Question

What are solar cells? What are they made up of? How are they useful?

Answer 1

Solar Cell: Device converting solar radiation into electricity.
They are made up of crystalline Silicon
Solar power is amazing. On average, every square meter of Earth's surface receives 164 watts of solar energy. In other words, you could stand a really powerful (150 watt) table lamp on every square meter of Earth's surface and light up the whole planet with the Sun's energy! Or, to put it another way, if we covered just one percent of the Sahara desert with solar panels, we could generate enough electricity to power the whole world. That's the good thing about solar power: there's an awful lot of it—much more than we could ever use.