Why are windmills needed?

Answer 1

Windmills are needed usually to grind corn into wheat using wind-power. The main reason of using wind-power is because to grind corn needs a huge amount of energy and it would cost more to grind the corn into wheat than the actual price of the wheat. Nowadays windmills are not used and instead other ways are use to grind corn which are more power-efficient and therefore do not need much power and so can be powered from the grid