What Do Homeowners Need to Know to Wind Power Their Homes?
Wind is a clean and green source of energy, and many environmentally-conscious homeowners are keen to exploit this resource. Domestic wind energy systems come in several sizes with varied capacities to meet your specific energy needs. These small energy-generating systems give you one more option to reduce your carbon footprint. But before you hurry to buy one, make sure that wind energy is the right choice for you.
Is Wind Energy the Right Choice for You?
Installing a domestic wind energy system makes sense if you live in a windy region and have at least an acre of vacant land on your property to house the components. The investment is economically feasible in remote regions where the cost of extending the utility power lines up to your house can be prohibitive or in areas where utility-provided electricity is expensive. However, you must make sure that the local zoning laws permit such installations.
A small domestic wind energy system can lower your power bill by 50-90 percent. Consider investing in one if your average monthly power bill exceeds $150, and your location is favorable for generating wind power. These systems can also power water pumps on farms and ranches; installing one on your property will lower your operational costs.
Do You Get Adequate Winds to Generate Electricity?
You can find out from wind resource data if your property receives adequate winds for a wind energy system to perform optimally.
The U.S. Department of Energy publishes wind resource maps for every state as part of its Wind Powering America Program.
You can obtain average wind speed information for your area from a nearby airport. Keep in mind that airports usually measure wind speed at heights about 20-33 feet above ground. The generator of a small wind power system is usually installed 80 feet above ground. At this height, the average wind speed is about 15-25 percent more than what is recorded at the airport.
The vegetation in an area can be a reliable indicator of wind speeds. Trees in windy regions are often permanently deformed, an effect known as flagging.
You can also calculate the wind speeds in your area with your own wind resource measurement device. You can buy one for as low as $600. However, ensure that you place it at a height where the generator will be installed to obtain accurate readings.
Generally coastal and flat rural areas receive strong winds that blow in smooth channels, unimpeded by obstructions like buildings and trees. Urban areas usually do not provide the best of conditions for generating wind electricity. These areas may receive strong winds, but this resource is very turbulent because of the significant ground clutter.
What Do You Need to Know About Zoning Regulations?
Zoning laws for installing domestic wind energy systems vary across jurisdictions. The local building inspector, the planning board, or the board of supervisors can tell you if you can install such a system on your property and if allowed, what restrictions you must adhere to. Usually, most zoning laws restrict the height of the structure to 35 feet, but there are variations of this limit.
Sometimes homeowners’ associations might object to the installation of a wind energy system citing noise issues. However, most domestic wind turbines are only slightly noisier than the ambient wind. You can make out their sounds from the surrounding noise only if you try to listen intently.
Should You Go Off-Grid?
Going off-grid sounds like the most obvious choice for someone who wants to live green, but this is not always practical or economically feasible. There are also several powerful advantages of remaining attached to the grid. Before you decide, weigh the pros and cons.
Going off-grid gives you energy independence. You do not have to go through the inconveniences of power outages. If you live in a remote region, going off-grid saves you the expense of running a power line to your house. There is also the immense satisfaction of knowing that you are generating clean power.
But going off-grid is not without its hassles. Relying solely on a wind energy system to meet your domestic power needs is economically viable only if you live in an area where the average annual wind speed is at least nine miles per hour. The winds should be blowing fairly regularly too. However, you can counter these challenges by creating a hybrid power system. Install a small solar electric system to meet your power needs on days when the wind is not strong enough.
But even with a hybrid power system, you must additionally invest in batteries to store the electricity you generate for those days when both the wind and the sun fail you. These batteries must be replaced, usually every 6 to 10 years. Else, you can buy a generator that runs on natural gas or bio-diesel fuel. But this backup generator will have its fuel and maintenance expenses. So off-grid systems are slightly more expensive than grid-tied ones.
Grid-tied wind power systems let you sell the excess electricity that you do not consume to the local utility. State net metering rules allow such arrangements on monthly or annual basis. This gives you the opportunity to earn money from the clean energy you generate with your system.
What Do You Need to Buy?
A small wind energy system comprises a wind turbine, a tower to mount the turbine on, and a set of balance-of-system components.
The most cost-efficient and productive wind turbines for residential energy systems are horizontal-axis, upwind machines with two or three blades. The turbine supports the rotor, generator, and tail. The amount of energy the turbine produces is determined by the diameter of the rotor.
Wind speeds increase with altitude. Therefore, turbines are mounted on towers to gain access to stronger winds. When the speed of the wind available to the system is doubled, the generator produces about eight times more power. So even a small investment to increase the height of the tower yields proportionately more in terms of the power generated.
Wind energy systems also need a smooth flow of wind to produce optimal power. This means the turbine should have unimpeded access to winds.
Here’s a general rule of thumb to determine the minimum tower height for your property. The tower should be tall enough, so the turbine rotor or the blades are at least 30 feet above the tallest obstruction within 300 feet. If there are trees nearby, consider the height of the mature tree. Also take into account the height of any building that might come up in future.
Towers can be self-supporting (free-standing) or guyed.
Guyed towers are less expensive than the self-supporting ones and easier to install. The tilt-down versions of the guyed tower are convenient because these can be lowered to the ground for maintenance work or during hazardous weather conditions. However, guyed towers require more housing space than self-supporting ones.
Both grid-connected and off-grid wind energy systems must be fitted with a set of balance-of-system components that safely transmit the electricity from the system to the loads that will use the power. The components differ depending on the application and in some cases, on the use the system will be put to. For instance, the parts needed for a system that will power a water pump are different than those for a machine that meets domestic needs.
The typical balance-of-system components for both grid-connected and off-grid systems are storage batteries; a charge controller to regulate the flow of electricity to the load; an inverter to convert direct current (DC) electricity to alternating current (AC) electricity that will power electrical appliances; safety equipment like electrical disconnect switch, grounding devices, and surge protector; and meters and instrumentation to measure battery voltage, charge, and the amount of power generated and consumed .
Usually, manufacturers provide the complete package for an application, so you don’t have to hunt around for the parts.
What Sized Wind System Do You Need?
To figure out the size of the wind system you must install to meet your domestic power needs, you must first determine your energy requirements.
This is a good opportunity to do an energy audit of the house to determine if you can lessen your electricity needs. The more energy-efficient you are, the smaller is the size of the wind system that you need for your home.
Gather your power bills for the past year to calculate average consumption. Also, make a note of the seasonal variations in your consumption pattern, if there is any. Maybe your heating bills are more than cooling costs? These findings will help you determine if you have to install a larger wind system or a hybrid energy system to counter the seasonal fluctuations in wind speed and meet your increased power needs during a particular season.
A manufacturer can help you determine the size of the system you need. Be ready to provide details like your average annual power consumption, the average annual wind speed in your locality, the average number of hours the wind blows at a particular speed, and the height of the tower that you will buy.
How Can You Choose the Windiest Site on Your Property?
You should install your wind energy system on the windiest site on your property to make it churn the maximum electricity and help you reap the most from your investment.
Wind speeds may vary within the same property especially if you live in a hilly terrain. The turbine will have more access to prevailing winds if you install the system on top of a hill or on the windward side of a hill. Installing the system in a gully or on the sheltered side of a hill is like placing a solar panel in the shade. When you install the system, ensure that the turbine is upwind of any obstruction nearby.
When you choose an installation site, make sure there is enough room around to lower and raise the tower for maintenance work. If your tower is guyed, ensure there is enough space for the guy wires.
Whether you buy a grid-connected or an off-grid wind energy system, wires will run between the turbine and the various loads like batteries, house, and the water pump. Make sure that you choose an installation site from where the wire run is the shortest. A long wire run generates greater resistance, so more electricity is lost during transmission. So, grid-connected systems should be installed as close as possible to the connection point. Off-grid systems should ideally be installed as close as possible to the battery bank. If the installation site is far from your house, place the batteries and the inverter close to the wind turbine.
Additionally, you need space to store the batteries. This should be a well-ventilated area away from living spaces and electrical appliances. Storage batteries contain toxic chemicals and emit hydrogen and oxygen when they are being charged. This space should also not be subject to temperature extremes. Make sure there is enough space around the batteries for you or someone else to access them for maintenance, repair, and replacement.
It can be exciting to imagine powering your home with wind energy. You can save money while living off the earth’s natural resources (without depleting them). With your careful planning, wind can allow you the power to live the life of your dreams in a way that you may not have ever thought possible.
Solid Rock Custom Homes has been remodeling and building custom homes in the Colorado Springs, Colorado area and the surrounding El Paso, Douglas and Teller counties since 1995. We would love to sit down with you to discuss or dream with you about your custom home. Please contact us at 719-494-0932 or request a consultation here. Check out some of our beautiful projects at http://www.houzz.com/pro/solid/solid-rock-custom-homes.