Solar Energy Basics (Text Version)
This is the text version of the video "Solar Energy Basics."
The History of Solar Power
Voice Over: Solar energy is the most abundant source of energy on Earth, fueling the plants we use for food and fuel and powering the wind and weather in our skies.
Humans first directly harnessed solar power in the 7th century B.C., when a magnifying glass was used to concentrate the sun's rays to make fire.
The first solar device to produce electricity from sunlight was installed on a rooftop in New York in 1883 by American inventor Charles Fritts.
In 1905, Albert Einstein discovered light particles known today as "photons." He predicted that photons above a certain energy level would eject electrons. This revolutionary discovery led to our modern semiconductor technologies, including solar cells. And it also earned Einstein a Nobel Prize in physics.
In 1954, scientists at Bell Labs created the modern solar-electric cell, partly by accident, while researching the properties of silicon semiconductors. They found that when certain impurities were added to silicon, it generated a strong electric current when exposed to light.
At first, solar panels were only used to power remote pieces of electrical equipment—like rural telephone lines—and satellites in space. In fact, Vanguard 1—the first satellite with solar cells—was launched in 1958 and (though it's stopped working) remains the oldest artificial satellite in orbit today, logging more than 6 billion miles.
By the end of the 20th century, engineering improvements had made solar cells cheaper and easier to make. They began to appear on rooftops and in large solar farms to generate electricity for regular use.
Today, solar energy is one of the fastest growing sources of our electricity. And new improvements are making solar cells even lighter, cheaper, more powerful, and more flexible, so we can use them in more places.