The Environment & Wildlife
Although the electricity from wind turbines has very little environmental impact (if any), the installation itself may affect local flora and fauna. In certain cases, an installation may trigger the need for an environmental assessment.
In general, wind turbines are not a hazard to wildlife. Cattle are willing to graze next to them, and sufficient clearance between the blades and ground prevents injury to any land animal (including humans). In terms of avian wildlife, you may have heard reports that wind turbines can present a threat to birds and bats. It is true that birds can be injured or killed if they collide with the blades or the tower; and that their breeding, nesting and feeding habits could be disturbed. However, these impacts can be avoided with good siting, and there is little evidence that single installations or small clusters of small wind turbines kill birds in significant numbers. In fact, it has been shown that household pets, pesticides and glass-faced buildings kill far more birds than wind turbines do (see chart on the right; Source: Erickson, et.al, 2002. "Summary of Anthropogenic Causes of Bird Mortality"). For more information on the effects of small wind turbines on wildlife, see these publications from the US National Wind Coordinating Committee (NWCC).
By nature, local birds avoid wind turbines by flying around them, and migrating birds tend to fly well above small wind turbine height. As a ‘rule of thumb’, avoid siting a wind energy system in areas where birds concentrate, such as in wildlife refuges or shoreline feeding and nesting areas. The turbine and tower should also be designed to reduce perching and nesting opportunities. This is typically not a problem with smaller systems.