Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
Ask a Question or Search InspectAPedia
InspectAPedia ® Home
ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
AIR CONDITIONING & HEAT PUMP SYSTEMS
AIR BYPASS LEAKS
AIR CHANGE RATE ACH HEAT SAVINGS
AIR FILTER EFFECTIVENESS
AIR FILTERING STRATEGIES
AIR FILTERING CONTINUOUS FAN OPERATION
AIR FLOW MEASUREMENT CFM
AIR POLLUTANTS, COMMON INDOOR
AIR LEAK DETECTION TOOLS
AIR LEAK MINIMIZATION
AIR LEAK SEALING PROCEDURE
APPLIANCE EFFICIENCY RATINGS
BASEMENT CEILING VAPOR BARRIER
BASEMENT HEAT LOSS
BIOGAS PRODUCTION & USE
BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
BRICK LINED WALLS
BUCKLED FOUNDATIONS due to INSULATION?
CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
COOLING LOAD REDUCTION by ROOF VENTS
COMBUSTION AIR for TIGHT buildings
CONDENSING BOILERS/FURNACES DAMAGE
DEFINITION of Heating & Cooling Terms
DUCT SYSTEM & DUCT DEFECTS
ENERGY SAVINGS in buildings
AIR CHANGE RATE ACH HEAT SAVINGS
AIR CONDITIONING HEAT PUMP SAVINGS
AIR LEAK SEALING PROCEDURE
ENERGY AUDIT - How to Use a Free One
ENERGY SAVINGS MAXIMIZE RETURNS ON
ENERGY SAVINGS PRIORITIES
ENERGY SAVINGS RETROFIT CASE STUDY
ENERGY SAVINGS RETROFIT LEAK SEALING GUIDE
ENERGY SAVINGS RETROFIT OPTIONS
ENERGY STAR PROGRAM
ENERGY USE MONITORING, SOLAR
HEATING COST SAVINGS METHODS
HIGH MASS TRADEOFFS, HEATING vs COOLING
HOUSE DOCTOR, how-to be
TIMERS for ELECTRIC WATER HEATERS
VENTILATION, BALANCED HEAT COST SAVINGS
ENERGY STAR PROGRAM
EVAPORATIVE COOLING SYSTEMS
FIREPLACES & HEARTHS
FLOOR RADIANT HEAT Mistakes to Avoid
FRAMING DETAILS for BETTER INSULATION
FRAMING DETAILS for DOUBLE WALL HOUSES
FRAMING METAL STUD PERFORMANCE
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
GEOTHERMAL HEATING SYSTEMS
GREEN BUILDING CONSTRUCTION CODES GUIDES
GREENHOUSE DESIGN for SOLAR HEATING
GREENHOUSE / SUNSPACE GLARE
HEAT LOSS in BUILDINGS
HEAT LOSS DETECTION TOOLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HEAT LOSS RATE CALCULATIONS
HEATING COST SAVINGS METHODS
HEATING OIL USAGE RATE
HEATING COST FUEL & BTU Cost Table
HEATING LOSS DIAGNOSIS-BOILERS
HEATING LOSS DIAGNOSIS-FURNACES
HEATING SYSTEM INSPECTION PROCEDURE
HOUSEWRAP AIR & VAPOR BARRIERS
HOUSEWRAP INSTALLATION DETAILS
HOUSEWRAP at SILLS, SOLES, TOP PLATES
HOUSE DOCTOR, how-to be
HOT ROOF DESIGNS: Un-Vented Roof Solutions
HUMIDITY LEVEL TARGET
ICE DAM PREVENTION
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
Insulation Air & Heat Leaks
INSULATION FACT SHEET- DOE
INSULATION for GREENHOUSE or SOLARIUM
INSULATION IDENTIFICATION GUIDE
INSULATION INSPECTION & IMPROVEMENT
INSULATION LOCATION - WHERE TO PUT IT
INSULATION R-Values & Properties
KIT HOMES, Aladdin, Sears, Wards, Others
LEED GREEN BUILDING CERTIFICATION
LEED Building Designation & IAQ
LOG HOME ENERGY EFFICIENCY
LOG HOME WALL INSULATION VALUES
MOISTURE CONTROL in BUILDINGS
RIGID FOAM USE INDOORS
ROOF VENTILATION SPECIFICATIONS
ROT, TIMBER FRAME
ROT, TIMBER ASSESSMENT
STRESS SKIN INSULATED PANELS
SWEATING (CONDENSATION) on PIPES, TANKS
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
THERMAL TRACKING & HEAT LOSS
THERMOSTATS, HEATING / COOLING
VAPOR BARRIERS & CONDENSATION in BUILDINGS
WALL CONSTRUCTION BARRIER vs CAVITY
WIND ENERGY SYSTEMS
WIND TURBINES & LIGHTNING
WIND WASHING INSULATION At EAVES
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
This article describes common types of windmills used for water pumping and electrical energy generating, from Cretan wind sails to Dutch Windmills to modern wind turbine electrical generator systems. Our page to photo shows a wind generator installed by Aero-Solar in San Miguel de Allende, Mexico where by 2010 many local solar & wind power companies offered wind turbine and solar power generation installation services. Also see WIND TURBINES & LIGHTNING, see ENERGY SAVINGS in buildings and SOLAR ENERGY SYSTEMS. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
What is Wind Energy and How is Wind Power Generated?
According to the Pennsylvania DEP who provide a brief introduction to wind power, wind energy systems are mechanical or electro-mechanical equipment that turn the force of moving air (wind) into mechanical energy (such as operating a mechanical pump to lift water from a well into a reservoir) or into electrical energy (operating a wind turbine or motor that converts the rotation of a wind-turned shaft into electrical energy). The text below is adapted from that source:
Modern wind generators (such as the small model shown in our page to photo) use advanced propeller designs whose blades maximize lift and minimize drag. Some propellers bend in high winds to avoid overspeed or damage. Both two-bladed and three-bladed propellers are used. On large wind generators the propellers may be more than 125 feet in diameter.
In January 2010 the New York Times reported that the U.S. is close to producing 2 percent of its electricity from wind turbines, and that wind power production grew in the United States during 2008 and 2009 by a total of 57%. [2008 (18%) and 2009 (39%)]., adding 9,900 megawatts of electrical energy in 2009 alone (according to the American Wind Energy Association).
Use of wind power and its increased growth may help reduce emissions of gases that cause the increasingly rapid worldwide problem of global warming. In January and February 2010 the New York Times reported that most of the wind turbines and wind energy being installed in the U.S. as well as most of the solar panels being used in the U.S. are being produced in China, and that G.E. (General Electric) makes nearly half the wind turbines used in the United States. U.S.
Most of this wind power growth was in large wind turbines delivered to wind farms primarily in Texas, Iowa, California, Washington, and Minnesota, and aided by President Obama's economic stimulus package. Put in context, this was about the same amount of energy production increase in the U.S. as was provided from growth in production of natural gas, and the combination of those two energy sources accounted for 80% of all new electricity generation capacity in the country. By 2020, experts report, energy derived from wind power could be about 180,000 megawatts. -- NY Times 1/26/2010.
Traditional Dutch Windmills and Vertical Axis Wind Powered Water Pumps
The Dutch windmill (below left) is a traditional horizontal-axis slow-speed windsail - suitable for pumping water. The split-barrel windmill (below right) is a low-cost home-made water pump system.
Other more efficient vertical axis windmill designs have been used or experimented with since the 1930's in the U.S., including the Darrieus vertical-axis rotor that looks like an oval embroidery hoop to a wind power novice. Vertical axis wind turbines (in the 1970's) were not self-starting and needed an electric motor to begin activity. Alternative vertical axis wind generator designs include the variable-pitch Cyclo-turbine (4KW at 25MPH wind) and a double-rotor helical wind generator.
Other than the Dutch traditional windmill (above left) originated in Crete and other Mediterranean countries where they have been used for water pumping for generations, a Cretan sail windmill is also a slow-speed system (tip speed ratio 0.75:1) but this inexpensive wind system is made of wood and sailcloth, turning at a maximum of about 50 rpm. In high winds the sails are reefed.
Sail windmills for electrical energy have been produced as home-made systems capable of generating about 200 watts at 15 mph winds. - McGuigan.
Multi-blade Windmills or "Fans" used for Pumping Water
Our page top photo shows a multi-blade water pumping windmill in use in Guanajuato, Mexico - these fans have been in widespread use in North American since the 1800's where on ranches and farms they have been used to produce water for both human and livestock use.
Water Pump Windmills: Photos of Windmills Used as Well Pumps & The Aer-Motor Windmill Company of Chicago, IL
Wind Generator Rotor Speed Control
The windmill in our Aer-Motor water pump windmill photograph (above left) was used a hinged tailpiece or rudder to either face the wheel into the wind or in high winds, to "feather" the wheel at right angles to the wind to reduce or stop its rotation.
For speed control traditional windmills of this type were able to adjust the direction of the tailpiece to divert the fan blades from the oncoming wind direction if wind speed was excessive.
What are Typical Wind Generator Towers & Turbine Heights
Tower height makes the most significant difference in wind generator output [taller is better], while site selection may be similarly important in avoiding turbulence or blocked winds.
Wind energy system heights vary significantly, from small rooftop mounted units on buildings in some areas, to common wind farm turbine heights of 80 meters (263 feet) to the turbine or, depending on blade length, a total height of about 112 m (370 feet) above ground.
Proven Energy who produce small scale wind turbine systems provides system masts are 11m (36 ft) and 15m (50 ft) tall.
Life Expectancy & Noise of Wind Generators & Turbines
The expected life of any renewable power source will vary by many factors, as we list and describe here. We collect and describe some of them here, and we develop a chart of trends in the anticipated life of wind generators by age, type, etc. [Contributions welcome, CONTACT us.]
Current estimated life for modern wind generator turbine designs range from 20 to 30 years
NWEA: 20 years
Proven Energy, UK: 20 - 25 years, extendable to 40 years with turbine refurbishing. Quoting:
National Wind: 20 to 30 years
But there can be considerable variation in both wind system life and its operating cost, depending on the factors we list below.
Factors Affecting Wind Energy System Life & Operating Costs
According to Proven Energy who describes the annual service for a modern wind generator,
Commonly-cited wear parts on wind generators include:
Typical Maintenance Costs for Wind Energy Systems
AEWA recommends that while wind system maintenance and repair costs will not be uniformly distributed over the life of the system, installers should allocate one percent of the installed cost of a wind energy system [per year] for operation and maintenance expenses over the life of the system.
For wind generators using a gear box drive rather than direct drive generators, annual gear box lubrication changeout doubles the estimated maintenance cost.
Early electrical generators using wind power operated using a copper-wound electric motor and carbon-arc brushes. Older wind energy texts such as McGuigan point out that the life expectancy of early motor generators was quite variable, from 20 years to just a year or so. Modern wind generators and turbines use alternators, eliminating the brush design, combined with a AC to DC rectifiers to produce DC electrical energy that is stored in batteries.
The New York Times, describing the wind and solar energy project in Tocco de Casuaria, in central Italy, reported (29 Sept 2010) that Tocco was chosen for an early European Union wind power demonstration project in 1989. "It had two inefficient wind turbines installed that lasted about a decade (half the wind turbine life expectancy in 2010) and were not replaced, meeting at best 25 percent of the town's electricity requirements.
According to the Times, Residents called the 1989 wind power installations 'sacks of noise' ". The Times article pointed out that recent improvements in wind turbine technology, quiet motors, and increasing costs for electrical energy prompted Tocco de Casuaria, to take a second look at wind power. Tocco (population 2700) installed two new wind turbines in 2007 and two more in 2009, now producing more electrical energy than the town consumes, and joining more than 800 Italian communities producing more energy than they consume.
Wind Generator or Turbine Noise Factors
According to National Wind, the following factors affect the [human-perceived] noise produced by wind energy systems:
National Wind describes the perceived noise of a modern wind generator installed to current standards as about that of a typical kitchen refrigerator. [We note that the noise of refrigerators itself varies quite widely depending on motor type, motor location, sound insulation, and fan use - Ed.]
Other Wind Generator & Wind Energy System Concerns
Wind Energy System Payback Time: according to Proven Energy,
Wind Energy Tower Shadow flicker: excessive shadow produced by the wind turbine rotor in bright sunlight - depends on latitude, sun angle, and perceived shadow dependence on wind tower setbacks from homes
Wildlife impact of wind energy systems: according to National Wind,
List of Wind Turbine Generator & Solar Energy Companies, San Miguel de Allende, Mexico Guanajuato
Ace Lab (52) (47) 7740055 Blvd Hidalgo 2006 Col Sn Jos Consuelo Cp 371 Len, GT
Frequently Asked Questions (FAQs)
Questions & answers or comments about buying, installing, using, maintaining wind energy systems: wind turbines
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
Lightning protection references & products for wind generators