California Poppies, Sandwiches, and Solar Panels

[Originally published April 2, 2015]

California’s state flower, the California Poppy, aka Eschscholzia californica, is the perfect representative of our Golden State. It opens its petals to sunshine, closes them at night and on cloudy days. Sounds a lot like a solar energy, n’est-ce pas?

Equally enchanting is the photovoltaic cell. Photovoltaic meanschanging light into energy. (tweet this!) And when you link a lot of photovoltaic cells together, you’ve got a solar panel.

"Each photovoltaic cell is basically a sandwich made up of two slices of semiconducting material, usually silicon—the same stuff used in microelectronics.”


Phosphorus and boron are added to this silicon sandwich to create an electric field. These photovoltaic cells allow particles of light, photons, to knock electrons free of the atoms in order to generate electricity. When a photon of sunshine knocks an electron free of its atom, the electric field created expels the electron out of the silicon junction. (All made possible by the application of Einstein’s Nobel Prize winning work on the photoelectric effect.) Metal conductive plates along the sides of this tiny energy-sandwich then collect the electrons and transfer them to the wires. Sun-generated electricity!

For a more detailed explanation of how solar panels work, check out How Do Solar Panels Work? at