Wind Energy for the EESP 2009. Two 800 Pound Gorillas. Climate Crisis. Oil Crisis. Two major issues that our students will be left to deal with:. Climate Crisis. Oil Crisis. Why Teach & Learn about Wind Power?. Wind is Fastest Growing Energy Source. US Installed Wind Capacity.
Wind Energy for the EESP2009
US Installed Wind Capacity
What is KidWind?
The KidWind Project is a team of teachers, students, engineers and practitioners exploring the science behind wind energy in classrooms around the US. Our goal is to introduce as many people as possible to the elegance of wind power through hands-on science activities which are challenging, engaging and teach basic science principles.
All very interesting but very little of the science and technology related to the current wind industry is presented.
In fact most text books are pretty negative about the future of wind and misrepresent the technology miserably.
Engineering is Elementary
Building simple blades
Building Wind Turbines
Testing Blade Parameters
Assessing Wind Resource
Kite or balloon string
Advanced Blade Design
School Siting Projects
Build Model (or full scale!) wind turbines
The pilgrims arrived under the power of wind. Cape Cod was home to the first windmill in America. Wind helped fuel our country’s early economy.
California Wind Turbines 1980’s
1.25 MW Turbine
Wind energy is created by uneven heating of the earth’s surface.
Land-sea breezes created by temperature differentials
Winds also stronger near shore because of long unobstructed fetch
Sea breezes typically strongest in late afternoon
Typically strongest in summer
Nighttime mountain breezes are stronger than daytime valley breezes
Mountain-valley winds can be enhanced by prevailing winds and convective flow between interior and coasts
Where is the Wind?
Average annual wind speeds may vary as much as 25% from year to year
Wind varies daily not only because of weather but because of convective heating
Winds typically strongest in mid-late afternoon
Convective heating is less of an influence in winter, when storms dominate wind patterns
Who is using the Wind?
Our own Wind Potential
Source: U.S. DOE
What is Wind Power Used For?
Generating electricity at Remote Sites
Producing electricity in parallel with utility
North American Farms in 30’s & 40’s
Boats & RV’s
Where can we find Wind Power Stations?
<4 ft rotor diameter
Mini / Cabin-size
3-10 ft rotor diameter
13-33 ft rotor diameter
33-200 ft rotor diameter
Turbines can be categorized into two overarching classes based on the orientation of the rotor
Vertical AxisHorizontal Axis
Lift Device “Darrieus”
Drag Device “Savonius”
Every few years a new company comes along promising a revolutionary breakthrough in wind turbine design that is low cost, outperforms anything else on the market, and overcomes all of the previous problems with VAWT’s. They can also usually be installed on a roof or in a city where wind is poor.
Blades rotate out of the wind when wind speed becomes too great
Blades are at a fixed pitch that starts to stall when wind speed is too great
Pitch can be adjusted for particular location’s wind regime
Active Stall Control
Many larger turbines today have active pitch control that turns the blades towards stall when wind speeds are too great
Environmental & Other Concerns about Wind
“As responsible citizens, stewards, and advocates, Mass Audubon strongly supports public policies and private projects that advance energy conservation and efficiency. We also support the development of wind farms, as a renewable energy source to offset the effects of global climate change produced by the burning of fossil fuels.” Sept. 21, 2004
Bird deaths in perspective
Yes -- Positively.
There is NO evidence from
existing wind facilities anywhere in the world (including locations very similar to Cape Cod that have offshore turbines) that wind turbines have a negative impact on property values or tourism.
In fact, the majority of studies conducted after wind farms have been built show that both tourism and property values increase!
Wind turbine at Exhibition Place, Downtown Toronto
Power in the Wind
Kinetic Energy = Work = ½mV2
M= mass of moving object
V = velocity of moving object
What is the mass of moving air?
= density (ρ) x volume (Area x distance)
= ρ x A x d
= (kg/m3) (m2) (m)
Swept Area: A = πR2 Area of the circle swept by the rotor (m2).
Swept are is proportional to square of the rotor diameter
20% increase in rotor diameter increases area by 44%
Doubling diameter increases area 4 times
No other factor is more important to the amount of power available in the wind than the speed of the wind
Power is a cubic function of wind speed
V X V X V
20% increase in wind speed means 73% more power
Doubling wind speed means 8 times more power
“Because speed distribution plays such an important role in determining power, it’s always preferable to use an actual measured distribution.”
Paul Gipe, Wind Power
Economics & Jobs
Sales & Marketing
Turbine Engineering (ME/EE/Aerospace)
Business Expertise (Financial)
Larger turbines are more cost effective per kW.
But the value of each kWh depends on whether it is used behind the meter (12-15 ¢/kWh )or sold to the grid (3-5¢/kWh).
Cape Cod Regional Technical School
African Windpower AWP 3.6 Turbine (installed June 2005)
(about half of an average household’s demand)
127 foot, tilt-up, guy-wired tower
SMA WindyBoy Inverter
Installed as an educational tool
Upper Cape Tech
Aircon 10 turbine
(2½ - 3 times an average household’s demand)
Freestanding, tubular, counterbalancing tower
2 SMA WindyBoy Inverters
* Rebate structure improved from Cape Tech to UCT example; rebate will be different for other applications, and additional incentives may be available.
--All prices are provided for example only – actual prices may vary--
The KidWind Project