Micro-Biofuel

Our final renewable rock star, biofuel actually winds up living a double life. Not only is it considered a green energy source, but it is also a cousin to fossil fuels. Whereas, fossil fuels are derived from organic matter that has been liquified by pressure from centuries-worth of rock deposits above and the blistering heat of Earth’s core below, biofuels come directly from brand new plant matter.

Due to its muddled heritage, biofuel lays low and may not be as well-known as the clean energy poster children, wind and solar. Nonetheless, biofuel is liquid fuel from various biological sources such as corn, beets, rice, and so on, and is typically used in transportation. One such example is ethanol, a substance currently in use, but that must be combined with gasoline in order

Biofuels, like gasoline, are still burned and still produce the big, bad greenhouse gas: carbon dioxide! So, how can they be considered a clean energy?

But since plants absorb carbon dioxide, the logic is that the same amount of gas released when it is burned is precisely the amount of gas that the plant took up. Consequently, there is no net change in the amount of carbon dioxide in the atmosphere, but rather a cycle of sorts. But it should also be noted that we must strive for a net decrease in levels of atmospheric carbon dioxide gas rather than settling for no change.

Plus, growing crops and converting them into energy requires space, energy, and different pollutants such as pesticides, rendering biofuel an inefficient energy source. Some insist that biofuel from cellulose, a substance much more dense than ethanol, is the fuel of the future. Others, however, are all about micro-bio fuel, or more specifically fuel from microbes!

Does the name Escherichia coli or E. coli ring a bell? Sure, some strains of E. coli cause those food poisoning incidents undoubtedly coming to mind, such as the Chipotle outbreak of 2016. But other types of E. coli hang out in our digestive tracts without harming us. In fact, these species can help us by degrading different nutrients from our food.

But E. coli is also the poster child for bacteria and genetic engineering. When I worked in a molecular biology lab, we strictly used E. coli for amplifying plasmids, that is producing large amounts of small DNA bubbles. Not only are several strains of E. coli perfectly safe, but we also know a considerable about E. coli and its genome. Plus, E. coli is a fairly robust bacterium and has fairly effortless dietary requirements. Scientists are also creatures of habit, and we’ve been using E. coli in genetic engineering for decades.

But for this brand of micro-biofuel, E. coli was not a mere tool used to genetically engineer something, but rather the subject of genetic engineering. Researchers at UCLA, have designed E. coli to produce different types of alcohols that might have more favorable qualities than ethanol. For one, high chain alcohols lack the volatility and corrosiveness of ethanol, and therefore would be less damaging to gasoline tanks and other aspects of automobile engines. By sampling messing around with a few of E. coli’s metabolic pathways, these scientists can produce tremendous amounts of these modified biofuels, from a bacterium no larger than one thousandth of a millimeter across.

But similar to biofuel, these alcohols would release carbon dioxide when combusted.

But another slightly distinct effort is taking place at Texas A&M, where a professor has plucked six genes from E. coli’s DNA, and consequently given the bacterium the superpower to produce more than 140 times more hydrogen than usual. This hydrogen can be employed in hydrogen fuel cells. This technology facilitates a reaction between hydrogen and water gas to produce water and yield energy.

Although this technology has been around for a decent amount of time, the process by which hydrogen was generated previously, called “cracking” requires a lot of energy and costs a pretty penny.

Of course, there are flaws with this issue, such as figuring out how to transfer massive amounts of explosive and flammable hydrogen gas, but the implications of using E. coli for energy are boundless. I mean we already use these handy bacteria for genetic engineering and vaccine production, what’s one more green application?