Sources of Energy
1. A windmill is a simple machine that works with the energy of the wind. The windmill can be used to run a pump to draw water from the ground. It can also be used to run a flour mill to grind grain.
2. The moving water also possesses kinetic energy. The water – wheel is a device used for obtaining energy from flowing water.
3. The energy of naturally flowing water in high rivers is generally stored behind dams as potential energy and then further used to generate electricity. The electricity produced by using the energy of flowing water is known as hydro – electric power. The most important advantage of water energy is that like wind energy, it does not cause
any pollution.