Question

A certain form of energy which is not sourced directly or indirectly from the sun and does not cause any pollution is very easily converted into electricity. This form of energy is, however, not available everywhere. Moreover, it is technically very difficult and expensive to obtain it. Name the form of energy.

Answer 1

It is geothermal energy, which is not derived directly or indirectly from the sun and does not cause any pollution. It can be  converted into electricity. Also, geothermal energy is not available everywhere and is very difficult and expensive to obtain.