Wind turbines convert the wind's kinetic energy into mechanical energy to produce electricity. Gravity and electromagnetic forces use the radiant light and heat from the sun. The sun is the source of all fossil fuels and renewable energy. Approximately 2 percent of the sun's energy is converted into wind energy and a significant part of it is transformed into biomass energy by plants.
When wind blows past a structure or an obstacle, it exerts pressure/force against it. The movement of the obstacle against the wind transforms the wind energy into mechanical energy. In line with this principle, the force of the wind can turn a propeller or a drum around a mill. Today, we have wind turbines that use wind motion to convert its force into mechanical energy.
The amount of energy carried by the wind to the turbine depends on the following factors:
- Wing surface area
- Air density
- Wind speed
These factors determine the capacity of the wind turbine. Wind farms are made up of wind turbines. Wind turbines are the most modern generation of wind energy conversion systems. Wind farms mostly use horizontal axis turbines.
Wind energy is actually a byproduct of the sun. Sunlight starts heating the cool air over the land. As you can remember from physics lessons, warm air expands and rises up while cold air condenses and sinks, resulting in the flow of air, forming wind.