Wind Power Physics

A Wind Power Turbine
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Comparing Alternative Energy Forms

The Physics of Wind Power

Forces play a part of every action that occurs anywhere at any time. Force is the foundation that the technology of both wind power and hydroelectric power utilize. Wind power harnesses the forces in the horizontal direction of motion, while hydroelectric power derives energy from the vertical direction of motion. But of course wind does not operate only in the horizontal direction. One definte hindrance of wind power is that the blades must turn along only one axis. This page will analyze the forces that act in the horizontal direction of motion, and will for the most part neglect vertical force vectors. If any of the terminology so far presented is unclear, please read the help guide at the link for Forces & Vectors. It is also important to understand the parts of a wind tower. Please read up on the parts and what they do at the Wind system web page.

The following diagram illustrates the forces that are important when analyzing the physics of wind power. Because the wind must physically push the blades of the wind tower, the wind force must overcome the weight of the blades. If the force of the wind is not enough to spin the blades, then a wind tower will obviously not produce energy. Although making the blades of a wind power lighter, a reduction in weight will often mean the blade is less strongly connected to the turbine. As sythetic materials become stronger and more flexible, the weight of the blades will decrease while not sacrificing safety and reliability.The force vectors for the weight of the blades are drawn in the next diagram downward:

Wind Forces Diagram

Wind power is optimized in locations where wind is strong. The wind speed is defined as the distance that wind travels divided by the amount of time that it takes the wind to travel that distance. Several factors limit the amount of energy that can be harvested from wind. If you have already read the information about nuclear power physics, read on, because the same concepts are discussed here, but using vectors to represent the forces, work done, and motion that takes place.The next diagram shows that work is done in the direction of force, the wind doing work on the blades, that do work on the turbine, that then does work on the generator:

Wind Work Done Diagram

To test how much you understand of the physics of wind power, take this quiz.

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	The Physics of Wind Power Forces play a part of every action that occurs anywhere at any time. Force is the foundation that the technology of both wind power and hydroelectric power utilize. Wind power harnesses the forces in the horizontal direction of motion, while hydroelectric power derives energy from the vertical direction of motion. But of course wind does not operate only in the horizontal direction. One definte hindrance of wind power is that the blades must turn along only one axis. This page will analyze the forces that act in the horizontal direction of motion, and will for the most part neglect vertical force vectors. If any of the terminology so far presented is unclear, please read the help guide at the link for Forces & Vectors. It is also important to understand the parts of a wind tower. Please read up on the parts and what they do at the Wind system web page. The following diagram illustrates the forces that are important when analyzing the physics of wind power. Because the wind must physically push the blades of the wind tower, the wind force must overcome the weight of the blades. If the force of the wind is not enough to spin the blades, then a wind tower will obviously not produce energy. Although making the blades of a wind power lighter, a reduction in weight will often mean the blade is less strongly connected to the turbine. As sythetic materials become stronger and more flexible, the weight of the blades will decrease while not sacrificing safety and reliability.The force vectors for the weight of the blades are drawn in the next diagram downward: Wind power is optimized in locations where wind is strong. The wind speed is defined as the distance that wind travels divided by the amount of time that it takes the wind to travel that distance. Several factors limit the amount of energy that can be harvested from wind. If you have already read the information about nuclear power physics, read on, because the same concepts are discussed here, but using vectors to represent the forces, work done, and motion that takes place.The next diagram shows that work is done in the direction of force, the wind doing work on the blades, that do work on the turbine, that then does work on the generator: To test how much you understand of the physics of wind power, take this quiz.