Basics of photosynthesis. Source: Tracy Wilson, Science.HowStuffWorks.com
Photosynthesis is a concept I’m sure many of you are aware of. It is often one of a schoolchild’s first forays into the scientific world. At its most basic, photosynthesis is the process by which plants (and some algae) take carbon dioxide, water and sunlight, and produce carbohydrate and molecular oxygen. Sunlight is obtained by chlorophyll, the pigment which gives plants their green color, which initiates the entire process. Often times, the photosynthetic reaction is written as follows:
CO2 + H2O + Sunlight = C6H12O6 (glucose) + O2
The products of photosynthesis, sugar and oxygen, are essential to life on this planet. It is no surprise then that this incredibly efficient mechanism of energy production has become a hotbed for research in the scientific community.
Many researchers are currently looking into the possibilities of cost-effective artificial photosynthesis (AP). While a novel pursuit, there has yet to be much success in this regard. The main issues facing scientists are monetary concerns, as the materials needed to artificially harvest CO2, H2O and photons of sunlight are quite expensive. Add to this the fact that energy production via fossil fuels is much cheaper in comparison, and scientists definitely have their work cut out for them. Fortunately, certain sectors of the scientific community are still hard at work on making AP a reality, such as the company Sun Catalytix, who have developed an eco-friendly artificial leaf capable of sun harvesting. While they have yet to achieve prices comparable to that of fossil fuel energy production, they are headed in the right direction. It’s safe to say that the implementation of artificial photosynthesis (and the subsequent move from fossil fuels that would result) would be a momentous step for humankind.
Of course, it’s never wise to put all of your eggs into one basket. In that regard it is important that we look into other ways in which we can incorporate aspects of photosynthesis into technology. As it turns out, some animals are able to mimic photosynthesis. Remember those photosynthetic algae I mentioned earlier? Those come into play now in a huge way. Consider the sacoglossan sea slug Elysia chlorotica, for example:
The solar-powered sea slug, Elysia chlorotica. Source: http://eol.org/pages/450768/overview
This creature is able to “steal” the chloroplasts from algae, incorporate them into its own body, and continue photosynthesizing for as long as a year afterwards. Many other animals are capable of stealing or sharing chloroplasts and creating their own energy as a result. How exactly it is done is not completely understood, however this does raise some interesting questions. Primarily, is there a way we can take chloroplasts and incorporate them into light harvesting technology? Or better yet, can we mass produce synthetic chloroplasts and incorporate them into technology such as the silicon leaf created by Sun Catalytix? The future is bright, and artificial photosynthesis is becoming a more realistic possibility by the day.
Cruz S, Calado R, Serôdio J, Cartaxana P. Crawling leaves: photosynthesis in sacoglossan sea slugs. Journal Of Experimental Botany [serial online]. December 15, 2013;64(13):3999-4009. Available from: Academic Search Premier, Ipswich, MA. Accessed November 20, 2013.