Doing it in the Dark: Fuel from Thin Air, and beyond Light
by Jim Lane (Biofuels Digest) Beyond biomass, beyond fossil fuels, beyond light itself. And now, the direct production of drop-in biofuel blendstocks. All available from a microbial “cow”.
This week in California, a research team from Shota Atsumi’s lab at the University of California, Davis have reported that they engineered Synechococcus elongatus PCC 7942, a strain of photosynthetic cyanobacteria, to grow without the need for light.
…In meat production, you use the animal directly and slaughter it in the process. In milking, you use the animal’s byproduct, and the animal lives. Is it more efficient to make biomass, then kill it, then transform it into something useful, or simply to make it into something useful from the start?
One limitation? The problem of light. Imposing some limitations on the production of targeted products to the daylight hours — more importantly, restricting the locations to places that had good solar insolation. Which don’t always line-up perfectly well with the availability of water, or CO2, or low-cost-land. Plus, you had the problem of photosynthetic efficiency itself — which never gets above 10 percent (a fraction of the efficiency of solar PV).
That was one of the reasons why our March report on “Biofuels from a raging fireball? No fossil energy, no light, no biomass, no sugars. No kidding” drew so much attention.
“Where the hydrogen coming from?” asked a number of astute readers at the time. And for sure, it was coming not from water, but from hydrogen gas. Which is generally made from fossil fuels (though it can be made renewably).
So, how is this latest news from UCD an advance of the storyline? In two ways — one, we haven’t seen the requirement for hydrogen gas: water seems to be able to provide the hydrogen. Secondly, we note that the targeted products that Bossie can make include, to date, isobutyraldehyde and isobutanol.
The former, a precursor for the synthesis of other chemicals, and the latter is the well-known gasoline substitute that companies such as Gevo, Butamax and Green Biologics are chasing. Isobutanol can be directly blended as a gasoline feedstock, today. READ MORE