In the 19th century, it was observed that the sunlight striking certain materials generated detectable electric current called the photoelectric effect. It was this discovery that laid the foundation of solar cells and then the invention of solar panels.

The first commercial solar panel was created by an American inventor and engineer, Charles Fritts (1850-1903) in 1883. A year later, using Fritts’ selenium cells, the first rooftop solar array (partial assembly encompassing the solar panel, the photovoltaic system or PV system, but not the balance of the system) was installed on a New York City rooftop in the state of New York in the United States.

To accomplish this, Fritts coated the semiconductor material selenium with an extremely thin layer of gold. The resulting cells had a conversion electrical efficiency of only about 1% owing to the properties of selenium, which in combination with the material’s high cost, prohibited the use of such cells for energy supply.

A solar cell is an electrical device that converts the energy of light directly into electricity by the photovoltaic effects which is a physical and chemical phenomenon.

The many applications for solar panels include their use in agriculture as a power source for irrigation. In health care panels can be used to refrigerate medical supplies.

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