How Do Solar Panels Work?

Solar panel basics
The Sun – that massive nuclear power plant in the sky – bathes Earth in enough energy to fulfill all the world’s power needs many times over. All life on earth gets its energy from the Sun; even the coal and oil burned today produces power by releasing the stored solar energy from hundreds of millions of years ago, thus the name “fossil fuels.”

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All light, including sunlight, contains energy. Usually when light hits an object, the energy turns into heat, but when light hits certain materials, like a solar panel, the energy instead turns into an electrical current, which we can then harness for power.

Solar photovoltaic (PV) panels use silicon crystals, which produce an electrical current when struck by light. While silicon is very efficient at turning light energy into electricity, it tends to cost more than “thin film” PV panels. These thin film panels use newer materials that produce smaller, more cost effective crystals, from materials such as copper-indium-gallium-selenide. Thin film solar utilizes stacked semiconductors only a few micrometers thick and has a variety of innovative applications such as roof shingles or solar window tinting that generate electricity, however they are usually less efficient than traditional silicon solar panels.

How does a solar panel turn sunlight into electricity?

In a crystal, the bonds (between silicon atoms) are made of electrons that are shared between all atoms of the crystal. Light gets absorbed, and individual electrons in bonds get excited into a higher energy level and can move around more freely than when it was bound. That electron can then move around the crystal freely, which produces an electrical current.

Bright future for solar power

It is very important that we continue to harness and increase our use of solar power (and other clean, renewable energies) especially as fossil fuels become depleted, more expensive, and fall out of favor with their consumers. Solar power is one of the safest, cleanest, and most reliable forms of producing electricity in the world today. As the global demand for energy grows and conventional energy resources become increasingly costly to extract, people are looking to the power of the Sun. In contrast to fossil fuels, the price of solar has fallen dramatically as its use has become ubiquitous. 

According to Swanson’s Law, when solar manufacturing capacity doubles, prices fall by 20%. Solar is no longer cost prohibitive; the price of producing electricity from solar panels has dropped from $74.67 per watt in 1976 to $0.74 per watt in 2013 with prices only continuing to drop due to better technology, a more mature industry, and more innovative financing plans.

Why solar panels?

Why is solar energy important to us? Every beam of light that we can convert into electricity is another step in reducing our dependence on polluting fossil fuels, and that’s one way we can help preserve our planet for ourselves and future generations. Deploying and installing solar panels is also a career field that cannot be outsourced, therefore by generating power from the Sun, we’re also generating jobs at home. If leaving a place better than you found it and creating good-paying jobs isn’t enough to motivate you, the fact that investing in alternative energy with Mosaic where investors can potentially earn competitive returns should also perk up some ears.