Fun Facts

Wind Dynamics

When cool air fills the void left behind from hot air rising, we get wind and If you place an object like a boat’s sail in the path of that wind, the wind will push on it, transferring some of its own energy of motion to the sail, causing the boat to move. The same thing happens with the blades on a windmill.

Windmill Kahuna

How big are wind turbines? Wind turbines are available in a variety of sizes and therefore power ratings. The largest machine, such as one built in Hawaii, has propellers that span more than the length of a football field and stands 20 building stories high and produces enough electricity to power 1400 homes. A small home-sized wind machine has rotors between 1 and 8 meters in diameter and stands upwards of 10 meters and can supply the power needs of an all-electric home or small business.

Wind Power

The wind is free and with modern technology, it can be captured efficiently. Once a wind turbine is built, the energy it produces does not cause greenhouse gases or other pollutants.

At this location, we’ll be looking at the wonders of wind power!

Wind Power Clean Renewable Energy

Why wind?

The two biggest reasons for using wind to generate electricity are the most obvious ones: wind power is clean and it's renewable. It doesn't release harmful gases like CO2 and nitrogen oxide into the atmosphere the way coal does and we are in no danger of running out of wind anytime soon.

It's hard sometimes to imagine air as a fluid. It just seems so ... invisible. Air is a fluid like any other except that it’s particles are in gas form instead of liquid. When air moves quickly, in the form of wind, those particles are moving quickly. Motion means kinetic energy, which can be captured. At its essence, generating electricity from the wind is all about transferring energy from one medium to another.

Wind power all starts with the Sun.When the Sun heats up a certain area of land, the air around that land mass absorbs some of that heat. At a certain temperature, that hotter air begins to rise very quickly because a given volume of hot air is lighter than an equal volume of cooler air. When that lighter hot air suddenly rises, cooler air flows quickly in to fill the gap the hot air leaves behind. That air rushing in to fill the gap is wind.

Wind flow is also modified by the Earth's terrain, bodies of water and vegetative cover. This wind flow, or motion energy, when harvested by modern wind turbines can be used to generate electricity.

Nation Building

In the United States, millions of windmills were erected as the American West was developed during the late 19th century. Most of them were used to pump water for farms and ranches. By 1900, small electric wind systems were developed to generate direct current but most of these units fell into disuse as inexpensive grid power was extended to rural areas during the 1930’s. By 1910, wind turbine generators were producing electricity in many European countries.

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Windmill Construction

The simplest possible wind-energy turbine consists of three crucial parts. The rotor blades are basically the sails of the system. When the wind forces the blades to move, it has transferred some of its energy to the rotor. The wind-turbine shaft connects to the center of the rotor. When the rotor spins, the shaft spins too. The rotor has transferred its mechanical, rotational energy to the shaft, which enters an electrical generator on the other end.

Wind turbines convert the kinetic energy in the wind into mechanical power.This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or the power can be converted to electricity, stored in batteries and used to power homes. See below.

The Generator

The above generator consists of magnets and a conductor. The conductor is typically a coiled wire. Inside the generator, the shaft connects to an assembly of permanent magnets that surrounds the coil of wire. When the rotor spins the shaft, the shaft spins the assembly of magnets, generating voltage in the coil of wire. That voltage drives electrical current (typically alternating current, or AC power) out through power lines for distribution.

Fun Facts

Wind Dynamics

When cool air fills the void left behind from hot air rising, we get wind and If you place an object like a boat’s sail in the path of that wind, the wind will push on it, transferring some of its own energy of motion to the sail, causing the boat to move. The same thing happens with the blades on a windmill.

Windmill Kahuna

How big are wind turbines? Wind turbines are available in a variety of sizes and therefore power ratings. The largest machine, such as one built in Hawaii, has propellers that span more than the length of a football field and stands 20 building stories high and produces enough electricity to power 1400 homes. A small home-sized wind machine has rotors between 1 and 8 meters in diameter and stands upwards of 10 meters and can supply the power needs of an all-electric home or small business.

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