Definitions. As used in this section, the following terms shall have the meanings indicated:
AMBIENT SOUND LEVELThe all-encompassing sound at a given location, usually a composite of sounds from many sources near and far. For the purpose of this chapter, the "ambient sound level" shall mean the quiescent background level, that is, the quietest of ten-second average sound levels measured when there are no nearby or distinctly audible sound sources (e.g., dogs, cars in line-of-sight, or jets). Daytime ambient measurements should be made during mid-morning, weekday hours while nighttime measurements should be made after midnight.
AREA, CORNER SIDEThe area of a lot lying between the boundary of the corner side building elevation of the principal structure and the corner side lot line, unobstructed from the ground upward and unoccupied except by specific uses and structures allowed in such area of a lot as allowed elsewhere in the Zoning Ordinance.
AREA, FRONTThe area of a lot lying between the boundary of the predominant front building elevation of the principal structure and the front lot line, extended across the full width of the lot unobstructed from the ground upward and unoccupied except by specific uses and structures allowed in such area of a lot as allowed elsewhere in the Zoning Ordinance.
BUILDING MOUNTED WIND ENERGY SYSTEMS (BWES)A Wind Energy System that utilizes a monopole to structurally attach onto the roof of a building or to the side of a building. A BWES system may have a Horizontal Axis or Vertical Axis Wind Turbine system attached to generate the power.
DAYTIME HOURSThe hours of the day from 7:00 a.m. to 10:00 p.m., local time.
HEIGHT, WIND ENERGY SYSTEMThe vertical distance above the average grade of the adjacent ground to the highest point of travel of a WED, including the highest reach of the blades.
HORIZONTAL AXIS WIND TURBINE (HAWT)A turbine that rotates on a horizontal axis, typically with propeller blades. They have the main rotor shaft and generator at the top of the tower and must be pointed into the wind. Smaller turbines are pointed by a simple wind vane, while larger turbines generally use a wind sensor coupled with a servo motor. Most have a gearbox, which turns the slow rotation of the blades into a quicker rotation that is more suitable to drive an electrical generator.
LARGE WIND ENERGY SYSTEMS (LWES)A Wind Energy System with turbine towers and fully extended blades which primarily produce energy for its owner (affiliated business). A LWES may only include one Wind Energy System, electronic conversion, and distribution system.
NIGHTTIME HOURSThe time of the day after 10:01 p.m. until 6:59 a.m. local time.
OPERATIONAL CONDITIONWES facilities being capable of operating at full capacity while meeting all sound and other permit conditions.
OWNERThe person(s) who hold(s) title of the property on which a SWES facility is installed.
SHADOW FLICKERThe on-and-off strobe light effect caused by the shadow of moving blades cast by the sun passing above the turbine. Shadow flicker intensity is defined as the difference or variation in brightness at a given location in the presence and absence of a shadow.
SMALL WIND ENERGY SYSTEM (SWES)A Building Mounted Wind Energy System or Tower Mounted wind Energy System that is accessory to the principal use and intended to primarily reduce on-site consumption of utility power. SWES energy produced in excess of on-site consumption may be sold back to the utility power service provider. However, a wind energy system that primarily produces energy to be sold commercially shall be classified as a Large Wind Energy System.
SOUNDA disturbance or oscillation that propagates outwardly as acoustic waves through the air.
SOUND FREQUENCYThe number of oscillations per second expressed in hertz (Hz). High frequency sound has more oscillations per second, whereas low frequency sound has fewer. The types of frequencies include:
(c) LOW FREQUENCYSound with frequencies below 100 Hz, including audible sound and infrasound.
SOUND LEVELThe A-weighted sound pressure level in decibels {dB(A)} (or the C-weighted level {dB(C)}, if specified) as measured using a sound level meter that meets the requirements of a Type 2 or better precision instrument according to ANSI S1.4 must have an integrating feature that meets ANSI S1.43 and procedures must meet the applicable portions of ANSI S12.9. All sound measurements must be made when ground level winds are below six mph. The "average" sound level is time-averaged for a period of not less than one minute nor more than two minutes using an integrating sound level meter that meets the requirements of ANSI S1.43 or its latest revision.
SOUND PRESSURE LEVEL, A-WEIGHTED dB(A)The "weighted" scale that is most often utilized for the measurement of audible or tonal sound levels. These are sounds that range from 20 to 20,000 Hz and that the human ear can typically hear.
SOUND PRESSURE LEVEL, C-WEIGHTED dB(C)The "weighted" scale that is utilized especially for measurement of low frequency sound which included but is not limited to bass tones or infrasound and may or may not be audible to the human ear.
STRUCTURAL WEIGHT, WESThe combined weight of the tower, wind turbine generator, and any other component(s) otherwise supported by the base foundation.
SUN GLINTThe reflection of sunlight off a surface of the blades, tower, or other component of the wind energy system.
TOWER MOUNTED WIND ENERGY SYSTEM (TWES)A freestanding Wind Energy System that is mounted to the ground and structurally attached to a tower. A TWES system is typically less than 175 feet in height and may have a Horizontal Axis or Vertical Axis Wind Turbine system attached to it that generates the power.
TOWER, MONOPOLEA single pole structure that supports a wind turbine without the use of guy wires or similar support systems.
TURBINEThe parts of a WES including the blades, nacelle and tail.
USE, RESIDENTIALA use under any of the following major category groupings of the zoning ordinance; "agricultural uses" or "residential uses" or "business uses" or "industrial uses."
VERTICAL AXIS WIND TURBINE (VAWT)A turbine in which the main rotor shaft is arranged vertically creating an "eggbeater" appearance. The generator and gearbox are located near the ground, so the tower does not have to support it and it is more accessible for maintenance. This definition includes reference to an illustration of a VAWT for explanatory but not limiting purposes.
WATT(Symbol: W) A derived unit of power in the International System of Units (SI). It measures rate of energy conversion. One watt is equivalent to 1 joule (J) of energy per second. The kilowatt (symbol: kW) is equal to 1,000 watts. The megawatt (symbol: MW) is equal to one million watts.
WIND ENERGY SYSTEM (WES)A wind energy production, conversion and distribution system generally consisting of a wind turbine tower and associated electronic equipment.
WIND FARMMore than one Large Wind Energy Systems (LWES) on a given site, constructed for the commercial generation (or sale) of electrical power. For the purposes of this chapter, more than one Small Wind Energy System (SWES) which is constructed for commercial generation (or sale) of electrical power shall be considered a wind farm.