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DIY Wind Energy

DIY: Wind Energy Set Up and Maintenance

Wind energy are an increasingly important part of the global energy market but keeping them properly maintained can present unique challenges.

Table Of Content

Incorrect solar heating of the atmosphere, topographical differences, and the Earth’s rotation all contribute to the production of wind, which carries with it kinetic energy. The wind patterns on Earth are influenced by the topography, water, and vegetation on the planet. Modern wind turbines can “capture” this wind flow (motion energy) and convert it into electricity. As long as there is sunlight, there will be wind, making this kind of power a renewable resource.

Now, how can we get this energy going? The wind’s kinetic energy turns the blades of a windmill or tower, which in turn spins the shaft of an internal turbine. Electricity is generated while the turbine’s shafts spin. That power is either sent directly to an individual home or neighborhood, shared among a group of neighbors, or pooled with that of other wind turbines in a wind farm and fed into the national power grid.


We invite you to read: “6 Steps for DIY Solar Panels: Installation Guide”


DIY Wind Energy

WIND ENERGY DESIGN AND SETUP

In order to facilitate the development of self-replicating and sustainable teacher/demonstration centers working for good global change, One Community seeks to provide sustainable and open-source-replicatable energy infrastructure. In our opinion, individuals who envision a more environmentally friendly and long-lasting future for electricity would benefit from additional how-to resources and how-to guides. It will take years for governments to link all these areas with their various state grids, but for now, millions of people throughout the world still lack access to dependable energy. We’re open sourcing wind energy design and setup to illustrate how anybody can make power by themselves.

People now have a greater opportunity than ever to generate their own renewable power source, thanks to the proliferation of renewable energy options and the steadily declining costs of technologies like wind, micro-hydro, solar, biogas, etc. When the proper technical knowledge of renewable energy systems is added to the mix, installation may be quite simple.

This has the potential to help:

  • Those seeking a healthier and more environmentally friendly way of life
  • Those living in areas where access to electricity is presently limited
  • The general public that wants more control, independence, and safety

Furthermore, in locations with insufficient solar radiation throughout the year, wind power may be the most viable renewable resource. The purpose of this open-source wind energy system tutorial is to provide a repeatable and user-friendly guide to evaluating, planning, installing, running, and maintaining one’s own wind energy system. More people will switch to using wind power if it can be shown to be practical, inexpensive, and appealing.

WIND ENERGY DESIGN & IMPLEMENTATION

You need to think about assessment, design, installation, and maintenance when planning a wind energy system, whether it’s connected to the grid or not. We’ll examine these 4 parts in depth using the example of a compact wind power system in the following chapters:

GRID-TIED VS. STAND-ALONE WIND SYSTEMS OVERVIEW

The use of wind energy may be implemented either as a grid-connected or a completely off-grid system. Each choice comes with benefits and drawbacks. Here is a synopsis of the two concepts. The following sections go into into detail on each individual part.

GRID-TIED WIND SYSTEM EXAMPLE

The following example of a grid-tied system shows how the electricity (AC) generated by a wind turbine is transferred to a controller, where part of that electricity is then distributed to adjacent homes, and the remainder is sent to the grid through a grid-tied inverter. By separating the wind system from grid faults, the grid-tied inverter protects the system’s power quality and frequency. Modern grid-tied inverters from Schneider Electric, ABB, etc. serve as controllers as well, reducing the amount of separate hardware required.

STAND-ALONE WIND SYSTEM EXAMPLE

A grid-tied inverter or utility connection is unnecessary in a self-contained system like the one seen below. As a result, the total cost of connections is reduced, but security and dependability are compromised as compared to being connected to the (often considerably more robust) electric grid.

However, this recognition of distinctions is merely the beginning. Find out whether wind energy is viable and legal in your area before making a final decision on a system. In order to make a final decision, please continue reading.

ASSESSMENT & SURVEYING

Wind may be a viable energy source, but only after it has been determined whether or not wind turbines can be legally installed, whether or not there is sufficient wind for a system, and where exactly the optimal location for development is. In the United States, a wind turbine may be prohibited in certain counties or required to have a permit in others. You should check the zoning laws and restrictions in your area before installing a wind energy installation. The county/local building inspector, board of supervisors, and/or planning board are the appropriate agencies to approach for this. You may find out whether a construction permit is needed, and if so, what documentation is needed, from them.

The next step is to determine whether or not your region gets sufficient wind, and if so, at what speeds. The velocity of the wind rises with altitude. The typical height of a 20-30 m wind turbine is used for small-scale energy systems. Thus, the wind velocity at that altitude is required.

There ought to be a database tailored to your nation if you don’t call the United States home. If not, you may look for information specific to your nation through meteorological websites or bureaus. If you can’t do that, try calling the local airport to see what the predicted wind speed is, or hire someone to do it for you.

Given that the normal cut-in speed for a wind turbine is 3.5-4 m/s (about 10 mph), if you live in a region with a generally steady wind speed of 5 m/s (about 10 mph) or higher, a small wind turbine may be a good option. Maximum power is generated between 10 and 12 meters per second, and in the event of a storm with gusts reaching 25 meters per second, the wind turbines are intended to cease running (by braking), protecting themselves from potential harm.

Find the optimal site for the wind tower before moving further with the wind energy system design. As a general rule of thumb, you should locate your wind tower where:

There is no significant obstruction within a 250-300 foot radius of the turbine.

In order to maximize efficiency, the turbine should be installed at a height of 25–30 feet above any potential wind barriers.

Due to the wind turbine’s height requirements and the necessity for space around it, installing it on a roof may be a viable option. If so, you’ll need to think about the durability of your structure and whether or not such an installation would be legal in your area. Once you’ve completed the evaluation and are satisfied that your site meets the requirements, you may go forward with the design of your system.

EVALUATION AND SELECTION OF EQUIPMENT

The process of evaluating and choosing new equipment begins with planning your electrical system and taking into account every step of the setup. Asking yourself the following questions can help you figure out what you can do on your own and where you may need assistance.

  • Is it possible to set up a concrete base and guy wires?
  • Is there any way I can get a lift or some other secure means of putting up the tower?
  • Do I understand the difference between direct current (DC) wiring and alternating current (AC) wiring?
  • Can I securely connect my turbine using my knowledge of electricity?
  • How well do I understand battery technology and am I able to install and manage them properly?
  • What do I understand about controllers, inverters, disconnect switches, and voltage stabilizers?

If you replied “yes” to all of these questions, it’s possible that you already have everything you need to build your own self-sufficient wind energy system. If there is anything you aren’t confident handling on your own, it’s best to consult an expert or learn more about the topic. Creating a little “test model” might also be useful.

STAND-ALONE VS. OFF-GRID SYSTEM EQUIPMENT CONSIDERATIONS

The next step is to settle on the specifics of your wind power installation. Both grid-connected and self-sufficient models exist. Named so because it operates independently from any other source of power, a “stand-alone” system relies on a battery to keep the lights on when the wind dies down. When the wind turbine is grid-connected, the power it generates is supplemented by the main grid, which steps in to cover gaps caused by the wind’s intermittent nature. In this setup, a disconnect switch is utilized in place of batteries.

The following are necessary for grid-connected systems to be viable:

  • You are located in a region where winds regularly exceed 10 miles per hour (4.5 m/s) on a yearly basis.
  • Costs associated with using power from your local utility company are high (above 10–15 cents per kilowatt-hour)
  • In other words, the costs associated with meeting the utility’s criteria to link your system to its grid are manageable.
  • Selling extra power or investing in wind power provides favorable financial rewards.

Independent units are preferable when:

  • A 9-mile-per-hour yearly average wind speed is common where you live (4.0 meters per second)
  • There is either no way to connect to the grid, or doing so would be prohibitively expensive. Costs of $15,000 to more than $50,000 per mile might be prohibitive when trying to connect a distant facility to the electric grid.
  • You’re hoping to cut your reliance on the power company by installing a solar power system.

If all the legal conditions are satisfied, the main deciding factor is generally financial ones. Although the upfront cost of batteries may be significant, the expense of connecting your distant site to the power grid may be far higher. Accordingly, a thorough assessment is required, and the following parts are meant to assist with that.

EVALUATING ENERGY NEEDS

One of the first things to do when creating a system is to assess the energy requirements. A wind turbine, tower, concrete base for the tower, and cable connections from the turbine to the equipment room are all necessary parts of any wind energy system, whether it is completely off the grid or linked to the grid. Your energy requirements will determine the optimal size and kind of this machinery.

When deciding on a wind turbine, for instance, you must consider:

  • Turbine size
  • Velocity of Wind at Mounted Turbine Height (determined during the Assessment and Surveying section above and needed to decide the cut-in speed)

A suitable size of turbine may be determined by energy forecasts tailored to your needs. An typical four-person American home uses almost the most energy in the world each year (12,000 kWh). Compared to the US, nations like India have a far lower average annual electricity use (about 900 kWh, but this varies widely throughout the country).

EVALUATING YOUR CAPACITY FACTOR

Consider your capacity factor next. To calculate the capacity factor, divide the average power output by the maximum output specified for the system. This varies from place to place, but you’ll need it so that your turbine is adequately sized to satisfy your demands.

Consider a wind turbine rated for five megawatts of peak power; if it only generates two megawatts of average electricity where you are, its capacity factor is forty percent (2 mW average 5 mW peak = 0.40, or forty percent). Since wind is a variable energy source, it will not always be able to power the turbine at its maximum efficiency. Therefore, the capacity factor will determine the design that will be enough to satisfy your demands.

The optimal capacity factor for wind energy systems is between 25 and 45 percent. The capacity factor of modern wind farms may reach 55% thanks to their optimized design. To provide some perspective, in an area where the average yearly wind speed is 14 miles per hour (6.26 meters per second), a 1.5-kilowatt wind turbine with a capacity factor of 30% can provide enough power for a residence that consumes 300 kilowatt-hours per month.

How do they come up with these numbers? For example, if a home uses 1000 kWh of energy per month and there are 720 hours in a month, then the necessary hourly power would be 1000 kWh / 720 = 1.4 kW. (1.388 rounded up). Assuming a capacity ratio of 30%, the minimum size of the turbine would be 4.67 kW (1.4/0.3=4.667), or 5 kW if rounded up.


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DIY Wind Energy

PURCHASING AND ACQUISITION

Most distributors of turbines and blades provide turnkey (operational) installations or the option for the client to buy components separately and have them installed by the distributor. To get more help from the firm, go with the first choice. The money you save and the knowledge you get by installing the turbine yourself are both substantial. Customers-to-be may consult with producers to learn about available choices and make an informed decision based on their preferences, available resources, and technical aptitude.

Treat the equipment acquisition like you would any other important investment. You will have to think about how much it will cost you and how much importance you place on durability in a design. Get product literature from many manufacturers and do some background research on the ones you’re interested in to make sure they’re reputable and that you can easily get your hands on replacement parts and servicing if required. Find out how long the warranty is and what it covers, and be sure to ask for recommendations from others who have installed a system similar to the one you’re thinking about buying. Inquire into the system’s functionality, dependability, upkeep, and repair needs, as well as whether or not the system is satisfying the needs of its owners. Once we have firsthand experience, we will also provide all of this information here.

The dealer should arrange for delivery of the turbine and blades, but if they don’t or if you’re offered a significant discount if you don’t use their delivery service, you’ll need a suitably sized vehicle and/or tow trailer to get the turbine home. Use caution around the equipment, and consider choosing self-delivery only if you have expertise with such tasks. Don’t put financial concerns ahead of your own safety.

PLACEMENT AND TOWER-TYPE CONSIDERATIONS

Wind turbines are most effective when placed in strategic locations. Extreme wind shears may develop on a plateau or mesa due to winds rushing from a cliff. The generator should be placed far enough away from the cliff to prevent interference from the wind.

Wind speed is increased on ridge tops because the wind is compressed when it sweeps over the peak of a hill. It’s possible that a shorter tower may be used if it were placed in a more advantageous location. However, no tower should be lower than 33 feet (10 m). The tower should be at least 20 feet (6 m) above the ground or the highest nearby object.

Extremely strong prevailing winds are common near the coast or a lake. Coastal areas get the majority of their wind from the ocean, therefore positioning your wind generator as near to the water as feasible is optimal. Downwind from the wind turbine, trees and higher buildings are acceptable.

No matter where it is installed, a wind turbine needs unobstructed airflow and space for its moving parts to function properly. Wind turbine efficiency drops and the turbine has to “work” harder in turbulent air. Most turbulences are caused by impediments, are strongest near the ground, and decrease as one gains altitude. There is a similar rise in wind speed with altitude. For optimal performance, a wind turbine should be mounted on a tower that is at least 20 feet higher than anything that may potentially block its path within 250 feet. However, keep in mind that significant barriers may still alter wind patterns at a distance of more than 250 feet away.

Typically, shorter towers are used for smaller turbines. Typically, a tower of 30-50 feet is used for a 1 kilowatt turbine installation, whereas a tower of 60-100 feet is required for a 10 kilowatt turbine. Mounting wind turbines atop tiny buildings where people reside should be carefully considered due to the inherent difficulties of turbulence, noise, and vibration.

Think about how you will build your tower into your decision of site. Tilt-ups, guyed lattice, and freestanding towers are the three primary alternatives. Tilt-up constructions often use pipe or tube and are held aloft using guy wires. They are put together below ground and hoisted into place using a winch or towed vehicle. This tower is the most cost-effective choice for turbines with a rotor diameter of 12 feet or less. Guyed lattice towers may be built horizontally and hoisted into place using a crane, or they can be stacked vertically, one part at a time. These towers are the most budget-friendly alternative for fixed-tower turbines, and they are often utilized for rotors with a diameter of less than 25 feet. There are two main types of freestanding towers, including lattice and monopole. The lattice tower requires no foundation and is often erected on the ground before being hoisted into place using a crane. Towers of this size are normally reserved for turbines with rotor diameters of twenty feet or more, and their high cost is due to the huge base size required. In addition to traditional towers, tilt-up monopole designs are becoming more popular for a wide range of turbine sizes. A monopole may seem more appealing than other tower designs, but it will cost you more money and take the longest to build since it needs the widest base.

Towers, especially guyed towers, may be provided with a hinge at their base and a winch or vehicle to tilt them up or down. All work may now be performed safely on the ground. While certain towers and turbines may be set up by the buyer with little difficulty, others should be left to experts. A wire with a latching runner is one kind of anti-fall device that may be installed and is strongly suggested for any tower that will be climbed.

Don’t use an aluminum tower because of how easily they shatter. Towers may often be purchased directly from the manufacturer of a wind turbine to assure optimal compatibility of all components.

Remember to be careful while installing wind turbines on top of houses. Larger residential wind turbines cause vibration and noise transmission to the mounting structure. The loudness and instability in the building’s framework might both result from vibration. The generator’s lifespan may be shortened if it is mounted on a rooftop, where it is subjected to high levels of wind.

After we’ve selected and set up our own tower, we’ll film a series of instructional videos and post them online.

NOISE ISSUES

Some noise is produced by smaller wind turbines, although it is usually not enough to be considered annoying. The average household wind system is quieter than a washing machine. Wind generators designed for homes are typically direct-drive machines with minimal moving components. These turbines are not equipped with fast transmissions like the massive turbines utilized in utility-scale wind farms. Therefore, the majority of the noise produced by a home-sized wind turbine is aerodynamic noise from the blades. Most current home turbines produce noise levels that, under typical wind conditions, are comparable to those of the surrounding environment. You can hear it if you go outside and listen for it, but it is no louder than a standard household appliance.

As an aside, you won’t notice any disruption in your TV signal if you install a few tiny wind turbines. Homes within a few kilometers of a major wind development that have TV antennas positioned in the direction of the turbines are, in general, the most vulnerable. Unfortunately, contrary to popular belief, wind turbines may cause interference on digital television. However, smaller turbines are less likely to interfere with TV and radio signals. If this does happen, it will likely be contained to a small area and be straightforward to fix technologically.

UNDERSTANDING WIND-SYSTEM COMPONENTS

In this part, we’ll go over the fundamentals of a wind energy system, including a breakdown of how grid-connected and off-grid installations vary in terms of key components and an analysis of why that matters. Having a firm grasp of the following parts of the system should help you make more informed decisions:

  • Wind Generator
  • Tower
  • Brake
  • Controller
  • Dump Load
  • Battery Bank
  • System Meter
  • Main DC Disconnect
  • Inverter
  • AC Breaker Panel
  • Backup Generator

Wiring, grounding, and other ancillary items are also a part of the system, although we won’t go into detail about them here.

Electricity is produced by the wind generator (also known as a wind genny or wind turbine). Modern wind generators are typically upwind designs (with the blades on the side of the tower that faces into the wind) that connect permanent magnet alternators directly to the rotor (blades). Since they strike an excellent mix between efficiency and rotor balance, three-bladed wind turbines are the most prevalent kind.

As a kind of self-preservation, small wind turbines may alter the rotor’s pitch by angling it upwards or to the side, or they can change the direction and speed at which the blades spin. Down the tower, cables carry electricity, often in the form of three-phase, alternating current (AC).

The voltage and frequency shift with the wind turbine’s rotation speed, thus the name “wild” power. The power is converted to direct current (DC) and used to recharge batteries or sent into the power grid.

The tower for a wind generator may be more costly than the turbine itself. The tower elevates the turbine so that it faces the “fuel”—the calm, powerful winds that generate the greatest power. To back this up, as was previously said, place wind turbines at least 30 feet (9 m) higher than anything within 250 feet; double this or even more if the item is a significant land feature.

Tilt-up towers, fixed-guyed towers, and free-standing towers are the three most prevalent forms of structures of this kind. In order to prevent lightning damage to equipment, towers need to be designed for lateral thrust and turbine weight, and must be suitably grounded.

Most wind turbines contain a brake (also known as an emergency shutoff mechanism) that allows the turbine to be stopped in the event of an emergency, during normal maintenance, when the turbine needs repair, or while electricity is not being used. In order to stop a turbine from spinning, many of them are equipped with “dynamic braking,” which just disconnects the three phases of power. Some have a disc brake, while others use a drum brake that is operated by a winch at the tower’s base. The rotor may be swung out of the wind on some of the others using a mechanical furling system. In most situations, mechanical braking is superior than dynamic braking in terms of efficiency and dependability.

The major purpose of a charge controller (also known as a controller or regulator) for a wind-electric system is to prevent the battery bank from being overcharged. It achieves this by keeping tabs on the battery bank and diverting power to a dump (diversion) load once the bank is at capacity.

Rectifiers and charge controllers for wind energy systems are often housed in the same enclosure (AC-to-DC converters). Overcurrent protection must be installed in series with the battery, controller, and dump load.

In normal operation, the inverter sells whatever electricity the turbine generates, hence the controller is unnecessary in battery-free grid-tie setups. However, there will be a control function for when the grid goes down, and there may be electronics installed before the inverter to adjust the input voltage.

Dump Load (also known as Diversion Load or Shunt Load) allows solar electric modules to be open circuited without consequence. For the most part, unloading your wind generator is not a good idea. Because of their high speed and volume, they may even blow up. You can’t use them without hooking them up to some kind of battery bank or load. As a result, a charge controller that may also act as a diversion controller is often used. Extra power generated by the battery bank is diverted by a controller and applied to a dump load. Alternatively, a series controller (often seen in PV systems) physically opens the circuit.

In order to make maximum use of the power produced by a wind generator, a dump load (also known as an electrical resistance heater) must be large enough to meet the load. When the batteries or the grid are unable to take the energy generated, the charge controller turns on the dump loads, which may be air or water heaters.

If you have a battery bank (or “storage batteries”), then anytime the wind speed is greater than the “cut-in speed,” your wind generator will generate power. A battery bank, a collection of batteries connected in series, is essential for an off-grid system to provide continued power even when the wind dies down. Batteries for off-grid systems are usually large enough to power a home for three quiet days. Additionally, battery banks may be a part of grid-intertied systems to serve as a backup power source in case of power outages. Because their only function is to keep essential electric loads running until the grid goes back up, these battery banks will often be smaller than those used for going completely off the grid.

In wind-powered installations, only deep-cycle batteries (those designed to be often thoroughly depleted to use most of their capacity) should be used. Most of these batteries run on lead-acid, which is why they are so prevalent. Standard maintenance for flooded lead-acid batteries include topping up the water content with distilled water on a regular basis to compensate for the water evaporated during the charging process. AGM batteries, which are sealed to prevent leakage, are ideal for grid-connected systems, in which they are normally maintained at full power. To avoid damage from freezing temperatures, sealed gel-cell batteries are a viable option in unheated areas.

The system meter (also known as a battery monitor, amp-hour meter, watt-hour meter, kilowatt-hour meter, or utility meter) monitors and displays the performance and status of your wind-electric system, including the amount of energy stored in the batteries, the amount of energy generated by the wind turbine, and the amount of energy consumed. Without proper metering in place, your system is like a vehicle without dials. Although it is theoretically possible to drive without checking the fuel gauge, doing so is not recommended. The utility provider often provides free internet-enabled meters.

In battery-powered systems, the batteries and inverter must be disconnected. This is referred to as the “main DC disconnect.” Typically, this disconnect is a big breaker with DC ratings that is housed in a metal box. This breaker protects the inverter-to-battery cabling from electrical fires and enables the inverter to be readily detached from the batteries for servicing.

The inverter (also known as a DC-to-AC converter or power conditioning unit) converts the DC energy generated by your wind generator into the AC electricity often used to power lights and appliances in houses. Wind energy may be fed into the utility grid via the use of grid-tied inverters, which synchronize their output with the grid’s “utility grade” AC power.

Many grid-tie inverters may be used with or without batteries, depending on the system’s needs. A battery charger, which can charge a battery bank from either the grid or a backup generator during overcast weather, is often included in battery-based inverters for off-grid or grid-tie systems. Some examples of inverters include the Sunny Boy, Siemens, and others.

All of a house’s electrical cabling connects to the “provider,” whether that be the grid or a wind-electric system, at the AC breaker panel, also known as the mains panel, breakers box, or fuse box. This box or panel is often located on the wall in a basement, garage, or outside the structure. It has a bunch of breakers that are all labeled and help provide power to different places in the home. These breakers safeguard the building’s wiring against electrical fires while also allowing power to be removed for maintenance.

The inverter’s AC output is protected by a circuit breaker, much like the electricity in your house or workplace. This circuit breaker is often installed in the mains panel of the structure. In the event that maintenance on the inverter is required, it may be isolated from either the power grid or the loads it is powering. The electrical wiring inside the circuit is likewise protected by the breaker.

Electricity may be provided by an off-grid wind-electric system even when the wind isn’t blowing, thanks to the backup generator (sometimes known as an emergency backup, gas guzzler, or “the noise”). However, designing a system to account for the worst-case scenario, such as a few weeks of calm weather in the summer, might lead to a very big, costly system that is seldom utilized to its capacity and runs a massive surplus during windy periods. Use a minimum of two energy sources to keep your money in your wallet. Although wind-PV hybrid systems are a great match for local renewable resources, a backup, fuel-powered generator may still be required in certain cases.

Depending on the model, engine-generators run on biodiesel, petroleum diesel, gasoline, or propane. As most generators only provide alternating current (AC) power, a battery charger (either separate or built into an inverter) is required to convert this into the direct current (DC) used to power batteries. A well-designed renewable energy system should only need operating generators for 50–200 hours per year, despite the fact that they are noisy and emit a foul exhaust smell that is bad for the environment.

INSTALLATION

Assembly and construction, as well as electrical integration, are all required for wind turbine installation. Typical components of a project are:

  • Excavation
  • Foundations and concrete molds
  • Putting in Electrical Conduits
  • Construction of a Wind Turbine and Tower Mechanistically
  • Installation of the turbine, which requires the use of a crane or other towing vehicle.
  • Grid-tie connection and electrical installation of controllers/inverters
  • Building and electrical utility permitting/approvals
  • Commissioning/testing

We invite you to read: “Onshore Versus Offshore Wind Energy: Pros & Cons”


DIY Wind Energy

Conclusion

One Community will keep working on this website until all the specifics of a fully functional, repeatable system are detailed in text, video, and downloadable lessons. This will be done with the building of the Earthbag Village and the Duplicable City Center, with further modifications made throughout the growth and construction of the next six towns. In

FAQs

What are wind turbines made of?

The towers of wind turbines are often constructed from steel. Glass-fiber reinforced polyester or wood-epoxy are used to make the blades. Most current models include a matte coating, which significantly cuts down on glare.

How often do wind turbines produce electricity?

Depending on the wind speed, a contemporary wind turbine may generate power between 70 and 85 percent of the time.

Are wind turbines noisy?

Most newer, smaller wind turbines are built with silence in mind. Technology like gearbox-free direct-drive systems helps them accomplish this goal. These days, the wind itself is noisier than a wind turbine, and it’s quite improbable that noise will be audible from tiny wind turbines at heights more than fifty meters.

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