This is the kind of energy most people think of when you mention ‘alternative energy’, and for good reason! Without the sun, none of anything you see around you could be here. Plants have known forever how to take the energy and turn it into usable stuff… so why can’t we?
This solar cell is a real battery, and you’ll find that even in a dark room, you’ll be able to measure a tiny amount of current. However, even in bright sunlight, you’d need 80 million of these to light a regular incandescent bulb.