Similar to other land uses, a county may choose to identify which zones or regions within the county that wind energy conversion systems are allowed. Generally commercial-scale wind turbines need to be sited in locations that provide access to a good quality wind resource, which are typically found in open areas away from buildings or other obstructions.
Permitting regulations in this category address the internal spacing between wind turbines in a given project. There may be a variety of reasons for this type of regulation including ensuring one turbine will not damage another if it malfunctions, or to mitigate impacts on migratory birds and bats. Many developers will already include such internal spacing in their project plans to ensure that each turbine has sufficient wind resource availability since there are significant costs and considerations with decommissioning a project if it is unsuccessful.
Some counties require signs for safety reasons in their permitting regulations, while some also regulate what type of non-safety related signs are allowed. Many ordinances require wind projects to comply with the National Electric Code which already requires high-voltage warnings if necessary, and posting of emergency contact information.
As wind energy technology and project siting practices have advanced, the interference with radio, television, cellular, and other broadcast services has been minimized. However local ordinances may require a study of potential impacts to broadcasting services prior to receiving a permit or a listing of such broadcast towers within a certain radius.
Setbacks refer to permitting regulations for the distance from homes and property lines. A county may impose setbacks for a variety of reasons and the requirements may vary depending on the specific land uses. Many setbacks are established generally to protect the available wind resource to encourage wind development while also addressing concerns of homeowners and community members regarding noise, safety, and aesthetics.
Most, if not all, county permits for wind energy conversion systems are conditional use permits. Often the permitting authority will establish threshold requirements, as seen with the ordinances in the County Wind Ordinance Survey.
Wind turbine noise and associated impacts are some of the more important issues facing local authorities in permitting wind projects. Regulations in this category generally refer to a decibel measurement of the sound emissions from a turbine, and increasingly local authorities are asked to consider the concerns of the community in setting these regulations. Many Minnesota counties refer to the state noise standards, while some impose additional requirements and measurements on the appropriate levels of sound from wind turbines in their community.
Commercial wind turbines are installed on tall towers and proper lighting is required for the safety of any nearby aviation facilities. There are also concerns with the impacts different lighting mechanisms may have on local communities and wildlife. All wind projects must comply with any applicable Federal Aviation Administration (FAA) requirements regarding appropriate lighting, and many county permitting regulations refer to or incorporate those requirements.
Permitting regulations in this category refer to the maximum total height of a wind turbine allowed. Current wind turbine designs are the result of many years of research and development in establishing the ideal height of the tower and blade lengths in order to most efficiently capture the wind resource. Counties may chose to regulate in this category for a variety of reasons, including public safety or aesthetics.
These permitting regulations address the feeder lines and communications lines used to connect the wind turbines to the other project infrastructure, in order to minimize the visual impact from these components. Currently, the common industry practice currently is to bury these electric lines; however there may be certain geological conditions that make burying these lines impractical.