“The Future of Alternative Energy Is Blowing your way” WIND ENERGY “The Future of Alternative Energy Is Blowing your way” By: Subrina Jones Chakar Thompson

OBJECTIVES Introduction to Wind Energy. To define the term Wind Energy. To label the parts of a wind turbine and briefly explain their roles. To explain how a wind turbine operates. To find out how wind energy is harnessed and converted. To determine the uses of Wind Energy. To outline the Disadvantages and Advantages of using Wind Turbines. Conclusion: Facts and Review.

INTRODUCTION TO WIND ENERGY-WHAT IS WIND? Wind is the movement of air from an area of high pressure to an area of low pressure. In fact, wind exists because the sun unevenly heats the surface of the Earth. As hot air rises, cooler air moves in to fill the void. As long as the sun shines, the wind will blow. And as long as the wind blows, people will harness it to power their lives.

INTRODUCTION TO WIND ENERGY Since early recorded history, people have utilized wind energy. It propelled boats along the Nile River as early as 5,000 B.C., and helped Persians pump water and grind grain between 500 and 900 B.C. As cultures harnessed the power that wind offered, the use of windmills spread from Persia to the surrounding areas in the Middle East, where windmills were used extensively in food production.

What is wind energy? Wind Energy is power that is created from air flow using wind mills, wind pumps, wind turbines or sails to produce : Mechanical or Electrical power .

Function of The parts of a wind turbine BLADES-Designed like airplane wings, modern wind turbine blades use lift to capture the wind's energy. Because of the blade's special shape, the wind creates a pocket of pressure as it passes behind the blade. ANGLE OF ATTACK

Function of The parts of a wind turbine (CON’T) NACELLE-The nacelle houses a generator and gearbox. The spinning blades are attached to the generator through a series of gears. The gears increase the rotational speed of the blades to the generator speed of over 1,500 RPM. As the generator spins, electricity is produced.

Function of The parts of a wind turbine (CON’T) BASE-In order to guarantee the stability of a wind turbine a pile or flat foundation is used, depending on the consistency of the underlying ground. TOWER-The tower construction doesn’t just carry the weight of the nacelle and the rotor blades, but must also absorb the huge static loads caused by the varying power of the wind. Generally, a tubular construction of concrete or steel is used. An alternative to this is the lattice tower form.

ADVANTAGES Of WIND POWER A Renewable Non-Polluting Resource Wind energy is a free, renewable resource, so no matter how much is used today, there will still be the same supply in the future. Wind energy is also a source of clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases. According to the U.S. Department of Energy, in 1990, California's wind power plants offset the emission of more than 2.5 billion pounds of carbon dioxide, and 15 million pounds of other pollutants that would have otherwise been produced. It would take a forest of 90 million to 175 million trees to provide the same air quality. Cost Issues Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators. Roughly 80% of the cost is the machinery, with the balance being site preparation and installation. If wind generating systems are compared with fossil- fueled systems on a "life-cycle" cost basis (counting fuel and operating expenses for the life of the generator), however, wind costs are much more competitive with other generating technologies because there is no fuel to purchase and minimal operating expenses.

DISADVANTAGES Of WIND POWER Environmental Concerns Although wind power plants have relatively little impact on the environment compared to fossil fuel power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and birds and bats having been killed (avian/bat mortality) by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants. Supply and Transport Issues The major challenge to using wind as a source of power is that it is intermittent and does not always blow when electricity is needed. Wind cannot be stored (although wind- generated electricity can be stored, if batteries are used), and not all winds can be harnessed to meet the timing of electricity demands. Further, good wind sites are often located in remote locations “COUNTRY!!!” far from areas of electric power demand (such as cities). Finally, wind resource development may compete with other uses for the land, and those alternative uses may be more highly valued than electricity generation. However, wind turbines can be located on land that is also used for grazing or even farming.

FACTS AND REVIEW Human civilizations have harnessed wind power for thousands of years. Early forms of windmills used wind to crush grain or pump water. Now, modern wind turbines use the wind to create electricity.   Today’s wind turbines are much more complicated machines than the traditional prairie windmill. A wind turbine has as many as 8,000 different components. Wind turbines are big. A wind turbine blade can be up to 260 feet long, and a turbine tower can be over 328 feet tall -- taller than the Statue of Liberty. Higher wind speeds mean more electricity, and wind turbines are getting taller to reach higher heights above ground level where it’s even windier. U.S. wind energy industry currently employs more than 73,000 people. 

FACTS AND REVIEW (CONT) The technical resource potential of the winds above U.S. coastal waters is enough to provide more than 4,000 gigawatts of electricity, or approximately four times the generating capacity of the current U.S. electric power system. Although not all of these resources will be developed, this represents a major opportunity to provide power to highly populated coastal cities. See what the Energy Department is doing to develop offshore wind in the United States. The United States’ wind power capacity reached more than 65.8 gigawatts by the end of 2014.That’s enough electricity to power more than 17.5 million homes annually -- more than the total number of homes in 15 STATES. Wind energy is affordable. Wind prices for power contracts signed in 2014 and levelized wind prices (the price the utility pays to buy power from a wind farm) are as low as US$2.35 cents per kilowatt- hour in some areas of the U.S. By 2050, the United States has the potential to avoid the emission of more than 12.3 gigatonnes of greenhouse gases and save 260 billion gallons of water by continuing to increase the amount of wind energy that powers our homes.