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What are solar shingles?

Solar Shingles 101

Solar shingles have a special property that allows them to make electricity from sunlight. Let’s break down the scientific process behind how this works.

A photon is a unit of electromagnetic radiation with no charge; Its protons (positively charged subatomic particles) and electrons (negatively charged subatomic particles) are equal, giving it no charge. The photon, here, is a particle of sunlight. Sunlight strikes a solar shingle coated with a special surface that naturally knocks off an electron from the particle of light. The freed electron travels through an electrical circuit to an area where other electrons are stored. This collection of electrons is then harvested to generate a current. This is how all solar electricity works, whether it's a solar shingle, solar panel or something else. Photovoltaic (PV) devices like these can be used to power anything from a calculator to a skyscraper.

Solar shingles, in theory, can produce 100 percent of a building's electricity usage, but it depends on a number of factors: the demand of a building, the amount of sunlight the structure gets at that particular geographic location, the building's current utility rates and availability of sufficient space on the roof that opens to southern skies.

Solar shingles can work practically anywhere (even in gray-weather places) because they can use diffused, scattered sunshine on overcast or even rainy days. In fact, the country with the most buildings that use PV devices is Germany, and the American Solar Energy Society (ASES) says that all 50 states in the US get better sunlight than Germany.

But what if you live in a sunny place where there is ample sunlight year round? Can your solar shingles produce too much power? Yes, and this is good news. When this happens, your excess energy is sent to the electric grid, and you usually receive a check from the electric company or a credit on your next utility bill. Jurisdictions differ in how they address excess energy, so check with your electric company to find out how this process works in your area.