Quick Facts About Solar

—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.

- They began to appear on rooftops and in large solar farms to generate electricity for regular use.

And new improvements are making solar cells even lighter, cheaper, more powerful, and more flexible, so we can use them in more places.

This milestone comes just three years after the industry completed its 1 millionth installation, a feat that took 40 years to accomplish. Most notably, the industry is projected to hit 4 million installations in 2023, illustrating solar’s rapid pace as the fastest-growing energy resource in the world.