Life on Earth Owed to the Sun

Ominous black clouds formed overhead as we drove down the highway. I heard a crash of thunder, and the first drops of rain spattered down. I looked to the side of the road and saw a building with rows of solar panels in front of it. To my surprise, the water droplets that touched the surface sizzled and made a small pool of foggy steam above the blue cells. “When the solar panels get so hot, their efficiency must surely be reduced,” I speculated, remembering the bright sunlight and scorching heat from only a few minutes ago.
Life on Earth owes its existence to the Sun. The Sun’s immense ongoing nuclear reaction envelops us in its warmth and brightness, and enough of its energy reaches Earth in a day to power our world for a year. We can harness a fraction of this energy by using solar cells, which utilize the photoelectric effect to create electric current from the photons in sunlight (1, 2). Could it be that solar cells’ reduced efficiency due to overheating from the sun precludes them from being the clean renewable energy source of the future? Research on this topic indicated that this is, indeed, a shocking truth.
Solar cells are made of layers of semiconductor material, which expand at different rates when heated. This moves electron junctions apart, or places where electrons can ‘jump’ from one layer to another, and thereby drastically reduce the voltage (2). The most efficient solar cells today (multijunction devices of InGaP/GaAs/InGaAs) have reached around 35% photon-electron conversion under laboratory conditions (1). I was flabbergasted to learn how inefficient commercial solar cells are and became intrigued with the prospect of increasing their efficiency. Solar cells work by allowing photons to knock electrons loose ...

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...ter or saline waters of the ocean, opening up opportunities for novel aquatic solar energy collection. Placing solar cells just below the surface of the seawater would not only result in active cooling, but also make them more efficient and allow large-scale electricity generation. I believe this is only one of the many ways the results of my experiment can be implemented in real life. As I demonstrated, specific liquid mediums can be used to increase the efficiency of conventional solar cells by as much as 6%, just by implementing something as simple as a layer of aqueous solution above the solar cells. Applying this promising strategy can transmute solar panels into a viable, attractive, ‘clean’ energy source, helping to preserve our planet for posterity - since as in John Audubon’s words, “...the world is not given by our fathers, but borrowed from our children.”