Wind Energy >>
Harvesting the Wind
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Why
build wind farms here? |
In
Minnesota we have a huge supply of wind- Minnesota is the ninth
windiest state. This area of Minnesota, called Buffalo Ride
or Coteau de Prairie, is a glacier-deposited ridge that runs
diagonally across the state. Because of its higher elevation
of 1950 feet, the area experiences continual wind speeds of 18
mph. This and the plentiful open farm and pasture land make
it an ideal place for wind turbines. In
May of 2007, Governor Tim Pawlenty signed into law a renewable
energy requirement for 25% of the electricity prodced by state
utilities to come from renewable resources by the year 2025.
Click
here to read more. |
How
do they work? |
Wind
turbines operate on a simple principle. 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. |
How
big are the turbines? |
To
the hub, the turbines are 229 ft tall with 136 foot blades,
meaning the height from the base to the tip of the blade is 365
feet. The bases of the turbines are 11-16 feet in diameter
and the foundations, which run 30 feet into the ground, are 15.6
feet across. Each wind turbine weighs roughly 1450 tons. |
How
fast do the blades turn? |
At
the optimum wind speed of 25-35 mph, the blades will rotate at 14
rpm. That gives them a speed of 105 mph at the tip. |
|
How
much electricity do they produce? |
|
Each
turbine produces about 2,000,000 kilowatt hours (kwh) per
year, enough energy to power as many as 500 typical homes at
12,000 kwh per year. |
How
strong do the winds have to have to blow for the blades to rotate? |
Wind
turbines start operating at wind speeds of around 8 mph and reach
a maximum power or output at around 33 mph. When there is
not enough wind to turn the blades or when there is too much wind
(i.e. gale force winds at 50+ mph) the turbines are shut down. |
How
much do the wind turbines cost? |
It
costs over $2.5 million to set up a 1650 KW turbine. |
How
many turbines are there in Minnesota? |
Growing
at over 25% a year, wind energy is the fastest growing energy
source in the world today. There are somewhere between
1000 and 1200 wind in Minnesota with over 200 in Pipestone County
alone. |
Who
owns the land the turbines are on? |
|
Much of
the land is leased from local farmers. Each unit takes
up roughly 1/3 of an acre for the equipment and access
road. The farmer receives a percentage of the revenue
from the sale of electricity from each turbine. |
For
more information, visit: |
U.S.
Dept of Energy - Energy Efficiency & Renewable Energy American
Wind Energy Assocation Minnesota
Renewable Energy C-BED
Community Based Energy Development |
 |
|
Suzlon Wind Turbines located 5 miles east of Pipestone |
