With the world in desperate need of clean, renewable energy, that big, yellow ball in the sky seems to be a great solution. It’s estimated that 120,000 terawatts of power flow from the sun and through the earth every day — that’s 10,000 times more than flows through our entire industrial civilization at any given time, so we’d say transitioning to solar power is definitely a great idea. But, just how do solar panels work? Get ready for a quick and dirty lesson.
Solar energy systems work by allowing photons (particles of light) to knock electrons free from atoms, which generates a flow of electricity. The panels themselves are actually comprised of many photo-voltaic units (which is basically just a fancy word for a device that can convert sunlight into energy).
In order to function, photo-voltaic cells need to create an electric field: similar to magnetic fields, electric fields occur when opposite charges are separated. Each photo-voltaic cell is essentially a sandwich, except instead of bread there are two slices of semi-conducting material (like silicon). Solar panel manufacturers establish an electric field between the two slices by “doping” the silicon with other materials until each slice has a positive or negative electrical charge. Then, when a photon of sunlight knocks an electron free, the electric field will push that electron out of the silicon junction. Metal conductive plates on the sides of the cell collect these electrons and transfer them to wires, allowing them to flow like any other source of electricity.
When Science Shines Bright
As per the trend of the 21st Century, technology just keeps on getting better and better. Researchers have recently created ultra-thin, flexible solar cells that are about 1/100th the width of a human hair, and 20 times lighter than a sheet of office paper. They are light enough to sit on top of a soap bubble without popping it and are still capable of producing energy with as much efficiency as glass-based solar cells.
This development in solar energy systems could revolutionize day-to-day life by potentially allowing us to charge our phones while we’re walking down a sunny street, not to mention the impact it could have in architectural and aerospace projects.