PV Gap

Suzanne Said:

Will a solar powered lightbulb power itself?

We Answered:

Nice idea, but it violates the laws of physics. It might return a very tiny fraction of its energy to the solar panel, but the light is likely a lot less intense than sunlight, and isn't just focused on the solar panel. In fact, the light from the bulb might not be bright enough to return any energy to the system at all. At best, your light bulb might stay lit a fraction of a second longer than it would otherwise. Also, energy is lost from various parts of the system along the way.