Wind Energy Basics       

Air in motion is wind. Wind energy is a result of the uneven heating of the earth from solar energy. As the air gets heated, it gets lighter and rises. As the air rises, cooler air rushes in to replace the heated air, thus causing wind. Solid land masses heat faster than water masses which causes a constant wind near beaches and shorelines. The force of the wind is used to spin propellers which in turn spin generators which in turn makes electricity. In engineering terms, the kinetic energy of wind is converted to mechanical energy which is converted to (typically) electrical energy.

Capturing the Wind Energy

Anywhere there is a consistent wind can be considered as a wind energy source. Consistant means wind blows there more often than not. Wind turbines are most often recognized as horizontal-axis machines (propeller type turbines) but can also be vertical-axis machines (egg-beater type turbines). The first job of a wind turbine is to convert the kinetic energy of the wind into mechanical power, normally a turning shaft to a generator. The generator converts this mechanical power into electricity which can be stored in batteries or used on site. Turbine sizes range from residential applications to utility production applications. On this site we will discuss residential applications in most instances.

How Do I Know How Much Wind is Available?

How much wind you receive at your location depends on local wind flow patterns. These patterns are influenced by Earth's surface irregularities (mountains, plains, etc.), bodies of water and vegative cover. Wind speed is the most important element in projecting turbine performance. Typically, an annual average wind speed between 7 and 10 MPH is required for small wind electric turbines. For years wind data has been collected which allows you to predict how much wind is available in your area of the country. There are a number of sources available to determine the available wind energy which will be discussed later.

Wind Energy Costs

Just as with solar costs, the cost of wind power is steadily decreasing. You can buy a turbine for less than $1,000 and do the construction yourself to save a considerable amount of money or hire a local professional to do the work for you. Note that systems constructed by do-it-yourselfers can be extremely cost effective.