Future Wind Turbines to be More Powerful and Cause Less Sound Pollution: Study
Wind turbines are likely to be 60% taller than those installed until 2020
Upcoming wind turbines are expected to generate significantly more power compared to their predecessors while also causing less noise pollution in the surrounding areas, according to a recent study conducted by the Lawrence Berkeley National Laboratory (Berkeley Lab).
The study titled “Effects of land-based wind turbine upsizing on community sound levels and power and energy density” simulated the development of 22 distinct wind energy projects at two typical locations, using eleven different models of wind turbines.
The study aimed to determine the output, nameplate capacity, number of turbines, and receptor sound level patterns of wind projects using older, current, and future turbine models, all situated within a fixed land area.
Future of Wind Turbines
One of the most significant changes is the scaling of wind turbines, with taller and larger turbines being deployed and predicted to continue in the future.
Although these larger turbines are more powerful and efficient, they are also expected to generate higher sound emissions than the ones installed in the last decade.
According to the Berkeley Lab analysis, future wind turbines are expected to be more than 60% taller than the ones most installed in the United States between 2011 and 2020.
Due to their larger size, fewer turbines can fit in the same land area, resulting in a 60% reduction in the average number of turbines.
Despite this decrease in the number of turbines, the projects using future turbines will have higher installed capacities and estimated annual energy output for a given land area, increasing by roughly 11% and 60%, respectively.
Furthermore, despite the future turbines being louder than their predecessors, community sound levels are expected to decrease by 18% due to increased setbacks from homes and fewer wind turbines being constructed in the same land area.
This decrease in sound levels is also aided by using serrated trailing edges on the blades of all future turbine models, which reduce sound levels by approximately 1.5 dBA.
Figure 1: Percent Change from Then
According to the research, lower sound levels are expected not only for homes neighboring wind projects but also for those located very close to the turbines on parcels hosting them.
The study found that average estimated receptor sound pressure levels surrounding the projects in all periods consistently decreased from those estimated in the ‘Then’ period.
The reduction in sound pressure levels is particularly significant in the ‘Future’ period, where decreases range from 1.5 to 3 dB.
Despite being closer to wind turbines and subject to higher noise limits, participating homes located on parcels where turbines can be hosted also experience a reduction in sound pressure levels in all periods, along with their non-participating neighbors.
Figure 2: Change in Sound Level from Then (dB)
Benefits of Future Turbines
Adopting taller and higher-capacity wind turbines in the future is expected to bring various benefits.
First, the turbines will be located further away from homes and property lines due to required setbacks based on their total height.
Second, fewer turbines could allow for more flexibility in their placement, potentially avoiding sensitive viewsheds.
Third, higher project capacities and output could lead to greater local economic benefits such as increased tax revenue and income.
According to an earlier report published by the lab titled ‘Land-Based Wind Market Report, 2022,’ the U.S. added 13.4 GW of wind power capacity in 2021, with nearly $20 billion of investments in new wind projects during the year.
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