WIND TURBINES
A wind turbine is the modern version of a windmill simply it is a machine that uses wind power to generate electricity, their purpose is to reduce reliance on fossil fuels to create energy, besides, to create energy in a less wasteful manner.
Wind turbines work on a simple principle they use the kinetic energy from the wind to generate electricity. It works when the wind pushes the blades of the wind turbine spins a motor to generate electrical power that is ready for consumer use.
WHAT IS A WIND FARM?
Wind farms are the areas where many large wind turbines are grouped. To “harvest” the wind power. Large wind farms could have hundreds of wind turbines spread out over hundreds of kilometers. In wind farms, the land between turbines could be used for other purposes, such as regular farming. Wind farms are placed inconsistent and less turbulent airflow areas. They may be land-based (onshore) or out at sea (offshore), either on platforms or on pillars coming from the sea bed.
WIND TURBINE TYPES
Horizontal Axis Wind Turbine (HAWT)
HWAT is the most common wind turbine design in use today due to its strength and efficiency. These turbines can have two, but more often three, blades on top of a tower reaching up to 120m tall. With the blades of the turbine being perpendicular to the wind, the rotation of the blades can generate more power compared to the vertical axis wind turbine.
Vertical Axis Wind Turbine (VAWT)
A “VAWT” is a Vertical Access Wind Turbine that has blades attached to the top and the bottom of a vertical rotor, this type is less affected by frequent wind direction changes as compared to HAWT due to the blades being rotated on the rotor shaft perpendicular to the ground. Very few vertical-axis wind turbines are in use today because they do not perform as well as horizontal-axis turbines.
HOW DO WIND TURBINES WORK?
A wind turbine turns wind energy into electricity using the aerodynamic force from the rotor blades, which work like an airplane wing or helicopter rotor blade. When wind flows across the blade, the air pressure on one side of the blade decreases. The difference in air pressure across the two sides of the blade creates both lift and drag. The force of the lift is stronger than the drag and this causes the rotor to spin. The rotor connects to the generator, either directly (if it’s a direct drive turbine) or through a shaft and a series of gears (a gearbox) that speed up the rotation and allow for a physically smaller generator. This translation of aerodynamic force to the rotation of a generator creates electricity.