 Welcome!
 Last day to turn in permission slip
and $5
 Please get out paper for notes and
read the board and power up.
Today’s lesson
 Nearpod.com
 Look for join session in upper right corner
Harnessing the Wind – we’re
#1!
 Current largest wind
farm: Horse Hollow
Wind Energy Center
 421 wind turbines
 735 megawatts.
 47,000 acres of land in
Taylor and Nolan
County, Texas.
Texas’ next “cash crop”?
 500,000 Texas homes
currently, expanding 10
times in next decade
 In 2012, wind
generated 10,407
megawatts
 (1 megawatt = 500
homes)
 13% of state’s
electricity
How does it work?
How does it work?
 Area swept by blades
can be size of 747 plane
 Tips of blades can be
going 200mph
 Height – 240ft (taller
than Statue of Liberty)
 Nacelle – size of
greyhound bus
How does it work?
World’s largest German turbine: (394-feet)
behemoth capable of generating 5 MW
 Need 8 mi/hr winds to
generate electricity; max
electrical production at 1518 mi/hr winds; turbines
cut off at 55 mi/hr winds
 Yaw motor – nacelle moves
to face turbine directly into
wind
Applications
 Typical wind farm:
100Megawatts (MW)
 Coal fired power plant
– 500-600 MW
 One 1.5MW turbine
could power about 350
homes/year
Best wind is in the morning, but peak
demand is in the afternoon 
So what if you currently have wind
electricity? Do your lights go out
on still days?
Our electric “grid” = power
plants connected to consumers
Our electric “grid” = power
plants connected to consumers
Advantages
 High efficiency
 Moderate capital cost
 No air pollution
 Can use land for
grazing
 Renewable
 Domestic
 Able to use current
electric grid
Disadvantages
 Land use – requires




space
Visual pollution – some
people don’t like the look
Noise – 275 yards away,
it sounds like a
refrigerator
Bird and bat deaths
Winds peak in morning
and March-May
Wind in your home?