Environmental impact of wind power

[14][15][16] A report by the Mountaineering Council of Scotland concluded that wind farms harmed tourism in areas known for natural landscapes and panoramic views.

[39] A typical study of a wind farm's Life cycle assessment, when not connected to the electric grid, usually results in similar findings as the following 2006 analysis of 3 installations in the US Midwest, where the carbon dioxide (CO2) emissions of wind power ranged from 14 to 33 tonnes (15 to 36 short tons) per GWh (14–33 gCO2/kWh) of energy produced, with most of the CO2 emission intensity coming from producing steel, concrete, and plastic/fiberglass composites for the turbine structure and foundation.

[40][41] By combining similar data from numerous individual studies in a meta-analysis, the median global warming potential for wind power was found to be 11–12 g CO2/kWh and unlikely to change significantly.

[52] The Kleinman Center for Energy Policy at the University of Pennsylvania (May 2021) reports that neodymium, a critical rare-earth element, is used in manufacturing permanent magnets for wind turbines, which helps improve their efficiency and reduce maintenance needs.

The extraction of REEs, expected to double in demand by 2035 due to renewable energy needs, presents environmental risks, including radioactive waste.

Sustainable mining practices, supply diversification, and recycling innovations are being considered to manage the increased demand and environmental risks associated with REE production.

[57] Other options for disposing of the blades includes incinerating the material or grinding it up into powder, but both of these methods are not only expensive, but also inefficient and involves additional energy usage.

[58] Blade incineration emits a significant[need quotation to verify] amount of green house gases, though it can be used as a source of heat and power, which somewhat offsets these emissions.

[59][60] Because of their hollow design for less weight, blades can take up an enormous volume compared to their mass, making road transport difficult, expensive, and dangerous due to wide turning berths, extra safety vehicles, and longer flatbed trucks.

Other recycling methods include creating pellets for waterproof boards and injectable plastics, as well as pyrolysis for producing paints, glues, and both cement and concrete.

[74] Research indicates that turbine blades could successfully be repurposed as electrical transmission poles as their strength and structural stability was found to be comparable to the materials that are typically used.

[77] Overall, there are several different avenues through which wind turbine components can be recycled, reused, or repurposed, all with their advantages and disadvantages, and there continues to be research conducted to determine even more ways that the materials can be economically used.

[78] In addition to carbon fiber blades sometimes being installed due to lower weight and higher strength and durability compared to fiberglass-epoxy composites, there are wind turbines with a modular wooden structural support trunk, which is stronger, lighter, easier to recycle and transport, and more carbon-neutral than steel.

The vegetation clearing and ground disturbance required for wind farms are minimal compared with coal mines and coal-fired power stations.

[102][103] Environmental assessments are routinely carried out for wind farm proposals, and potential impacts on the local environment (e.g. plants, animals, soils) are evaluated.

More specifically, it suggests: Wind turbines, like many other human activities and buildings, also increase the death rate of avian creatures such as birds and bats.

[141] To combat this phenomenon, ultrasonic deterrents have been tested on select wind turbines and has been shown to reduce bat fatalities from collision and barotrauma.

[141] A 2013 study produced an estimate that wind turbines killed more than 600,000 bats in the U.S. the previous year, with the greatest mortality occurring in the Appalachian Mountains.

[142] Mortality, specifically in migratory birds and bats, seems to be increased in locations where wind patterns seem to facilitate both migration paths and energy production.

Blue Mussels also reduce turbidity in the ocean water, making for greater underwater visibility, and leave behind their shells as shelter, further altering possible inhabitants of their coastal domain.

Turbulence from spinning wind turbine rotors increases vertical mixing of heat and water vapor that affects the meteorological conditions downwind, including rainfall.

[166] Renewable energy commercialization led to an increasing industrial image of wind power, which is being criticized by various stakeholders in the planning process, including nature protection associations.

[178][179][180] A 2014 study by Health Canada[181] involving 1238 households (representing 79 percent of the households in the geographic area studied) and 4000 hours of testing in Ontario and on Prince Edward Island includes the following supportive statements of wind turbine low frequency noise annoyance in its summary: "Wind turbines emit low frequency noise, which can enter the home with little or no reduction in energy, potentially resulting in...

Common environmental concerns associated with offshore wind developments include:[183] Germany restricts underwater noise during pile driving to less than 160 dB.

[185] During construction, heavy equipment generates noise and vibrations that are very well conducted through water and impacting marine life, such as harbour porpoise which rely on sound for navigation underwater.

In 2009, a comprehensive government environmental study of coastal waters in the United Kingdom concluded that there is scope for between 5,000 and 7,000 offshore wind turbines to be installed without an adverse impact on the marine environment.

[187][188] A study published in 2014 suggests that some seals prefer to hunt near turbines, likely due to the laid stones functioning as artificial reefs which attract invertebrates and fish.

The pile-driving construction process is an environmental concern as the noise produced is loud and propagates far in the water, even after mitigation strategies such as bubble shields, slow start, and acoustic cladding.

[183][need quotation to verify] Tripod fixed bottom foundations are used in transitional depth applications (20–80 m) and consist of three legs connecting to a central shaft that supports the turbine base.

[183] Gravity foundations are used in shallow depth applications (0–30 m) and consist of a large and heavy base constructed of steel or concrete to rest on the seabed.