How do we turn energy from the sun, wind and water into clean electricity to power our homes? Wind turbine blades rotate when hit by the wind. A generator built into the nacelle then converts the kinetic energy of the turning shaft into electrical energy. This then passes through a transformer, which steps up the voltage so it can be transported on the National Grid or used by a local site. F rom micro-turbines for an individual house right up to enormous, off-shore windfarms, all wind turbines use the same mechanics to generate electricity.
Most onshore wind turbines have a capacity of megawatts MW , which can produce over 6 million kilowatt hours kwh of electricity every year. To see how a wind turbine works, click on the image for a demonstration. Wind flow patterns and speeds vary greatly across the United States and are modified by bodies of water, vegetation, and differences in terrain. Humans use this wind flow, or motion energy, for many purposes: sailing, flying a kite, and even generating electricity.
The terms "wind energy" and "wind power" both describe the process by which the wind is used to generate mechanical power or electricity. This mechanical power can be used for specific tasks such as grinding grain or pumping water or a generator can convert this mechanical power into electricity. 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. This translation of aerodynamic force to rotation of a generator creates electricity. Most commonly, they have three blades and operate "upwind," with the turbine pivoting at the top of the tower so the blades face into the wind.
Vertical-axis wind turbines come in several varieties, including the eggbeater-style Darrieus model, named after its French inventor. Wind turbines can be built on land or offshore in large bodies of water like oceans and lakes.
The U. Department of Energy is currently funding projects to facilitate offshore wind deployment in U. Wind farms can be positioned either on land or offshore. Wind speeds at sea are significantly higher, making offshore wind farms more efficient than their landlocked counterparts. However, the logistics of building offshore wind farms and transporting electricity from them have been challenging. The main application of modern wind farms is to generate usable electricity for a regional power grid.
The size, design, and rotor diameter of a wind turbine will determine how much power it can generate. Turbines have a designated rated capacity, based on how much power they can produce under optimal wind conditions. For example, a 2 kW turbine will produce 2 kWh of electricity per hour.
A typical turbine is designed to function best at wind speeds of around 11 — 15 meters per second. A wind farm is simply a collection of wind turbines placed in a strategic place to capture the most wind energy. Generally, this will be out at sea, high up on a hill or mountainside, or on a flat open plain.
A wind farm can be just a few turbines, or a few hundred. It just depends on the facility. As wind turbine technology is continuously refined and improved, and more wind farms are constructed, wind power is expected to grow in importance. This clean, environmentally friendly source of energy remains one of the most important alternatives to fossil fuels. Wind energy can be used to power a single property, such as a home or business that is too far away from the national grid to be connected, or generate power for the national power grid that supplies us all with electricity.
Wind energy is produced by the use of wind turbines. How do wind turbines work? Whether on a small or large scale, they use their blades to capture the kinetic energy of the wind to make them spin. On a small scale, wind turbines can power a single property, but on a large scale, they contribute their electricity to the power grid. The best thing is, wind turbine technology is getting better all the time, so things will only become more efficient from here.
Renewable Energy Certificates RECs are tradable, non-tangible energy commodities that demonstrate 1 megawatt-hour MWh of energy was produced from a wind farm. The more RECs that are purchased, the more valuable clean energy generation becomes, leading to more production and more renewable energy on the grid.
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