much the land area lost but imagining these kinds of arrays covering an area the size of California and the oil still only costing $30 a barrel or to point out just how much land is needed to supply all our energy needs from biofuels using grain crops which yield a small fraction of this supposed yield.

  3. Count me a sceptic. How do they stop the invasion of wild strains of cyanobacteria, that can put their photosynthesis effort into growth and reproduction rather than producing useless (to the organism) oil or toxic ethanol? How do they control pest invasion?

    What ranges of micronutrients, water purity, temperature, and light levels are acceptable? What assumptions are they making about costs and return on investment? One lab technician for every hundred square metres of panel isn't going to work. Using 50% of production to power the recirculating pumps and oil separators or distillers is unlikely to be workable either.

    How do they harvest? What is the quality of the produced oil? (If, for example, it's high in aromatics, it's not going to be wanted.)

    Quite likely the NREL spokesperson has seen several "breakthrough' technologies come and go, because they can't scale up from the lab or pilot study to commercial plants - the "breakthrough" can't, in fact, break through. Professor Pienkos is greatly understating the difficulties in sayng that the company faces "complicated engineering issues".

    Robert Rapier, an engineer who has been working in biofuels for several years, has a blog in which examines technologies of this sort. It's worth reading his posts on questions to ask companies touting for investment. His blog is at

    Don't get me wrong: I'd love to see a viable, nonfossil, environmentally friendly replacement for liquid fossil fuels at the global scale. The sooner the better. But I don't think this is it.

  4. I agree with everything you wrote. There are so many questions and yet the $30 a barrel number is reported. I'll admit that I haven't read the paper they are supposed to have put out. Maybe all is explained there.

    Will check out that blog.

  5. Cyanobacteria cannot be compared to long time accumulated and stored energy i.e. oil. nothing can and its all about the quality-energy kind.

    Ecological economics needs to work out a complete science platform, which never going to happen. You only cost energy with no contact to environment neither concern of it.