Wind turbines convert kinetic energy from wind into electrical energy through the rotation of blades connected to a shaft that spins a generator. The generator produces electricity that feeds into the utility grid. Wind power produces zero emissions and uses minimal water and land compared to other energy sources. While wind power has small environmental impacts, concerns include effects on wildlife from collisions with turbines and visual or noise pollution. The United States uses wind power because it is a clean, renewable, and cost-effective energy source that can supplement other forms of electricity production.

1. The Production of Electricity
Power fromWind
Image Source: Leaflet,Wikimedia Commons Photo by Kim Hansen. Postprocessing (crop, rotation,
color adjustment, dust spot removal and noise reduction)
by Richard Bartz and Kim Hansen.

2. Wind Power
What does it look like?
Image Source: TennesseeValleyAuthority

3. Producing Electricity fromWind
How does it work?
1. Wind turns the rotor blades which turn a low speed shaft at about 30 to 60 rpm.
A motor may turn the rotor blades to face an optimal spot relative to the wind.
2. The gear box converts the rpm of the low speed shaft to a high speed shaft
which turns at over 1,000 rpm.
3. The high speed shaft drives an electricity generator.
Gear
Box
Rotor
Blades
(Slow Speeds)
Electricity
Wind
Generator
(Higher Speeds)

4. Producing Electricity fromWind
How does it impact the environment?
Air Quality and Greenhouse Gas Emissions from WindTurbines
• Wind power has ZERO GHG emissions and ZERO air pollution during use.
• Wind turbines produce small amounts of GHG emissions during manufacturing, transport,
and installation – about 0.05 pounds of carbon dioxide equivalent gases per kWh of energy
produced compared to 2 pounds per kWh for burning coal.
Gear
Box
Rotor
Blades
Electricity
Wind
Generator

5. Producing Electricity fromWind
How does it impact the environment?
Water Usage
Wind power uses no water during regular operation and only small amounts of water
during manufacturing and transport.
Gear
Box
Rotor
Blades
Electricity
Wind
Generator

6. Producing Electricity fromWind
How does it impact the environment?
Other Impacts
• Land Usage: Wind power uses about 30-140 acres per MWh, but only 1 acre is disturbed
permanently and about 3 acres temporarily during construction.
Gear
Box
Rotor
Blades
Electricity
Wind
Generator

7. Producing Electricity fromWind
How does it impact the environment?
Other Impacts
• Wildlife: Wind turbines can kill bats and birds, but they do so in small numbers,
and certain strategies such as keeping turbines still in low wind can reduce
deaths by as much as 50% without impacting power production.
About 388,000 birds
killed annually
About 1,400,000,000 birds killed annually
Image Source:
Leaflet,Wikimedia Commons

8. Producing Electricity fromWind
Why does the U.S. use wind power?
Wind energy is clean, renewable, abundant, and cost effective. Although it is not a
reliable and consistent form of electricity because of natural variations in wind speed
due to climate and season, it can be used to complement and supplement other forms
of electricity production.
Did you know?
While wind turbines have no public health impact and minimal environmental impact,
one of the major obstacles to installing more wind energy is that wind turbines can
annoy people through sound, vibration, shadow flicker, and perceptions of disturbed
landscapes.
Wind
Generating
Capacity in
2016
Image Source: Aflafla1,WikimediaCommons

9. Producing Electricity fromWind
What’s next for the U.S.?
Wind Energy is clean
and renewable with
minimal overall
environmental
impacts. It is
abundant, cost-
effective, and its use is
expected to expand
rapidly in the next
decade.
Image Source: NREL

10. Additional Impacts
http://comingalongside.org/Technology/
http://labs.ee.washington.edu/community/EnvironmentalImpacts/