Previous Year Question

Moving air possesses Kinetic Energy because of its motion. The blades of a wind turbine capture this kinetic energy and begin to rotate.

The rotation of the blades first produces mechanical rotational energy. This rotation is transmitted through the shaft to a generator, where mechanical energy is converted into electrical energy.

Thus, the basic energy conversion can be understood as—

Kinetic Energy of Wind → Mechanical Energy → Electrical Energy

The simplified expression for power available in wind is—

where is the density of air, is the area swept by the turbine blades and is wind speed. This also shows why available wind power increases very rapidly with wind speed, since power is proportional to .

Potential Energy is not the primary energy captured by a wind turbine. Solar Energy indirectly drives atmospheric circulation and the formation of winds, but the turbine directly captures the Kinetic Energy of moving air.