| Wind energy is an environmentally inert, clean, and | | | | systems, these smaller turbines are also being used in |
| inexhaustible source of electric power that, as it turns | | | | combination with solar (photovoltaic) systems, |
| out, is really just another form of solar energy. The sun | | | | rechargeable deep-cycle batteries, and diesel |
| creates wind by its uneven heating of the planets | | | | generators to provide storable, on-demand power in |
| atmosphere. Its moderated by the earths rotation and | | | | more remote, off-the-grid places. |
| irregularities in its surface. The planets terrain, water | | | | In most residential situations, a wind turbine is used as a |
| bodies, and vegetation then affect the wind flow | | | | supplemental source of power in combination with |
| patterns. With the invention of wind turbines, we can | | | | local, on-the-grid, utility power. There is something called |
| now harness the winds energy and use it instead of | | | | a cut-in speed (7-10 miles per hour), below which the |
| purchasing electricity from the utility companies that | | | | wind turbine will cease to provide an output, and the |
| are derived from non-renewable sources. | | | | utility grid provides the structures power. Above the |
| The easiest way to understand how wind turbines | | | | cut-in speed, the wind turbine kicks in and the grid |
| work is to think of a fan operating in reverse rather | | | | power supply is proportionately reduced (depending on |
| than electricity spinning the blades and thus generating | | | | the structures energy draw at the given moment). |
| wind, the wind spins the blades, thereby generating | | | | If the output produced by the wind turbine exceeds the |
| electricity. | | | | draw from the structure (and/or storage devices, like |
| Breaking it down to its simplest components, a wind | | | | batteries), the excess power is then sold back to the |
| turbine operates as follows:the wind turns the | | | | pubic utility company. Use of wind energy can reduce |
| bladesthe blades spin a shaftthe shaft connects to a | | | | a residences energy costs by, on average, 50-90%, |
| generatorthe generator produces electricity | | | | though these numbers are influenced by a variety of |
| To expand on that simplification, the turbines blades | | | | factors and, as such, can fluctuate greatly. |
| are connected to a hub thats mounted atop a turning | | | | In a typical residence that uses under 10,000 kilowatt |
| shaft which runs into a gear transmission box that | | | | hours per year of electric power, a 5-15 kilowatt wind |
| increases the turning speed which, in turn, is connected | | | | turbine should more than suffice. This type of system |
| to a high speed shaft that cranks the generator. If the | | | | can run anywhere from $6,000-$22,000 to install, |
| wind speeds get too high, a brake is deployed to slow | | | | depending on a variety of factors, including: its size, |
| the blades down and prevent damage being done to | | | | your intended application, and any service contracts |
| the system. | | | | entered into with the manufacturer. |
| There are two basic types of wind turbine:horizontal | | | | Being that certain situations (such as in the city) make |
| axis wind turbines: the kind most commonly in use | | | | personal wind power use an unviable option, a general |
| today and the focus of U.S. | | | | rule of thumb is to consider installing your own wind |
| Department of Energy research on wind power, these | | | | power system if and only if you pay at least 10 cents |
| come in two varieties | | | | per kilowatt hour and your locations average wind |
| 2-blade horizontal axis turbines spin downwind | | | | speeds exceed 10 miles per hour. |
| 3-blade horizontal axis turbines spin upwindvertical axis | | | | The larger wind turbines have capacities upwards of |
| wind turbines | | | | 50 kilowatts, running these days into the |
| The size of a wind turbine will influence its power | | | | several-megawatt range. These windmills, known as |
| generating capacity, with the smaller windmills that | | | | utility scale turbines, can be grouped together and |
| produce under 50 kilowatts being the type most | | | | connected to central lines for transmitting and |
| commonly used to power water pumps, telecom | | | | distributing in bulk to the local utility grids that, in turn, sell |
| dishes, and homes. | | | | that power to homes and businesses across the land. |
| In an innovative advancement known as hybrid wind | | | | These are called wind power plants or wind farms. |