The Answer My Friend Is Blowin’ In The Wind – well maybe for some of us!
The wind is a dynamic source of sustainable and renewable energy. and is the fastest-growing source of alternative energy worldwide. It has a proven, reliable track record and is much cleaner than energy extracted from fossil fuels.
Basically wind energy is produced when naturally occurring air movement (wind) goes through blades on a turbine causing them to turn. This movement turns the rotor creating mechanical energy. Kind of the opposite of a fan.
Residential wind power is a very environmentally friendly way to produce electricity. Costs are coming down and efficiency is increasing. One concern has been the danger to migrating birds and mammals. The Audubon Society states that the danger of residential wind power to birds is negligible. They feel that climate change is a true danger and that properly placed wind power is an important source of clean energy.
This article will discuss the basics of wind energy, the pros and cons of wind energy, where it works best, how it works, types of systems, and how to see if wind power is right for you.
For transparency, since I typically write about things I know and experience, I have not had wind energy. I have used solar power for the past 25 years. I do not have wind power because my area of Kentucky does not have the air movement to support wind power. However, many of my readers have asked for an article on wind for their homes.
For more information on solar energy check out the sidebar. We have many solar articles including:
Photo by Mila Young
Wind Energy and Civilization
What we refer to as “alternative energy” actually has a very long history. Maybe we should refer to it as Foundation Energy. Five thousand years ago, ancient Egyptians used the wind to power propellers on boats traveling on the Nile River.
The windmill and wind pump date back to the early Indus Valley and Civilizations Mesopotamia. The technology was brought back to Europe by early merchants and crusaders. During the Middle Ages, they began using windmills in food production and in the Netherlands for draining water. These systems transferred the wind into mechanical energy to do a task such as grinding grain.
The first modern wind turbine was constructed in 1887 in Glasgow, Scotland. The cloth turbines charged an accumulator and produced light for his home. Turbines since then have changed dramatically becoming more aerodynamic and efficient.
Interesting contrast. Photo by Shelley Pauls
Wind As a Source of Energy
Air movement occurs naturally over the earth. As the earth moves around the sun it tilts and revolves. The energy from the sun hits the earth in different places as it moves in its orbit. This causes temperatures on the earth’s surface to fluctuate. All of these systems combined cause air to move over planet earth.
You may remember from physics class that kinetic energy is energy in motion. Wind Power is based on volume and velocity. Volume is the amount of air (volume), and velocity is the speed at which the air is moving. Density is another factor. Density is the mass of the air. Dry air has a lower density than humid air.
Volume, velocity, and density are working in tandem to make the blades spin. Wind turbines actually some of the energy in this process. On average they are only thirty-five to forty-five percent efficient. However, technology is making improvements in models.
Turbines are becoming more efficient and quieter. In the past turbines were not an option for urban families because of the challenges of noise and the height of the tower. Newer models can be roof mounted and are much quieter.
Today’s Wind Energy – Better and More Powerful
This is a nice intro video on wind
Basic Parts of a Wind Turbine
www.windeis.anl.gov Parts of the turbine
Turbine
The turbine is a spinning mechanical apparatus that extracts energy. They are used with water, steam or air pressure to produce work.
Pole
Typically, especially in larger operations, the turbine is mounted on a tall steel pole. These poles may two hundred and fifty feet tall. Smaller systems use shorter poles or towers.
Many newer home turbines are made to be mounted on a rooftop or even a recreational vehicle. The opportunity for homeowners to install wind power has increased dramatically with new models.
Blade
Blades are made from metal or fiber-reinforced plastics. They are typically mounted horizontally to the pole. The way the blades are mounted effects how they will turn. Fixed pitch, either twisted/tapered, or straight.
However, many new turbines are being designed with blades that are vertical.
Nacelle
The nacelle houses the shaft, gearbox, rotor, generator, and controls. How much energy the system produces is determined by the size of the rotor.
Generator
The generator changes the energy from kinetic to mechanical. The generators are simply designed and easy to maintain. Climbing up and down a 250-foot pole is no easy task.
Average Costs of Residential Wind Systems
The U.S. Department of Energy states that industrial wind power costs an average of around 2 cents per kilowatt-hour (kWh) compared to coal-burning plants at 11 cents per kilowatt. Wind energy contributed 6.3% of the United States’ total electricity supply, over 10% of the total electricity generated in 14 states, and over 30% percent in Iowa, Kansas, Oklahoma, and South Dakota.
Residential costs and systems have also come down making it a desirable option for new construction. Wind systems can reduce your electric bill by 50 – 90 %, especially if your average electricity bills are $150 per month or more.
For people that live in remote rural areas, alternative energy is often the answer. Both solar and wind have upfront costs but then no monthly bill. Once you finish paying for your system your electric is essentially free - minus any maintenance. Keep in mind that the federal government and many states offer tax rebates for installing renewable energy in your home.
Remote Cabin
Wind energy works great for remote cabins and those of us off the grid.
My friend Jon has a remote cabin in Alaska and purchased the Missouri General Freedom II Wind Turbine. It is 2000 watts and currently, he is running lights, using the microwave, and charging his cell phone and laptop. In addition to the turbine, he had to put up a tower and buy the charge controller to regulate the electricity. Jon stated the turbine cost $ 990, charge controller $170 and installing a tower was another $1000 plus about $200 for cables and brackets. So @$2360.00 for a small system.
Urban Grid-Tied Example
One example of a grid-tied from a family who lives in Northern Ohio. The turbine, cost $15,000 to install which provides about four hundred kilo-watts hours of their total nine-hundred kilowatt-hours of electricity used. This model requires eight-mile-per-hour winds to start producing energy which works out well because their location averages ten to twelve mph. The estimated ROI was twelve years. (source)
Determine Your Wind Energy Needs
Determining your electrical needs and usage is important. If you are going to live “off-grid” and not be attached to conventional electricity then you need to work on reducing your level of energy consumption. You can do this by purchasing energy star appliances. Just switching to Energy Star LED light bulbs will save you considerable amounts of electricity.
We use kilowatts (kW) to measure energy output. For example, an incandescent hundred-watt light bulb uses one kWh after ten hours of use. According to the U.S. Department of Energy, the typical US residential customer uses about 909 kWh a month of energy or approximately 10,909 kWh a year.
Where Does Wind Energy Work Best?
Wind turbines need consistent speeds of nine miles per hour. Wind turbines are becoming more efficient and able to generate electricity at lower speeds. Some of the newer smaller turbines run at six miles per hour.
The keyword here is consistency. If you live in central Kentucky and you experience a windy day you may think “I should get wind power”. While that thought maybe a good one on a blustery day it will not serve you in the long run. People are often surprised when I tell them that we do not have enough wind in Kentucky to support efficient electricity production.
You can look up the wind speeds for your town in the United States on the Wind Exchange website.
According to the American Wind Energy Association, the best states for producing electricity using wind power are (from best to average)
North Dakota
Texas
Kansas
South Dakota
Montana
Nebraska
Wyoming
Oklahoma
Minnesota
Iowa
Areas along the northeast coast
States not on the list are considered below average for wind power.
Check out our events page for upcoming education programs.
DIY Measure Your Wind
An anemometer is a handheld tool that measures wind speed. I use a HOLDPEAK 866B which measures wind speed, temperature and wind chill. It’s inexpensive and works great.
Don’t just take one measurement. Take measurements on a daily schedule for several weeks to determine your average wind speed. Even better over several months. It makes a great experiment for kids.
Steps To Determine If Wind Is Right For You?
1. Determine the wind speed by using charts and an anemometer.
2. Check for zoning requirements
3. Think about your ROI (Return on Investment)
4. Location, location, location – do you have a good spot for a turbine
5. On-grid, off-grid or hybrid
6. Estimate your electric needs
Wind Turbines along highway in Illinois. Photo Ame Vanorio
What Size Wind System Do I Need?
The size of your wind system depends on how much electricity you need to produce. If you are grid-tied or a hybrid system then you can fall back on your conventional system. Is your goal to supplement your energy needs and reduce your electric bill?
Do you want to be off-grid and independent and have the wind provide all your power needs? If you plan on being off-grid you need to analyze your energy use carefully and determine what size system you will need.
It has also become popular to combine solar and wind power. Together they often pick up each other’s slack. When it’s dark the wind may blow and when the wind is calm the sun is may shine brightly.
I will say that one advantage of solar is that you can start very small and easily build on.
Small Systems
According to the US Department of Energy
Small wind electric systems can:
Lower your electricity bills by 50%–90%
Help you avoid the high costs of having utility power lines extended to a remote location
Help uninterruptible power supplies ride through extended utility outages.
Small systems range in size from twenty kilowatts to one hundred kilowatts (kW).
Small systems work well for home and farm applications. A small wind power system can furnish you with an adequate amount of electricity. Small turbines typically have a downwind turbine. This means the air current pushes from the back. They still need a strong, rigid tower but are flexible in the rotor and the generator.
Small vertical axes turbines are attractive and made to fit on RV’s or boats. The blades are made for low wind startups to be more energy efficient.
Mini turbines are designed for charging batteries or running lights in an RV or cabin. They run between 20 – 50 kW. The smaller or “micro” (20- to 500-watt) turbines are used in a variety of applications such as charging batteries for recreational vehicles and sailboats. Small turbines that produce 3 – 10 Kw are great for single application jobs such as pumping water from a well or running lights in a remote cabin.
If you enjoy DIY projects and want to make the blades and mounting hardware you can just purchase a generator. Marsrock makes a generator you can use for your homemade wind turbine.
Don’t have perfect conditions? A hybrid system such as the ECO LLC 850W Hybrid Solar-Wind Kit gives you 400W Wind Generator. Plus you get three solar panels that are 150W and a 1KW Inverter.
Figuring Out Costs
If you know a unit's capacity and efficiency factors, you can figure out the estimated annual output. Use this formula by multiplying year x day x capacity x-factors to get kW per year. If the unit has a rated capacity of 1500 kilowatts and an efficiency rating of twenty-five percent then the math looks like this:
365 x 24 x 1500 x .25 = 3,285, 000 kilowatt-hours per year
Remember this is the ideal. In real life, you have less or more wind on any given day.
You can use the NREL wind maps to adjust your time figures for a more accurate location-specific figure.
Installation
The installation of a wind energy system is an important and expensive part of the overall project. The success of how well the system works depends on the location of the tower and how you run the electrical cables into your house.
The taller the pole the deeper it needs to be planted. It will need to be cemented into the ground for safety. Guy wires are attached to provide extra stability for the tower.
This can be a DIY project or you can hire an installer.
Check your local zoning. Many states or city zoning laws require a licensed electrician to connect the power lines to your home.
Take Away
Renewable energy is a great way to meet your power needs and have a smaller carbon footprint. Wind works well in areas that have enough air current. Hybrid solar-wind systems are great too and can give you the best of both worlds.
I could not end this article without a tribute to Bob Dylans “Blowin’ In The Wind”
Author, Ame Vanorio has 25+ years of experience living off-grid and is an organic farmer. She is the director of Fox Run Environmental Education Center and a licensed wildlife rehabilitator. She teaches classes locally and online about organic gardening, green building, living off-grid and wildlife conservation. In addition, she is a freelance writer and writes for several gardening, tiny house and pet websites. She lives a sustainable life on her Kentucky farm with a myriad of domestic and wild animals.