By Emily Claps, Danny Tobin, and Jonah Bader
Every hour, Earth receives enough energy from the Sun to meet humanity’s entire global energy demand for a year. In 18 days, the sunlight that hits Earth’s surface carries as much energy as all of the coal, oil, and natural gas that remains on the planet. In other words, there is no shortage of solar energy—the challenge is capturing it.
Due to a host of factors, ranging from the Earth’s reflectivity to the limitations of technology, it is unlikely we will ever come close to harnessing all of that energy. Yet the amount of incoming solar radiation is so staggering that we just need to capture a tiny portion of it to bring us well on our way to a carbon-free future.
With advances in solar technology over the last decade, prices have plummeted and people all over the world are tapping into this underutilized power source. But how does the technology work?
Solar panels consist of a set of photovoltaic (PV) cells, which are essentially a sandwich of two oppositely charged slices of a semiconductor (a material whose ability to conduct electricity varies with conditions), such as silicon. An incoming photon (a particle of light) knocks electrons free from the atoms on the negative slice. Since electrons are negatively charged, they are driven to flow towards the positive side. By directing those electrons to flow through a wire, however, we create an electric current that can be used to power any appliance or electronic device.
Basic schematic of a photovoltaic solar panel.
As long as the Sun keeps shining, it serves as a virtually unlimited energy source. This is why solar power is considered a form of “renewable energy” or “sustainable energy”. Solar power is also a form of “clean energy” or “green energy” because the panels produce no greenhouse gas emissions, or emissions of any kind, in the process of generating electricity. (The only emissions associated with solar power come during the manufacturing, installation, and disposal phases of the panels’ life cycle.)
The Sun makes life possible for almost every organism on Earth, and with solar power, it’s also our lifeline to a better life and a safer future. Learn more about how you can go solar with Solstice.