Voltaic means, “producing electric current.” The word comes from the name of Alessandro Volta, an Italian physicist who was a pioneer in the field of electricity during the 1700′s. (His name is also where the word “volt” comes from.)
Photovoltaic means, “creating electrical energy when exposed to light.”
A cell is a device that produces electricity. An example of an electrical cell is a flashlight battery.
Photovoltaic cells produce electricity when they are exposed to light. They usually consist of panels. The panels contain two layers of different materials.
When light hits these two layers, one of the layers becomes positively charged, and the other becomes negatively charged.
This works similarly to a regular flashlight battery, which has a positive end and a negative end. When a wire connects the two ends, they produce an electric current.
When the two layers of material in a solar cell are exposed to light, they create an electric current.
The AMOUNT of electricity generated by a solar power cell depends on several factors. Mainly:
- How big is the solar power device, and how much surface is exposed to the sun?
- How strong is the sun? (This depends on time of day, weather, latitude, etc.)
- How long is the solar power device exposed?
- How much impediment is there to the light? (Clouds, mist, dust, dirt, etc.)
In other words, a solar power cell generates electricity faster when the sun (or light) is brighter. A device with larger solar panels will produce more electricity than one with smaller panels. Exposing the cell for a longer period of time will create more electricity than exposing it for a shorter period of time. A panel near the equator will be more effective than one in an arctic region. A solar panel in misty or dusty conditions does not create as much electricity as it would in full, unobstructed sun.
Some solar cells produce only enough current to power small electronic devices, but can be “daisy-chained” (connected together) in order to create more electricity for other items.
Solar cells which produce enough electricity to run larger equipment (such as laptops) may be larger, more expensive, or heavier than the others.
But there are many varieties available. Individuals and companies are consistently striving to create lighter and more efficient portable solar cells.