One of the tech threads I've been following is the engineering of photosynthesizing organisms that produce liquid fuels. This isn't the clumsy sort of biofuel we've heard so much of, and laughed so hard about, where stuff is grown, harvested, transported, and then stewed in some manner to produce a poor substitute for gasoline or diesel. Rather, the microorganisms excrete the fuel and keep growing.

One reference was a brief chat with J. Craig Venter, the fellow who broke the bureaucratic logjams on genomics.

We're using a unique type of algae that we've genetically engineered to turn sunlight and CO2 into C8 and C10 and larger lipids. . .

Because we actually have to feed them concentrated CO2, we can take CO2 streams from power plants, cement plants and other places. People view CO2 as a contaminant—they want to bury it in the ground or pump it into wells to hide or sequester it. We want to take all that waste product and convert it into fuel. . .

My team has discovered more than 20 million new genes, so we're in a biological universe. There are no fundamental limits. I think we're going to see the next 25 years as some of the most innovative in the history of science.

More recently another team has developed a Photobioreactor that functions much as the ones described by Venter. They claim an output of 20,000 gallons of biofuel per acre per year.

This one sounds even better.

In a new approach, researchers from the UCLA Henry Samueli School of Engineering and Applied Science have genetically modified a cyanobacterium to consume carbon dioxide and produce the liquid fuel isobutanol, which holds great potential as a gasoline alternative. The reaction is powered directly by energy from sunlight, through photosynthesis.

Using cyanobacteria rather than algae may have some advantages. Isobutanol seems a better output than ethanol.

Using the cyanobacterium Synechoccus elongatus, researchers first genetically increased the quantity of the carbon dioxide–fixing enzyme RuBisCO. Then they spliced genes from other microorganisms to engineer a strain that intakes carbon dioxide and sunlight and produces isobutyraldehyde gas. The low boiling point and high vapor pressure of the gas allows it to easily be stripped from the system.

The engineered bacteria can produce isobutanol directly, but researchers say it is currently easier to use an existing and relatively inexpensive chemical catalysis process to convert isobutyraldehyde gas to isobutanol, as well as other useful petroleum-based products.

I expect to read of ever better systems in the coming months. This is the beginning of a suite of technologies that promise better solutions to worries about CO2 and fossil fuels for transportation that those that are currently used, overcoming the legitimate objections of so many about biofuels.