http://www.jetsongreen.com/2010/03/testing-a-new-dynamic-solar-facade.html
Wednesday, January 21, 2015
Wind
https://www.currentresults.com/Weather-Extremes/US/windiest-cities.php
City MPH KPH
Boston, Massachusetts 12.3 19.8
Oklahoma City, Oklahoma 12.2 19.6
Buffalo, New York 11.8 19.0
Milwaukee, Wisconsin 11.5 18.5
Dallas, Texas 10.7 17.2
Kansas City, Missouri 10.6 17.1
San Francisco, California 10.6 17.1
Cleveland, Ohio 10.5 16.9
Minneapolis, Minnesota 10.5 16.9
Virginia Beach, Virginia 10.5 16.9
Providence, Rhode Island 10.4 16.7
Chicago, Illinois 10.3 16.6
Detroit, Michigan 10.2 16.4
AIRFOIL TOWERS
https://www.google.com/search?q=airfoil+towers&espv=2&biw=1536&bih=729&source=lnms&tbm=isch&sa=X&ved=0ahUKEwig9Y2j1OnNAhVDbz4KHXZuA-YQ_AUIBigB#imgrc=_SOivd6sqHsoSM%3A
https://www.currentresults.com/Weather-Extremes/US/windiest-cities.php
City MPH KPH
Boston, Massachusetts 12.3 19.8
Oklahoma City, Oklahoma 12.2 19.6
Buffalo, New York 11.8 19.0
Milwaukee, Wisconsin 11.5 18.5
Dallas, Texas 10.7 17.2
Kansas City, Missouri 10.6 17.1
San Francisco, California 10.6 17.1
Cleveland, Ohio 10.5 16.9
Minneapolis, Minnesota 10.5 16.9
Virginia Beach, Virginia 10.5 16.9
Providence, Rhode Island 10.4 16.7
Chicago, Illinois 10.3 16.6
Detroit, Michigan 10.2 16.4
AIRFOIL TOWERS
https://www.google.com/search?q=airfoil+towers&espv=2&biw=1536&bih=729&source=lnms&tbm=isch&sa=X&ved=0ahUKEwig9Y2j1OnNAhVDbz4KHXZuA-YQ_AUIBigB#imgrc=_SOivd6sqHsoSM%3A
https://www.currentresults.com/Weather-Extremes/US/windiest-cities.php
Wind power generates 140% of Denmark's electricity demand
Wind power produced the equivalent of 42.1% of Denmark's total electricity consumption in 2015
50% by 2020,[6] and to 84% in 2035
50% by 2020,[6] and to 84% in 2035
UK To Build World’s Largest Offshore Wind Farm
http://www.renewableenergyworld.com/articles/2015/08/uk-to-build-world-s-largest-offshore-wind-farm.html
http://www.climatecentral.org/news/worlds-largest-offshore-wind-farm-to-be-built-in-uk-19995
http://www.windpowermonthly.com/article/1087016/low-wind-projects-technology-flourish
Tall Buildings: Structural Systems and Aerodynamic Form
UC online resource
A reduction of 10-20% of the cross wind building response can be attained by rotating the building to within 10 degrees of the wind direction.
According to study by Davenport, 70 story buildings exhibited 50% less lateral drift with circular plan vs square plan.
As the number of available prime wind locations has dwindled, developers are looking to lower-speed sites and manufacturers are responding with new turbine models
Wind technology has advanced to the point that turbines can now offer a 20-30% production gain compared with a year or two ago, making lower-wind sites in Class II and III areas more economically feasible.
In the US, for example, only around 10% of the country has high winds, while some 50% has low wind.
Many of the windiest or Class I sites with crucial transmission access have already been developed, notably in the US
Increase wind speed w/height:
https://www.google.com/search?q=average+airspeed+increase+with+height&biw=1745&bih=868&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj7p4Sp1rfKAhXM4yYKHfpcBwEQ_AUIBygC#tbm=isch&q=wind+increase+with+height&imgrc=m8XvYVndNP4YhM%3A
Where:
AEO = 0.01328 * D² * V³
AEO = Annual energy output, kWh/year
D = Rotor
diameter, feet
V = Annual
average wind speed, mph
AEO =
0.01328 * (20 ft)² * (19 mph)³ = 36,435 kWh/year
http://www.windpowerengineering.com/construction/calculate-wind-power-output/
http://www.wind-works.org/cms/index.php?id=43&tx_ttnews%5Btt_news%5D=2572&cHash=b74148dbab1938159937a994adf1f05b
http://www.energy.siemens.com/hq/en/renewable-energy/wind-power/SCOE.htm
http://inhabitat.com/architectural-wind-modular-wind-turbines/
https://www.google.com/search?q=ken+yeang&rlz=1C1CHWA_enUS551US551&espv=2&biw=2560&bih=1216&source=lnms&tbm=isch&sa=X&ei=HP-_VLL-N8ymyASO-IHQDw&ved=0CAYQ_AUoAQ&dpr=0.75
http://inhabitat.com/philippe-starck-unveils-two-revolutionair-wind-turbines/
About WIND SPEED:
http://energybible.com/wind_energy/wind_speed.html
Cut-in Speed - Cut-in speed is the minimum wind speed at which the wind turbine will generate usable power. This wind speed is typically between 7 and 10 mph for most turbines.
Rated Speed - The rated speed is the minimum wind speed at which the wind turbine will generate its designated rated power. For example, a "10 kilowatt" wind turbine may not generate 10 kilowatts until wind speeds reach 25 mph. Rated speed for most machines is in the range of 25 to 35 mph. At wind speeds between cut-in and rated, the power output from a wind turbine increases as the wind increases. The output of most machines levels off above the rated speed. Most manufacturers provide graphs, called "power curves," showing how their wind turbine output varies with wind speed.
Cut-out Speed - At very high wind speeds, typically between 45 and 80 mph, most wind turbines cease power generation and shut down. The wind speed at which shut down occurs is called the cut-out speed, or sometimes the furling speed. Having a cut-out speed is a safety feature which protects the wind turbine from damage. Shut down may occur in one of several ways. In some machines an automatic brake is activated by a wind speed sensor. Some machines twist or "pitch" the blades to spill the wind. Still others use "spoilers," drag flaps mounted on the blades or the hub which are automatically activated by high rotor rpm's, or mechanically activated by a spring loaded device which turns the machine sideways to the wind stream. Normal wind turbine operation usually resumes when the wind drops back to a safe level.
One of the key things to know about wind speed is that the amount of energy which wind can generate is not a one to one function. Rather energy increases by the cube of the wind speed. If you double the wind speed, you get eight times the energy. That is one reason that looking at wind maps is so useful. Even a small difference in wind speed within a given area can have a big impact on the amount of energy a wind turbine can generate. It is also one of the reasons why a taller wind tower can make so much of a difference. If the wind speed increases even a few miles an hour by going with a taller tower the energy generation potential goes way up (see sidebar chart).
Betz Limit
It is the flow of air over the blades and through the rotor area that makes a wind turbine function. The wind turbine extracts energy by slowing the wind down. The theoretical maximum amount of energy in the wind that can be collected by a wind turbine's rotor is approximately 59%. This value is known as the Betz limit. If the blades were 100% efficient, a wind turbine would not work because the air, having given up all its energy, would entirely stop. In practice, the collection efficiency of a rotor is not as high as 59%. A more typical efficiency is 35% to 45%. A complete wind energy system, including rotor, transmission, generator, storage and other devices, which all have less than perfect efficiencies, will (depending on the model) deliver between 10% and 30% of the original energy available in the wind.
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