Download Wind Energy (Week 2)

Wind Energy (Week 2)
Connor Edmonds, Maura Eveld, John Michels
Environmental Impact
● Little to no real environmental impact.
● Impacts of the visual interruption that the large windmills have on the
landscape
● Windmills produce a lot of noise that people living near them frequently
complain about.
● Windmills also kill a lot of birds and bats that fly into the rotors of the
turbine.
● There is the positive impact that Wind energy offsets carbon emissions.
Wind Turbine Syndrome
● Is created by “nocebo” where people believe that wind turbines have
adverse health effects.
● So people who live near them constantly believe that all of their health
problems are caused by the wind turbines.
● People often also just get incredibly annoyed by the existence of the
surrounding turbines.
Types of Wind Turbines: VAWT
Vertical Axis Wind Turbine
● main rotor shaft positioned vertically
● Advantages
○ does not have to be pointed into the wind (good for variable-wind
locations)
○ better for building integration applications because it is less steerable
○ generator and gearbox can be placed near the ground -- more accessible
for maintenance
● Disadvantages
○ lower rotational speed and higher torque means higher drive train cost
○ lower power coefficient
Types of Wind Turbines: VAWT
Darrieus
Giromill
Savonius
Twisted
Savonius
Types of Wind Turbines: HAWT
Horizontal Axis Wind Turbine
● main rotor shaft and generator at top of
tower
● Advantages
○ variable blade pitch allow for optimal
angle
○ higher efficiency because blades move
perpendicular to the wind
● Disadvantage
○ Stronger tower construction needed to
compensate for heavy blades, rotor,
and generator
Types of Wind Turbines: HAWT
Dual-Rotor Coaxial Contra-Rotating Wind
Turbines
●
One large-diameter rotor and one small-diameter
turn in opposite directions
○
relative velocity between the two rotors is doubled, and
efficiency increases
○
air flow downstream is not disrupted as much (compared
to single rotor), so wind turbines downstream are able to
operate just as well
●
●
●
24% increase in efficiency, 20-30% decrease in
cost per kWh
Wind power density is greater
Smaller-diameter rotor can generate electricity
at lower wind speeds
Unconventional Wind Turbines
●
●
●
Massive conventional wind farms
cannot be constructed close enough
to heavily urban areas in order to
power enough energy for the city
Attempt to integrate wind energy
into urban areas in less intrusive
ways
Eiffel tower recently installed two
camouflaged wind turbines
○
expected to generate 10,000 kWh per
year
Wind Tree
●
Paris recently installed wind trees
this year
○
generate 3.1 kW each, but useful when
grouped can help out nearby homes and
office buildings
○
Can generate electricity at wind speeds as
low as 4.4 mph, but can withstand winds
up to 129 mph
●
●
“Leaves” oriented in such a way that
the turbines are noise cancelling
$35,000 per tree
Sources
http://www.azocleantech.com/article.aspx?ArticleID=191
https://en.wikipedia.org/wiki/Wind_turbine#Types
http://www.iflscience.com/technology/new-wind-turbine-looks-tree-coming-paris
https://books.google.co.uk/books?
id=wU9bgvrl4rQC&pg=PA38&lpg=PA38&dq=co+axial+dual+rotor+wind+turbine&so
urce=bl&ots=HvOfBbX0hK&sig=PNBr1IEwi8bXHp2YiAD4DutXGzc&hl=en&sa=X&ved
=0CEUQ6AEwCGoVChMIz_-x1JuuyAIVRM2ACh2PcQnc#v=onepage&q=co%20axial%
20dual%20rotor%20wind%20turbine&f=false
http://www.alternative-energy-news.info/eiffel-tower-wind-turbines/