Energy Tic-Tac-Toe Board Renewable Source - Wind Energy By: TJ Hoyt

What Makes Wind  The sun shines on land and water.  Land heats up faster than water.  Warm air over the land rises.  Cool air over the water moves in.

Wind in Action  When wind strikes an object, it exerts a force in an attempt to move it out of the way.  Some of the winds’ energy is transferred to the object, in this case the windmill, causing it to move.

History of Wind Energy 5000 BC Sailboats used on the Nile indicate the power of wind AD First windmills developed in Persia 1300 AD First horizontal- axis windmills in Europe 1850s Daniel Halladay and John Burnham build Halladay Windmill; start US Wind Engine Company Late 1880s Thomas O. Perry conducted 5,000 wind experiments; starts Aermotor Company 1888 Charles F. Brush used windmill to generate electricity in Cleveland, OH Early 1900s Windmills in CA pumped saltwater to evaporate ponds 1941 In VT, Grandpa’s Knob turbine supplies power to town during WWII 1979 First wind turbine rated over 1 MW began operating 1985 CA wind capacity exceeded 1,000 MW 1993 US WindPower developed first commercial variable- speed wind turbine 2004 Electricity from wind generation costs 3 to 4.5 cents per kWh 2011 Wind power provided over 12% of renewable energy used in US

Why Wind Energy?  Clean, zero emissions  NO x, SO 2, CO, CO 2  Air quality, water quality  Climate change  Reduce fossil fuel dependence  Energy independence  Domestic energy – national security  Renewable  No fuel price volatility

Wind Energy Natural Characteristics  Air density  Wind energy increases proportionally with air density  Humid climates have greater air density than dry climates  Lower elevations have greater air density than higher elevations  Blade swept area  Wind energy increases proportionally with swept area of the blades  Blades are shaped like airplane wings  10% increase in swept diameter translates into 21% greater swept area  Longest blades up to 413 feet in diameter  Resulting in 600 foot total height

How to Convert Wind into Electricity  Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.  A wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The winds turns the blades, which spin a shaft, which connects to a generator and makes electricity.  The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity.  Wind turbines are mounted on a tower to capture the most energy. At 100 feet or more above ground, they can take advantage of faster and less turbulent wind.

Advantages of Wind Energy  Wind energy is free.  Wind is a completely renewable resource because it is something that occurs naturally.  There is no pollution.  Wind energy is friendly to the surrounding environment, as no fossil fuels are burnt to generate electricity from wind energy.  Wind turbines requires less space than average power stations.  They are the lowest prices renewable resources.  They do not produce atmospheric emissions that cause acid rains and green house effects.  No water needed for operations.

Disadvantages of Wind Energy  The winds unreliability factor. In many areas, the winds strength is not enough to support a wind turbine.  Noise and aesthetics.  Wind turbines generally produce a lot less electricity than the average fossil fuelled power station, which means that multiple wind turbines are needed to make an impact.  Depending on how energetic a wind site is, the wind farm may or may not be cost competitive.  Wind energy cannot be stored (unless batteries are used).  Good wind sites are often located in remote locations.  Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation.  Sometimes birds and bats have been killed by flying into the rotors.

And Now  Modern wind power is a strong option for alternative energy and its rich history proves it can be used effectively.  Wind energy is very abundant in many parts of the United States.  Wind energy production was around 4% of total worldwide electricity usage and is growing rapidly.