How Solar Panels Work
Since solar energy is one of the cleanest ways to produce electricity and is the quintessential renewable energy (unlike fossil fuels, sunlight won’t be in short supply any time soon), it’s important to get the facts straight about how solar panels work.1
Solar panels are made up of many smaller components called photovoltaic (PV) cells. PV cells operate on a principle called the photoelectric effect, which occurs when a material produces a small amount of electricity when exposed to light. You see the photoelectric effect in action whenever light hits a piece of metal—the metal sparkles and shines because the electrons in the metal’s atoms absorb the energy in the light and begin to move around. When these electrons move around, some of them get knocked off their atoms, which generates a very small amount of electricity.2
PV cells take advantage of the photoelectric effect to produce electricity, though the way they do that is a bit more complicated than the example I just described.
PV cells are made up of two layers of silicon. One layer is positively charged, the other negatively charged. When sunlight hits the positively charged layer, the photoelectric effect gets the silicon electrons so excited that they jump from the positive layer to the negative one, which creates an electric current (electron, electricity—get it?).²
Solar panels have applications beyond solar panel farms. For example, solar panels can power a farm’s weather station³ or can be used to generate electricity for a home water heater.4
According to the US Department of Energy, “PV panels on just 0.6% of the nation’s total land area could supply enough electricity to power the entire United States.”1 Solar power is growing quickly in the U.S. and the cost of manufacturing PV cells has dropped significantly in recent years.1 As the push for renewable energy increases, we can expect to see more solar panels in the future.
- “Solar Energy in the United States,” US Department of Energy, n.d., http://energy.gov/eere/solarpoweringamerica/solar-energy-united-states
- Gil Knier, “How Do Photovoltaics Work?” NASA, 2002, http://science.nasa.gov/science-news/science-at-nasa/2002/solarcells/
- Clyde W. Fraisse, George W. Braun, William R. Lusher, and Lee R. Staudt, Your Farm Weather Station: Installation and Maintenance Guidelines, AE502, Gainesville: University of Florida Institute of Food and Agricultural Sciences, 2015, http://edis.ifas.ufl.edu/ae502
- Nicholas W. Taylor, M. Jennison Kipp, and Kathleen C. Ruppert, Energy Efficient Homes: Incentive Programs for Energy Efficiency, FCS3268, Gainesville: University of Florida Institute of Food and Agricultural Sciences, 2012, https://edis.ifas.ufl.edu/fy1033
Photo credits: UF/IFAS