How solar power went from satellites to your back yard [Video]

Solar panels are rapidly becoming a common sight on homes, but once upon a time they were little more than a rare curiosity. How did we get from using solar energy on satellites to it becoming the most affordable source of electricity? Is there anything about its historical trajectory that might suggest where it’s headed next?

To dig into these juicy questions, we spoke with the guy who wrote the book on solar power’s history, John Perlin. The history he took us through had some unexpected twists.

How do solar panels even work?

Let’s start with the basics of photovoltaics. Trust me, this is helpful context for explaining how the technology evolved over time.

Fundamentally, electricity is the flow of electrons. Some molecules are missing electrons compared to their stable state. Other molecules have too many electrons. With enough energy, electrons can hop off a molecule with too many and onto another with too few. That movement of electrons can become an …