Oil is running out. Our yearly usage of oil, coal, and natural gas are the products of around 1 million years' worth of organic matter converting sunlight to chemical energy, and unfortunately for us, much of our way of life depends upon the plentiful supply of petrochemicals. A Silicon Valley startup called LS9 might be holding a solution to this problem in the form of some cleverly genetically-engineered bacteria that are able to convert fatty acids into hydrocarbons that are drop-in replacements for carbon-based fuels such as gasoline and diesel.

No one can deny the massive impact that fossil fuels have had on human development over the past two centuries. As a fuel they have very high energy density at relatively low weight, making cars convenient and airplanes possible. As feedstocks for industrial chemical production, they make possible just about everything I can see on my desk, from the desk itself, to the pens and picture frame, all the way to the computer, LCD, and other peripherals.

However, that utility and ubiquity comes at a cost. Our carbon dioxide emissions are driving climate change, along with other forms of pollution, and the concentration of oil deposits in politically charged regions represents a geopolitical challenge that has much potential for instability and resource-driven conflict.

Biofuels are being viewed as a potential short-to-medium-term replacement, whereby instead of letting planet Earth do the hard work of converting plant material to oil over geologic timeframes, we humans do it instead. Corn-based ethanol and soy-based diesel represent the lowest-hanging fruits of the biofuel movement, with simple conversion processes, and a host of externalities that make them unsuitable for long-term use.

Getting little critters to do the work for us

It doesn't take a genius to think that a better solution would be to engineer organisms that can do the job for us, using biowaste or weeds rather than food, and that's exactly what LS9 have been working on.

Details of the technology they have been using are scarce, as they're a commercial entity and not a publicly-funded academic lab, but they appear to have engineered both yeast and E. coli bacteria to make use of "previously undiscovered metabolic pathways" to convert sugars into hydrocarbon products than can be put straight into your gas tank, or sent off to a refinery for processing. LS9 claims that this process is nearly carbon neutral, and is about 65 percent less energy intensive than ethanol fermentation.

The bit about the previously unknown metabolic pathway is intriguing; as far as I can make it out it involves modifying fatty acids inside the cells into simpler hydrocarbons which are then excreted, but since it's a trade secret, we don't really know much more. LS9 is attempting to scale up its technology into something that could work industrially; currently the largest reactor they have is 1,000 liters, which is impressive for a lab, but not really comparable to the millions of barrels of oil used each day in the US alone!

LS9 aren't the only company working on second- and third-generation biofuels; earlier this year I reported on the Corvette Racing team and their use of cellulosic bioethanol from KL Process Design Group, who brought the first commercial cellulosic ethanol plant on stream recently.

As promising as all these biofuel systems are, looking further ahead, there are bound to be better solutions. Using intensively-farmed crops as a starting point is less than ideal. Although it's not quite true that the production of corn for ethanol is responsible for the large increase in food prices and subsequent food riots across the world—petroleum products are involved at every stage of food production, including pesticides, fertilizers, transportation of those to farms, transportation of the crops once harvested and so on—they are often less than carbon neutral, and land given over to biofuel production is land that isn't being used for food production.

Even second- and third-generation fuels that use organic waste as a base for fuel production require processing and transport, and aren't always fantastically efficient. On the other hand, bioengineered algae, plants, or bacteria that could use a modified photosynthetic pathway to convert sunlight into fuel, whether it be hydrocarbon-based or even hydrogen, could provide truly effective replacements for our fossil fuel needs. Needless to say, smart people are working on making those a reality, but as with so much in life, it takes a lot of time. Whoever gets it right is going to make a lot money.