Generally, a wind turbine generates around 50 decibels of sound pressure.
As the typical distance of the nearest house from a wind turbine is 300 meters, the sound level will be as low as 43 decibels at that distance.
Read the following article to learn more about the noise levels of different turbines and how engineers work to reduce them.
How far away can you hear wind turbines?
You will hear wind turbine noise at a distance of 4 kilometers if you do not consider other noises in the environment. It is possible at night time as noise level at night is minimal.
A wind turbine is known for its low-noise power generation. After the photovoltaic solar panels, the wind turbine is the most chosen energy cultivation method for isolated regions from the national power grid.
However, though wind turbines are one of the least noisy power generators, it still creates sound pressure. Thus, how far should you put your wind turbine for minimal noise? Let’s find out.
For our estimation, we can use nighttime, as at night, the environment is the least noisy. Thus, the noise from the wind turbine will travel further than the average distance.
Check the table below to know at which distance how much sound pressure will be for a wind turbine:
| Distance from the wind turbine in meters | Level of sound pressure in decibels |
| 0 | 50 |
| 300 | 43 |
| 500 | 38 |
| 1000 | 20 |
| 3500 | 7.5 |
How to reduce noise from wind turbines?
Several options come into play when it comes to reducing wind turbine noise.
Before you learn how to reduce wind turbine noise, you need to know what parts of a wind turbine create noise. There are two primary sources from which noise is generated in a wind turbine, including mechanical and aerodynamic parts.
You can take several measures to ensure that you have a low-noise wind turbine. First of all, you can use upwind rotors for better noise reduction. Rotor blades create a thumping sound if not facing toward the wind’s direction.
Therefore, just use an upwind rotor, and it will automatically face the direction of the wind. However, today all companies are giving upwind rotors with their wind turbines.
Besides, the aerodynamic casing of the turbine behind the rotor will pass the wind around the casing smoothly without any jerking or shaking.
Moreover, the mechanical parts, such as shafts, gears, generators, etc., make noise if it is not well-tuned. Also, vibration isolation is required for these parts to operate, and for these dampers can be used.
How noisy are vertical wind turbines?
Vertical wind turbines create noise with a sound pressure level of 38 to 40 decibels when wind velocity is around 10 meters per second.
It makes vertical of wind turbine the quietest wind turbine among the types.
Two types of wind turbines are available, including horizontal wind turbines and vertical wind turbines. Most people are familiar with the horizontal wind turbine, which is not as quiet as the vertical one.
Currently, most first-world countries are utilizing vertical wind turbines by placing them in the middle of the highways. As a result, whenever a vehicle passes by, wind turbines rotate and generate electricity.
As vertical wind turbines are quieter than vertical ones, you can use these near the residential area. Besides, these are not as tall as the horizontal ones as well. As a result, there is less material cost.
Which turbine is the noisiest?
If it is about wind turbines, the horizontal wind turbine is the noisier one. It makes slightly higher sound pressure than the vertical wind turbine.
However, when it comes to all the turbines, such as gas turbines, steam turbines, hydroelectric turbines, etc., steam turbines are the noisiest ones.
A steam turbine creates around 88 to 90 decibels of sound pressure, double the sound a wind turbine makes. On the other hand, a gas turbine generates an estimated 85 decibels of sound.
In either case, the wind turbine is the best solution when it comes to sound pollution.
Sources:
- https://www.ge.com/news/reports/how-loud-is-a-wind-turbine# – Loudness of wind turbine (General Electric)
- https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-10-78?trk=public_post_comment-text – Wind turbine sound pressure (BMC – Springer)
- https://windexchange.energy.gov/projects/sound# – Wind turbine noise traveling distance (Wind Exchange)
- https://www.hacacoustics.global/news/how-to-reduce-wind-farm-noise/ – Noise reduction in a wind turbine (Hodgson Acoustics)
