We are really messing with mother nature on this one. We are taking one of the central biological functions in nature, one that was a mystery up until modern science, and we have made it mechanical. Not only have we been successful in duplicating it, we have found a way to use it to our own advantage, as a sort of assembly line for resources we can use.
That's pretty wild.
What is this secret of nature that we have successfully modernized and manipulated, you ask? Well, as an article in Scientific American describes, scientists at Harvard have created artificial photosynthesis. This process begins with a solar panel that collects sunlight and uses that energy to breakdown water molecules. Microbes then take the hydrogen from this reaction and carbon dioxide from the air to produce alcohols, mainly isopropanol and isobnutanol. Artificial photosynthesis has been accomplished before, but what sets this attempt apart from those of the past is its efficiency, as the title of the article states, this process is ten times more efficient than natural photosynthesis, and the fact that the new alloy being used isn't poisoning the microbes, like in previous attempts.
One thing that confused me about this article was how these alcohols were being created. From what we learned in sophomore biology, alcohol is created in cells through the process of fermentation, something that is only a secondary response, a sort of back up plan for the cell. It occurs when there is not enough oxygen present to perform cell respiration, the cells main way of transforming the sugar produced by photosynthesis into usable energy. In this system, however, there should have been plenty of oxygen present, as the process that creates the hydrogen needed to power the microbes also produces oxygen, oxygen that is not being used. I would be very interested in finding out how they circumvented the cell's natural function in order to prompt the fermentation process, because that must have been a challenge, at least in the early phases of the concept.
Another thing that caught my attention in this article was the practical application they describe. The primary application mentioned in the article was the use of the produced alcohol as fuel for people without funds or access to more common fuel sources. This struck me as odd, because I have never heard of the mentioned alcohols being used as fuel before. Even after some light googling the only trace I found of either of the alcohols in relation to fuel was use as a fuel additive, something to boost efficiency, but not as power itself. Maybe I missed something, as I didn't dig that deep into the internet, but some searching into the structure of the alcohols, and of gasoline showed that both consisted of the same elements (carbon, hydrogen, and oxygen) and both featured hydrocarbon bonds. This similarity in structure suggests that perhaps they could serve similar functions. Maybe I found no mention of alcohol being used as a fuel because for some reason, it hasn't happened before. Perhaps there was no efficient way of truly mass producing it until now. If this is the case, the prospect, whether plausible or not, of being able to provide alternative types of fuel or new production methods is truly noteworthy, as our limited resources on earth dwindle, and fuel prices grow. If this method can be widely used, and the product function effectively, it could change the way we power our world.