Introduction:Alternative energy is power that comes from renewable energy sources or sources that will not run out, and do not produce large amounts of pollutants. CITATION Placeholder1 \l 3081 (The Electricity Forum, 2014) Sustainable energy and its importance globally has been growing steadily as the world’s population increases and the ever increasing need for electricity grows. Sustainable energy is important for many other reasons as well as being a sustainable supply of electricity for larger populations globally. It provides clean energy, it has many environmental benefits and provides many job opening and contributes to a stronger economy. All these reasons help show how important renewable energy is, not only for the future, but for now. CITATION Ren14 \l 3081 (Renewable Energy World, 2014) All throughout history wind has been used and harnessed as a source of power from windmill to pump water or grind corn, to sails to propel ships. Since then they have slowly been developed to the point that they are at today. CITATION Win13 \l 3081 (Wind energy foundation, 2013) Wind turbines today are now at the point where a single wind turbine can produce enough power for 600 households. CITATION Chr11 \l 3081 (Curtis, 2011) There are many different designs of wind turbines that are capable or large scale power production, but research carried out by engineers and scientists have shown that a 3-bladed, horizontal axis wind turbine is the best design for industrial-scale needs. However, scientists are constantly facing difficulties in terms of changing the designs in order for them to produce more power, to be more cost effective and more reliable. CITATION Kid14 \l 3081 (KidWind Project Inc., 2014)
Energy is produced by wind energy, in the form of kinetic energy, turning the turbine blades around the motor. The motor is connected to the main shaft which turns inside the generator housing. Here, a magnetic rotor spins inside copper wired which in turn allows the electricity to flow thus producing electricity. CITATION Fou14 \l 3081 (Foundation for Water and Energy Education, 2014)
There are several factors that affect the efficiency of the energy production in a wind turbine. If there is not a sufficient amount of wind, there will not be enough power to spin the turbine, which means that no energy will be produced. This can be shown by the equation P=kVF, where P is wind power, V is wind speed and F is wind force. Places of higher altitudes also have higher wind speeds and less obstructions, this all leads to more energy and power production. The shape of the blades also plays a large role in the amount of power and energy produced. The amount of lift given off depends largely on the angle of the blade. If the angle of the blade is too large the amount of resistance is increased which causes more drag. And lastly, the air temperature surrounding the turbines. Colder air is a lot denser that warmer air, this means that the colder the air the more power output. CITATION Win11 \l 3081 (WindTurbines.net, 2011) The cost of purchasing and installing a wind turbine varies depending on the size and power output capacity. But the cost for the most common wind turbines installed today range from $3-4 million for one turbine. CITATION Win14 \l 3081
