Debunking common misconceptions about wind power project development

Myth 1: Wind turbines cause disruption for nearby residents and lower property prices

According to ADEME (the French Agency for Ecological Transition), the operation of wind turbines generates ambient noise composed mainly of low frequencies, between 20 and 100 Hz. The sound intensity reaches approximately 100 decibels at the rotor, decreases to 55 decibels at the base of the installation, and drops to nearly 35 decibels at a distance of 500 meters. For reference, the sound level perceived at this distance is comparable to that of a quiet conversation, while a busy road produces approximately 55 decibels.

To limit potential nuisances for local residents, regulations require that wind turbines be located at least 500 meters from dwellings. This minimum distance may be increased by the prefect during the review of the application, before the project authorization is granted.

Numerous studies have examined the influence of wind farms on the real estate market and generally conclude that they have a very limited, or even negligible, effect on property values. This type of assessment remains complex, as it is necessary to distinguish the specific impact of wind turbines from a multitude of economic and territorial parameters. Several studies show that their presence does not alter local real estate dynamics. A study conducted in 2010 in the Hauts-de-France region, in particular, observed an increase in the number of transactions for building plots in areas hosting two wind farms, without a decrease in the price per square meter.

Myth 2: Wind turbines cause damage to the environment where they are located.

Onshore wind farms are mostly located in agricultural or already developed areas, which limits their impact on sensitive natural environments.

To limit this impact, studies must be conducted before wind farms are installed. This ensures they can never be located on major bird migration routes or in the nesting areas of protected species. There are also bird deterrent systems and methods for protecting bats.

A study conducted by the League for the Protection of Birds (LPO), based on the analysis of 1.065 wind turbines, estimates bird mortality at approximately six to seven birds per year per turbine. This figure, while limited, remains a cause for concern.

By comparison, a 2009 study of 75 sites in Manhattan found that in the United States, 32 birds die every second after colliding with buildings or skyscrapers. Glass facades are therefore the second leading cause of bird mortality, just after habitat destruction.

Another major, often underestimated factor is the intensification of agriculture. It is considered the primary cause of the decline in bird populations in Europe, ahead of climate change, urbanization, and the transformation of forest areas. These pressures alone are estimated to have led to the disappearance of nearly 800 million birds in the space of forty years on the European continent.

Finally, when compared to the energy produced, the wind power sector is associated with approximately 0,3 deaths per gigawatt-hour, compared to nearly 5,2 deaths per gigawatt-hour for power plants operating on fossil fuels, highlighting an overall much smaller impact.

At sea, wind turbines rest on metal structures anchored to the seabed and connected by cables protected by riprap and layers of concrete placed underwater. This type of installation does indeed involve the artificial alteration of the seabed, which can lead to the disappearance of certain habitats and affect local species.

However, their long-term impact on the seabed should be put into perspective, as observed in Belgium at wind farms that have been operating for over a decade. The foundations of some offshore wind turbines could even become reservoirs of biodiversity.

Myth 3: Wind energy is intermittent and therefore unreliable

Like solar power, wind power is an energy source whose production varies, as it depends directly on weather conditions. According to ADEME, wind turbines are currently operational between 75% and 95% of the time.

Recent technologies, however, make it possible to optimize their performance. New equipment takes advantage of wind forecasts developed by Météo-France to adjust its operation, while electricity storage devices are gradually being developed to store the surplus energy produced during periods of strong winds.

In practice, a wind turbine does not operate at full power continuously: its rotation speed adjusts to the wind strength. Over a full year, the amount of electricity produced corresponds to operating at maximum power for approximately 20 to 25% of the time, a figure that can reach 40% for offshore wind farms.

This ratio corresponds to the "load factor," which should not be confused with the actual annual operating time. The latter, between 75% and 95%, depends heavily on the characteristics of the site: terrain, environment (wooded, urban or agricultural areas), proximity to bodies of water, coastline, ridges or hills.

Myth 4: Wind turbines are very expensive

The results of the latest tender, organised in November 2020, indicate a weighted average cost of €59,5/MWh for the selected projects, confirming a gradual decrease in prices compared to previous years.

Moreover, the buyback price of electricity from wind power is lower than the market price, which was around €64/MWh on July 5, 2021. At that time, wind power did not generate any additional burden on public finances, as the market price was higher than the tariffs from the latest tenders.

Beyond production costs, wind farms also contribute to the economic vitality of local areas. They help increase land value, develop and maintain road infrastructure, and generate tax revenue for local communities. An onshore wind farm can thus generate between €10.000 and €12.000 in annual revenue per megawatt installed for local authorities.

Myth 5: Wind turbines have a negative impact on human health

From a health perspective, some critics suggest that wind turbines may have harmful effects on livestock. However, according to the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), no scientific link has been established between the presence of wind turbines and any health problems observed in farm animals. To date, only two isolated cases have been recorded in Europe.

Similarly, infrasound—sound waves imperceptible to the human ear—is sometimes accused of causing a supposed "wind turbine syndrome," characterized by nausea, headaches, and vomiting. Here again, several studies conducted by ANSES (the French Agency for Food, Environmental and Occupational Health & Safety) and Finnish authorities have not established a correlation between these low frequencies and harm to human health. Research conducted in New Zealand even highlighted a so-called "nocebo" effect: those who reported being bothered were primarily those who had previously believed in the harmfulness of wind turbines.

Myth 6: Wind turbines cannot be recycled

During the dismantling of a wind turbine, the concrete foundations are crushed and then sorted. The resulting materials can then be reused as aggregates in new concrete, including for the construction of other wind turbine infrastructure. A decree dated June 22, 2020, published in the Official Journal on June 30, now mandates the complete removal of the foundations, except when an environmental assessment demonstrates that such an operation would be detrimental.

The proportion of concrete that can actually be reused depends on several parameters, such as the quality of the recovered material, its composition, applicable standards, and the specific constraints of each project. wind power projectIn practice, recycled concrete can replace some of the natural aggregates, with substitution rates generally between 20% and 60%.

Overall, nearly 90% of a wind turbine's components are recyclable. However, some elements remain more complex to recycle, particularly the blades, due to the composite materials they contain. It is also true that materials like steel and concrete, although recyclable, are among the world's largest emitters of CO₂, each accounting for approximately 7% of global emissions.

Despite these limitations, the carbon footprint of wind power remains significantly more favorable than that of fossil fuels. According to ADEME (the French Agency for Ecological Transition), onshore wind power generates an average of 12,7 g of CO₂ per kilowatt-hour produced, and offshore wind power 14,8 g. By comparison, electricity production from fossil gas emits approximately 490 g of CO₂ per kWh, and that from coal nearly 820 g per kWh.

Illustrative image of the article via Depositphotos.com.