Environmental issues associated with wind turbines

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[...] Environmental issues associated with wind turbines Sources : Environmental issues associated with wind energy - A review, Dai et al Wind energy: Increasing deployment, rising environmental concerns, Tabassum-Abbasi et al Impact on animals and wildlife Birds Collisions : several factors Turbine size/blade design Number/position Weather/lighting/topography Abundance of flying animals Species of flying animals Bats Pressure drop near turbine edges Attracted by ultrasounds & lights Treat turbines as trees Death rate grows exponentially with turbine height Marine species Disturbance No more access to natural habitats Change of flight/migration routes Important issues which can damage eco-systems at major scales Main issue : construction & maintenance Artificial reef effect : Anchored turbines act as reefs and increase abundance of fish Impact on animals and wildlife Mitigation Lack of data : need for close monitoring of wildlife International cooperation Use of modern tools : Computer modelling and simulation, video, radar, acoustic and thermal imaging Strategies Site selection Visibility Construction Structural improvements Innovative devices Visual impact and Shadow flickering Visual Impact “Turbines can be seen from as far as 30km” Shadow flickering Subjective & Difficult to quantify Increases with the turbine's height and wind farm's size Generated by the blade's rotation Shadow of a 22m turbine can be seen up to 5km Impact depends on the frequency blades/s) & Contrast NIMBY syndrome: opposition if the wind farm is close to where people live Aspects to quantify the impact: Perception of usefulness Intrusiveness (touristic landscapes, local topography) People mindset (support renewable energy?) Turbine design (white blades) & Farm Layout (regular) Visualization tools Mitigation Early local residents' involvement Visual impact assessment Fewer number of turbines Away from houses Public preferences in direct conflict with wind power developers' interest Impact on land: degradation and conflicts of use Soil degradation Land use Wind farms cause irrigation issues for agriculture Construction enhances soil erosion Excavation, heavy foundation, road construction fragilize soil Wastewater and oil in the soil Regions that are already fragile due to wind 1 onshore 3MW wind turbine requires a 40mx40m parcel Water-loss and evaporation enhancement make agriculture costly and technically difficult around wind turbines Mitigation Need to replant grass and trees after construction Prioritize human labor April in Indiana : a farmer friend who signed a contract with a wind developer and now wants out of his contract after seeing the erosion around the turbines and access roads. [...]

[...] Impact on climate: wind farms can modify local climate Measure Theory BEM, vortex wake, CFD, GCM Disturbance in the movement of air masses and exchange of energy, between atmosphere and ground, due to 2 factors : Wind is slowed down Turbulence is created LST difference between 2010 and 2003 Zhou et al +0.72°C / decade Mitigation Simulation Avoid creating turbulence in the wake : blade and rotor design Build wind farms where there is natural high turbulence “Using wind turbines to meet 10% or more of global energy demand in 2100 could cause surface warming exceeding 1°C over land installations.” Wang and Prinn Impact on climate: the carbon footprint of a wind turbine Wide range of emission factors Life-cycle analysis From 7.9 to 123.7 gCO2eq/kWh Depends on : ● Turbine design ● Materials ● Place ● Scope and assumptions What about recycling wind turbines ? [...]