What are those ROTOR BLADES made of?
1. Wood laminates layered with epoxy, solid wood for small rotors
2. Steel and Aluminum Alloys
Spar and Skin construction (skeleton and outer skin, aviation technology)
3. Glass Reinforced Polyester or Wood/ Epoxy
4. Synthetic composites:
Polyester or epoxy matrix reinforced with glass fibers
Resin soaked glass Strands wrapped around forms
5. Hybrid Composities
Aluminum + thin Aramid (strong heat-resistant fiber such as Kevlar) or Carbon fiber and Epoxy Layers
6. Epoxy resin in Engineered Fabric
photo: ScienceDaily
ref: M Ragheb1-5
Owens Corning Ultrablade Fabric
Monday, June 27, 2011
Sunday, June 26, 2011
Thursday, June 23, 2011
Wind Power Blows Away Solar in the square footage category..
SOURCE WATTS AT FULL CAPACITY
One - 2 MW Wind Turbine 2 MW
Solar Panels: 181,818 Square Feet of them 2 MW
( 181,818 square feet is about 3.2 football fields )
(based on "nameplate capacity" - average capacity can be 75% lower than nameplate, and varies considerably with conditions and may be different between wind and solar. Solar calculated @ 11W/sq foot, field 360'x160' )
One - 2 MW Wind Turbine 2 MW
Solar Panels: 181,818 Square Feet of them 2 MW
( 181,818 square feet is about 3.2 football fields )
(based on "nameplate capacity" - average capacity can be 75% lower than nameplate, and varies considerably with conditions and may be different between wind and solar. Solar calculated @ 11W/sq foot, field 360'x160' )
Monday, June 20, 2011
The Answer, My Friend, Is Blowin' Harder In the Wind
WIND SPEED mph ENERGY GENERATED BY WIND TURBINE
20 X
25 2X
31.7 3X
40 4X
50 5X
Energy generated is proportional to the cube of wind speed. Make the tower a little taller, make the blades a little longer, get it in a little windier environment and the returns will be massive.
20 X
25 2X
31.7 3X
40 4X
50 5X
Energy generated is proportional to the cube of wind speed. Make the tower a little taller, make the blades a little longer, get it in a little windier environment and the returns will be massive.
![]() |
| Three Cubed Equals Twenty Seven |
Sunday, June 19, 2011
What is your Mercury Footprint?
Bulb type Source of electricity Mercury released
Incandescent 75-watt Coal 13.16 mg
not recycled
Incandescent 75-watt Coal 13.16 mg
recycled
Compact Fluorescent (equivalent) Coal 8.51mg
not recycled
Compact Fluorescent (equivalent) Coal 3.51 mg
recycled
Incandescent 75-watt Bulb Wind 0
not recycled
Incandescent 75-watt Bulb Wind 0
recycled
Compact Fluorescent (equivalent) Wind 5 mg
not recycled
Compact Fluorescent (equivalent) Wind 0
recycled
( calculated for a typical cfl 7500 hour bulb life equivalent light output to 75w incand., assumes 5mg Hg inside CFL; some newer CFL bulbs have reduced Hg levels ) (popularmechanics.com)
Incandescent 75-watt Coal 13.16 mg
not recycled
Incandescent 75-watt Coal 13.16 mg
recycled
Compact Fluorescent (equivalent) Coal 8.51mg
not recycled
Compact Fluorescent (equivalent) Coal 3.51 mg
recycled
Incandescent 75-watt Bulb Wind 0
not recycled
Incandescent 75-watt Bulb Wind 0
recycled
Compact Fluorescent (equivalent) Wind 5 mg
not recycled
Compact Fluorescent (equivalent) Wind 0
recycled
![]() |
| New GE Hybrid Halogen-CFL contains only 1 mg Mercury |
( calculated for a typical cfl 7500 hour bulb life equivalent light output to 75w incand., assumes 5mg Hg inside CFL; some newer CFL bulbs have reduced Hg levels ) (popularmechanics.com)
Thinking about Grass
LAWNMOWER TYPE LBS. OF CO2 RELEASED TO ATMOSPHERE
Gasoline ( 1 hour ) 30.53 lbs
Electric, from Coal ( 1 hour ) .66 lbs.
Electric, from Natural Gas ( 1 hour ) .26 lbs.
Electric, from Wind Power ( 1 hour ) 0 lbs.
Electric, from Solar Power ( 1 hour ) 0 lbs.
Hand ( 1 hour ) 0 lbs.
notes:
Gasoline and coal release a host of other greenhouse gasses as well as just CO2 - this post only looks at CO2. / Gasoline is 87% carbon - when it burns it combines with Oxygen and resultant CO2 weighs 3.7 times the original weight of the Carbon and greatly exceeds the weight of the gasoline itself. / Sample electric lawnmower specs : 13 amp, 120 v. , generated from coal at .95kg CO2/5 KwH, from nat. gas @.6kg CO2/5 KwH / sample Gasoline mower consumes 1.5 gal/hr ) (epa.gov , WolframAlpha ) Not reflected above, lawnmowers are particularly dirty and considerably more polluting than autos for a given amount of gasoline burned. // Also, some claim that coal-fired power plants may sit around in stand-by mode to back up wind and solar sources when they fail to generate sufficient power, and thereby increase their carbon footprint per KwH. Others claim that with good grid planning and design, this doesn't happen.
Gasoline ( 1 hour ) 30.53 lbs
Electric, from Coal ( 1 hour ) .66 lbs.
Electric, from Natural Gas ( 1 hour ) .26 lbs.
Electric, from Wind Power ( 1 hour ) 0 lbs.
Electric, from Solar Power ( 1 hour ) 0 lbs.
Hand ( 1 hour ) 0 lbs.
notes:
Gasoline and coal release a host of other greenhouse gasses as well as just CO2 - this post only looks at CO2. / Gasoline is 87% carbon - when it burns it combines with Oxygen and resultant CO2 weighs 3.7 times the original weight of the Carbon and greatly exceeds the weight of the gasoline itself. / Sample electric lawnmower specs : 13 amp, 120 v. , generated from coal at .95kg CO2/5 KwH, from nat. gas @.6kg CO2/5 KwH / sample Gasoline mower consumes 1.5 gal/hr ) (epa.gov , WolframAlpha ) Not reflected above, lawnmowers are particularly dirty and considerably more polluting than autos for a given amount of gasoline burned. // Also, some claim that coal-fired power plants may sit around in stand-by mode to back up wind and solar sources when they fail to generate sufficient power, and thereby increase their carbon footprint per KwH. Others claim that with good grid planning and design, this doesn't happen.
![]() |
| Lawnmower Injury ( flickr.com ) |
Tuesday, June 14, 2011
Offshore Wind Farms - Who's Hot and Who's Not
COUNTRY NUMBER OF OFFSHORE WIND TURBINES
U.S. 0
SWEDEN 80
NETHERLANDS 128
U.K. 436
DENMARK 403
GERMANY 101
JAPAN 7+
CHINA 34
SCOTLAND 2
U.S. 0
SWEDEN 80
NETHERLANDS 128
U.K. 436
DENMARK 403
GERMANY 101
JAPAN 7+
CHINA 34
SCOTLAND 2
Saturday, June 11, 2011
Tons and Tons of Concrete to Hold Up A Wind Turbine
TONS OF CONCRETE
Single On-Shore Wind Turbine Foundation 1200
(vestas.com)
Single Majestic Farm Wind Turbine Foundation 607
(windsystemsmag.com)
2000 Sq-Ft Home foundation, footing and slab 106
(4'x9" walls, 4" slab)
Olympic-sized Pool, filled with concrete 6599
One Average Cement Truck - filled 17
One cubic yard of concrete 2
Single On-Shore Wind Turbine Foundation 1200
(vestas.com)
Single Majestic Farm Wind Turbine Foundation 607
(windsystemsmag.com)
2000 Sq-Ft Home foundation, footing and slab 106
(4'x9" walls, 4" slab)
Olympic-sized Pool, filled with concrete 6599
One Average Cement Truck - filled 17
One cubic yard of concrete 2
![]() |
| Why so much concrete?? Oh... |
Wednesday, June 8, 2011
Alternatives Leave Nuclear in the Dust: Latest Figures
installed capacity
Alternatives 381 Gigawatts
Nuclear 375 Gigawatts
(World Nuclear Industry Status Report 2010-11: draft version)
"Capacity" and "actual production" are very different from each other, however. It will be some time before nuclear production falls behind alternative production, though nuclear is on a slow decline and alternatives are on a rapid increase. ( see www.cleantechnica.com for more depth )
"alternatives"
wind
biomass
waste-to-energy
solar
Alternatives 381 Gigawatts
Nuclear 375 Gigawatts
(World Nuclear Industry Status Report 2010-11: draft version)
"Capacity" and "actual production" are very different from each other, however. It will be some time before nuclear production falls behind alternative production, though nuclear is on a slow decline and alternatives are on a rapid increase. ( see www.cleantechnica.com for more depth )
"alternatives"
wind
biomass
waste-to-energy
solar
![]() |
| Fukushima Explosion Creates some Dust |
Tuesday, June 7, 2011
China Winning on Multiple Fronts
CARBON EMISSIONS ( Millions of Tons of Carbon Released into the Atmosphere )
China has just started beating the U.S. in Emissions from Fossil Fuels:
ELECTRICITY FROM WIND ( nameplate capacity )
CHINA 41,800 Megawatts
USA 40,181 Megawatts
ELECTRICITY FROM HYDROELECTRIC ( nameplate capacity )
CHINA 200,000,000 Megawatts
USA 97,000 Megawatts
POPULATION
CHINA 1,331,460,000
USA 307,006,550
AUTOMOBILES
CHINA 168,000,000
USA 62,000,000
China not winning on all fronts, though .......
U.S has more solar, more square miles, and more nuclear power.
Sunday, May 29, 2011
Solar Panel per-Watt Cost Drops over 57 years
1954 $250
1960's $100
1970's $20
1990 $7
2005 $3.50
2011 $1.48
(numerous sources, panel costs only, not-installed, averaged)
(NectarDesign solar panel sculpture)
1960's $100
1970's $20
1990 $7
2005 $3.50
2011 $1.48
(numerous sources, panel costs only, not-installed, averaged)
(NectarDesign solar panel sculpture)
Growth of Wind-Power Industry
A sampling of states and countries to show 9-year change in installed Wind Power Capacity:
( millions of watts )
2001 2010
Texas 1096 10,085
Washington 180 2104
Oregon 157 2104
California 1683 3177
Utah 0 223
Iowa 324 3675
Colorado 61 1299
New York 48 1275
China 400 41,800
India 236 13,000
United States 4275 40,181
Germany 8754 27,214
(windpoweringamerica.gov)
(lmwindpower.com)
(wikipedia.org/wiki/Wind_power_by_country)
( millions of watts )
2001 2010
Texas 1096 10,085
Washington 180 2104
Oregon 157 2104
California 1683 3177
Utah 0 223
Iowa 324 3675
Colorado 61 1299
New York 48 1275
China 400 41,800
India 236 13,000
United States 4275 40,181
Germany 8754 27,214
(windpoweringamerica.gov)
(lmwindpower.com)
(wikipedia.org/wiki/Wind_power_by_country)
Problems Reported with Wind-Power
Here are the objections to Wind-Power and Wind Turbines that are tossed around by groups opposing the industry. All should be discussed at length.
They look bad.
They're unreliable.
They kill birds.
Vegetation is destroyed.
Access roads and sites cause erosion problems.
Leakage of oil.
Wind turbulence affects local climate.
Noise.
CO2 emissions from the production of the concrete.
Bright navigation safety lights atop towers.
Consumption of water in production.
Adverse effects on land value.
Wind tower litter.
Adverse effect on tourism.
Social conflict is created.
They are inefficient.
They are a fire hazard.
They mess with TV reception.
They cause sunlight flicker.
Flying ice comes off the blades.
Electric bills will increase.
Ground wildlife is displaced.
New roads constructed through wilderness.
Existing roads damaged during construction phase.
Wind is unreliable.
Industry is subsidized by the taxpayer.
Desecration of sacred areas.
Disrupts radar and shipping lanes ( offshore wind )
Construction of massive new high-voltage transmission lines.
Farm animals are disturbed.
It doesn't make economic sense.
Greenhouse gas benefit overstated.
Price of coal-generated power goes up.
For some fascinating more detailed analysis of many of these objections see
http://ramblingsdc.net/Australia/WindProblems.html#Wind_is_intermittent
They look bad.
They're unreliable.
They kill birds.
Vegetation is destroyed.
Access roads and sites cause erosion problems.
Leakage of oil.
Wind turbulence affects local climate.
Noise.
CO2 emissions from the production of the concrete.
Bright navigation safety lights atop towers.
Consumption of water in production.
Adverse effects on land value.
Wind tower litter.
Adverse effect on tourism.
Social conflict is created.
They are inefficient.
They are a fire hazard.
They mess with TV reception.
They cause sunlight flicker.
Flying ice comes off the blades.
Electric bills will increase.
Ground wildlife is displaced.
New roads constructed through wilderness.
Existing roads damaged during construction phase.
Wind is unreliable.
Industry is subsidized by the taxpayer.
Desecration of sacred areas.
Disrupts radar and shipping lanes ( offshore wind )
Construction of massive new high-voltage transmission lines.
Farm animals are disturbed.
It doesn't make economic sense.
Greenhouse gas benefit overstated.
Price of coal-generated power goes up.
For some fascinating more detailed analysis of many of these objections see
http://ramblingsdc.net/Australia/WindProblems.html#Wind_is_intermittent
Wednesday, May 25, 2011
Noisy Wind Turbines
Distance guidelines and proposals for locating wind turbines away from homes include such recommendations as these:
1. 1.5x tower height
2. 3x blade height tip
3. 1000 feet
4. 2500 feet
5. 1 mile
6. 2 kilometers ( 1.24 miles )
7. whatever the complex computer models recommend
Noise is a REAL issue that affects enough people to be a serious concern - the sound is relentless and inescapable, and the annoyance levels, sleep disturbance, headaches and dizziness are concerns. Actual noise levels are affected by terrain, noise frequency, turbine model, wind direction and of course, distance. Perception of noise is affected by the personality of the person, the existing attitude about wind-power and the underlying ambient noise.
While many people aren't bothered, protecting the rights of even the minority who are is important to consider for something like this that bombards people 24 hours a day.
( see: www. windturbinenoises.org for one perspective )
1. 1.5x tower height
2. 3x blade height tip
3. 1000 feet
4. 2500 feet
5. 1 mile
6. 2 kilometers ( 1.24 miles )
7. whatever the complex computer models recommend
Noise is a REAL issue that affects enough people to be a serious concern - the sound is relentless and inescapable, and the annoyance levels, sleep disturbance, headaches and dizziness are concerns. Actual noise levels are affected by terrain, noise frequency, turbine model, wind direction and of course, distance. Perception of noise is affected by the personality of the person, the existing attitude about wind-power and the underlying ambient noise.
While many people aren't bothered, protecting the rights of even the minority who are is important to consider for something like this that bombards people 24 hours a day.
( see: www. windturbinenoises.org for one perspective )
Tuesday, May 24, 2011
Wind and Nuclear reality check
1 Nuclear Power Plant generates 12.3 million Megawatt-hrs/year
2708 Wind Turbines (1.8mw) generate 12.3 million Megawatt-hrs/year
975 Wind Turbines (4mw) generate 12.3 million Megawatt-hrs/year
( calculation based on a 28.8% capacity factor on a typical 1.8MW wind turbine / new 4mw offshore turbines with optimistic 36% capacity factor / average U.S. nuclear output 2009 - US Dept. of Energy stats.)
Wind Turbine Capacity
A 1.8 Megawatt Wind Turbine does not generate 1.8 MW 24-hours a day, 365 days a year! If it did, it would generate 15,768 Megawatt-Hours per year. On average in the U.S., wind turbines generate only 28.8% ( the capacity factor) of that amount, or 4541 MWh ( 4,541,000 KWh ) per year. There are wind-speed and direction variations and down-times for maintenance or excessive wind speed all of which combine to prevent the turbine from reaching even near full capacity. With the average home consuming 11,040 Kilowatt-hours per year (2008) assuming a 28.8% capacity factor, ...
...a 1.8 MW turbine will fully power 411 homes even with the down-time and wind variations. On average.
...a 1.8 MW turbine will fully power 411 homes even with the down-time and wind variations. On average.
Our Sources of Electrical Energy in the U.S.
Source Millions of Megawatt-Hours (MWH)
Wind 71
Solar .8
Fossil Fuels 2734
Nuclear 799
Hydro-electric 272
Bio-mass 52
Geothermal 15
(U.S. Dept. of Energy, 2009 stats)
Wind 71
Solar .8
Fossil Fuels 2734
Nuclear 799
Hydro-electric 272
Bio-mass 52
Geothermal 15
(U.S. Dept. of Energy, 2009 stats)
100% Renewables?
The Scottish National Party has set a goal to achieve 100% of electricity generated in Scotland by renewable sources in 9 years ( 2020 ). The economic and technological challenges are immense, but many say it could happen, others are skeptical. The Labour Party says that to go above 80% is unrealistic. Others say that 185% is achievable by 2030.
http://www.wind-watch.org/news/?p=8505
http://www.wind-watch.org/news/?p=8505
Monday, May 23, 2011
Recent Solar Industry Growth -
2009 20 billion Dollars
2010 90 billion Dollars - a gigantic change for one year.....considering that.....
...solar Industry growth rate averaged 30% for the last 20 years, still strong growth by any definition. (solarbuzz.com)
State and Federal incentives account for the huge increase in 2010. (solar energy industries assoc)
2010 90 billion Dollars - a gigantic change for one year.....considering that.....
...solar Industry growth rate averaged 30% for the last 20 years, still strong growth by any definition. (solarbuzz.com)
State and Federal incentives account for the huge increase in 2010. (solar energy industries assoc)
Wind Turbines Kill Birds
# of birds killed ( U.S.) annually
Wind Turbines .075 million - .25 million
Flying into windows 100 million - 900 million +
Auto/truck collisions 50 million - 100 million
Hunting 100 million+
Communication Towers 4 million - 10 million
Electrical Lines 67 million
Chickens killed for food 8395 million ( 8.4 billion )
Turkeys killed for food 5.3 million
Pesticide poisoning 67 million
Killed by Cats 100 million
(sources: US Fish and Wildlife, Smithsonian Inst., Nat Institute for Urban Wildlife, Am. Bird Conservancy, CurryKerlinger.com., Nat Audobon Society)
Wind Turbines .075 million - .25 million
Flying into windows 100 million - 900 million +
Auto/truck collisions 50 million - 100 million
Hunting 100 million+
Communication Towers 4 million - 10 million
Electrical Lines 67 million
Chickens killed for food 8395 million ( 8.4 billion )
Turkeys killed for food 5.3 million
Pesticide poisoning 67 million
Killed by Cats 100 million
(sources: US Fish and Wildlife, Smithsonian Inst., Nat Institute for Urban Wildlife, Am. Bird Conservancy, CurryKerlinger.com., Nat Audobon Society)
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