Wind energy has been used for centuries, to pump water from wells, set sail on the sea, and more recently to create renewable electricity. Wind turbines are large structures, with three blades and a generator that produces electricity as the blades spin. The mechanical structure of the turbine is the three blades attached to a rotor, which has a main shaft that connects to the generator. The generator is located at the top of the wind turbine to gain the most power. This is the process of converting kinetic energy to electricity. In addition to wind turbines with blades there are also vertical-axis structures that are oval shaped.  The structure can be as tall as 20 stories with turbine blades that stretch 200 feet. The largest producers of wind energy include Germany, Spain, and The United States. 
A wind turbine is most effective when the wind speed is above 12 miles per hour. This is because the wind must be strong enough to turn the turbine blades so that they have enough energy to produce electricity. Each turbine is capable of producing 50-300 kilowatts of electrical current.  The wind energy necessary for wind turbines to function is a product of solar energy. This is because the wind is produced when sunlight unevenly strikes the air in the atmosphere while also being altered by the Earth’s rotation, landscape and biosphere. 
The National Renewable Energy Laboratory organization (NREL) thoroughly researches, analyzes, and inspects the wind turbines they produce to ensure the fullest capability, production, and safety. The NREL has detailed analysis and information about the capabilities, facilities involved in production, and projects regarding wind turbines and wind energy. There is research and analysis focusing on large scale wind farms, off-shore and single, smaller turbines, as well as the function of the power grid and how to accelerate interest in the energy source.
Every state in America has wind turbines or wind related energy programs. California has the largest amount of turbines in the country with over 11,000 structures.  The state has windy seasons and therefore has created many wind farms, which consist of thousands of turbines. California’s wind farms generate 11% of the worlds total energy produced by wind power.  Wind turbines can produce useful energy as a single structure or within a wind farm connected to a large power grid. In some cases wind energy is linked to a photovoltaic cells set up for optimal clean energy production.  Just as someone is able to use solar energy and solar modules to lower their energy expenses, they can also implement wind turbines onto their home or business.
The cost of wind energy has declined 85% in the last couple of years making it more affordable to create wind farms. This industry has created jobs for thousands of Americans and promotes economic progress. This technology is so effective that wind farms in certain areas are able to reimburse themselves for the cost of construction within as little as three months. 
Wind energy is also a desired energy source because it is completely renewable and clean energy. This is an important factor in industry due to the dangers of climate change. Wind energy does not consume water like other energy sources that are greatly depleting the Earth’s fresh water resources. According to the National Resource Defense Council (NRDC) there are improvements being made to maximize the effectiveness of wind energy. These include building taller turbines, building in landscapes originally not utilized, and using stronger rotors, which connect the movement of the blades to the generator. This effective and clean technology is supported by governments and has been the subject of new policies promoting the expanse of wind energy.