TITLE VI PHYSICAL ENVIRONMENT
CHAPTER 15 SMALL WIND ENERGY CONVERSION SYSTEMS
6-15-1
6-15-2
6-15-3
Intent
Definitions
Permit Required
6-15-4 Technical Standards
6-15-5 Public Notification
6-15-1 INTENT. The intent of this ordinance is to balance the need for clean, renewable energy
resources as a necessity to protect the public health and safety of the community. The City of
Hopkinton, Iowa, believes these regulations are necessary to ensure the Small Wind Energy
Conversion Systems are appropriately designed, sited, and installed.
6-15-2 DEFINTIONS.
1.
Height, Total System. The height above grade of the system, including the
generating unit and the highest vertical extension of any blades or rotors.
2.
Small Wind Energy Conversion System (SWECS). A wind energy conversion
system which has a nameplate rated capacity of up to twenty (20) kilowatts for residential uses
and up to one hundred (100) kilowatts for commercial and industrial uses and which is incidental
and subordinate to a principal use on the same parcel. A system is considered a SWECS only if it
supplies electrical power solely for use by the owner on the site, except that when a parcel on
which the system is installed also receives electrical power supplied by a utility company, excess
electrical power generated and not presently needed by the owner for on site use may be used by
the utility company in accordance with section 199, chapter 15.11(5) of the Iowa Administrative
Code, as amended from time to time.
3.
Small Wind Energy Conversion System, Free Standing. A SWECS which is
elevated by means of a monopole tower only and is not located on another supporting structure
except that the tower shall have an appropriately constructed concrete base. Guyed, lattic, or
other non-monopole style towers shall not meet this definition.
4.
Small Wind Energy Conversion System, Horizontal Axis. A small wind energy
conversion system that has blades which rotate through a horizontal plane.
5.
Small Wind Energy Conversion System, Vertical Axis. A small wind energy
conversion system that has blades which rotate through a vertical plane.
6.
Tower. The vertical component of a wind energy conversion system that elevates
the wind turbine generator and attached blades above the ground.
7.
Wind Turbine Generator. The component of a wind energy conversion system
that transforms mechanical energy from the wind into electrical energy.
8.
Shadow Flicker. Alternating changes in light intensity caused by the moving
blade of a wind power generator casting shadows on the ground and stationary objects such as
the window of a dwelling.
6-15-3 PERMIT REQUIRED. It shall be unlawful to construct, erect, install or located in
SWECS within the City unless a permit has been obtained from the City Council. The permit
may be revoked by resolution by the City Council at any time if the purpose does not comply
with the rules or conditions set forth in this chapter or conditions imposed by the City Council.
The owner/operator of the SWECS must also obtain any other permits required by other federal,
state and local agencies/departments prior to constructing the system.
6-15-4 TECHNICAL REQUIREMENTS.
1.
Compliance with Federal Aviation Administration Regulations (FAA). No small
wind energy system shall be constructed, altered, or maintained so as to project above any of the
imaginary airspace surfaces described in FAR Part 77 of the FAA guidance on airspace
protection.
2.
Safety. Any climbing foot pegs or rungs below 15 feet of a freestanding tower
shall be removed to prevent unauthorized climbing. For lattice or guyed towers, sheets of metal
or wood may be fastened to the bottom tower section such that it cannot readily be climbed.
Tower base shall be fenced at least ten feet (10’) with razor wire and locked gates.
3.
Sound. Sound produced by the small wind energy system under normal operating
conditions, as measured at the property line, shall: a) not produce sound at a level that would
constitute a nuisance; b) shall comply with any local ordinance regulating the volume of sound
as a nuisance; if applicable. Sound levels, however, may be exceeded during short-term events
out of anyone’s control, such as utility outages and/or severe wind storms.
4.
Compliance with National Electric Code. Building permit applications for small
wind energy systems shall be accompanied by a line drawing of the electrical components, as
supplied by the manufacturer, in sufficient detail to allow for a determination that the design and
manner of installation conforms to the state National Electric Code.
5.
Utility Notification. No small wind energy system shall be installed until
evidence has been given that the utility company has authorized interconnection of the small
wind energy system to its electric distribution or transmission, under an agreement approved by
and subject to regulation adopted by the Iowa Utilities Board. Properties not connected to the
public utility system shall be exempt from this requirement.
6.
Insurance. A person seeking a building permit to erect a small wind energy
system shall provide evidence, in the form of a certificate of insurance satisfactory to the City
showing general liability insurance coverage for the installation and operation of the system
under a standard homeowner's or standard business owner's insurance policy, separate and
distinct from any insurance requirements of a public utility.
7.
Abandonment. If a wind turbine is inoperable for six consecutive months, the
owner shall be notified that they must, within six months of receiving the notice, restore the
small wind energy system to operating condition. If the owner fails to restore the system to
operating condition within the six month time frame, it shall be considered abandoned and the
owner shall be required, at owner's expense, to remove the small wind energy system. A small
wind energy system that has been abandoned may be abated as a public nuisance.
8.
Signage.
No signs, other than appropriate warning signs, or standard
manufacturer's or installer's identification signage, shall be displayed on a wind generator, tower,
building, or other structure associated with a small wind energy system, subject to local sign
regulation, if any.
9.
Lighting. No illumination of the turbine or tower shall be allowed unless required
by the FAA or unless allowed by applicable ordinance.
10.
Color. Freestanding SWECS shall be neutral color such as white, sky blue or light
gray. Other colors may be allowed at the discretion of the City Council. The surface shall be
non-reflective.
11.
Setbacks. The minimum distance between any freestanding SWECS and any
property line shall be a distance that is equivalent to one hundred fifty percent (150%) of the
total system height. The setback shall be measured from the property line to the point of the
SWECS closest to the property line.
12.
Maximum Height. Height shall be measured from the ground to the top of the
tower, including the wind turbine generator and blades.
a.
For lots of two (2) acres, the maximum height shall be 65 feet.
b.
For lots of three (3) to seven (7) acres, the maximum height shall be 80
c.
For lots of more than seven (7) acres the maximum height shall be 100
feet.
feet.
13.
(2) acres.
Minimum Lot Size. The minimum lot size for a freestanding SWECS shall be two
14.
Clearance of Blade. No portion of a horizontal axis SWECS blade shall extend
within 30 feet of the ground. No portion of a vertical axis SWECS shall extend within 10 feet of
the ground. No blades may extend over parking areas, driveways or sidewalks. No blade may
extend within 20 feet of the nearest tree, structure or above ground utility facilities.
15.
Location.
a.
No part of a SWECS shall be located within or over drainage, utility or
other established easements.
b.
A freestanding SWECS shall be located entirely in the rear yard.
c.
A SWECS shall be located in compliance with the guidelines of applicable
Federal Aviation Administration (FAA) regulations as amended from time to time.
d.
No SWECS shall be constructed so that any part thereof can extend within
20 feet laterally of an overhead electrical power line (including secondary electrical service lines
or service drops). The setback from underground electric distribution lines shall be at least
twenty (20) feet.
16.
Shadow Flicker. A shadow flicker model demonstrates that shadow flicker shall
not fall on, or in, any existing residential structure. Shadow flicker expected to fall on a roadway
or a portion of a residentially zoned parcel may be acceptable if the flicker does not exceed thirty
(30) hours per year, and the flicker will fall more than one hundred feet (100') from an existing
residence; or the traffic volumes are less than five hundred (500) vehicles on the roadway. The
shadow flicker model shall:
a.
Map and describe within a one thousand foot (1,000') radius of the
proposed dispersed wind energy system, the topography, existing residences and location of their
windows, locations of other structures, wind speeds and directions, existing vegetation and
roadways. The model shall represent the most probable scenarios of wind constancy, sunshine
constancy, and wind directions and speed.
b.
Calculate the locations of shadow flicker caused by the proposed project
and the expected durations of the flicker at these locations, calculate the total number of hours
per year of flicker at all locations.
c.
Identify problem areas where shadow flicker will interfere with existing or
future residences and roadways and describe proposed mitigation measures, including, but not
limited to, a change in sitting of the wind energy conversion system, a change in the operation of
the wind energy conversion system, or grading or landscaping mitigation measures.
17.
Automatic Overspeed Controls. All wind energy conversion systems shall be
equipped with manual and automatic overspeed controls to limit the blade rotation speed to
within the design limits of the wind energy conversion system.
18.
prohibited.
Roof Mounted Systems. Roof mounted wind energy conversion systems are
19.
Feasibility of Site. Evidence from a qualified professional that the site is feasible
for a wind energy conversion system, or that covenants, easements and other assurances to
document sufficient wind to operate the wind energy conversion system have been obtained.
6-15-5 PUBLIC NOTIFICATION. Prior to a permit being issued, notice shall be sent not less
than seven (7) days and not more than twenty (20) days to all property owners within six
hundred feet (600') of the proposed wind energy conversion system. No Permit shall be granted
when sixty (60) percent of the resident real estate owners in said district within six hundred (600)
feet of the proposed building and occupancy object thereto, except by a three-fourths (3/4) vote
of all the members of the council.