(A) Zoning districts. Residential wind turbines in accordance with the standards in this section are prohibited in the R-1 (Single Family Residential District), R-2 (Multiple Family Residence), C-1 (Downtown Commercial District), C-2 (Service-Commercial), R-3 (Mixed Use Residence), PUD (Planned Unit Development), R-1M (Modular and Mobile Home) unless they are structurally attached to the principal structure (roof) and do not exceed 5 feet in height from the roof peak, which then would be deemed permitted accessory uses. Residential and small wind turbines are a permitted accessory use on lots at least 20 acres in size in the A-1 (Agriculture-Conservation), I-1 (Light Industrial), and I-2 (General Industry). Utility wind turbines are a permitted accessory use on lots at least 40 acres in size in the A-1 (Agriculture- Conservation). Wind energy systems are not permitted in any other zoning districts.
(B) Standards.
(1) Number. No more than one wind energy system is permitted per parcel.
(2) Height. The total height of the tower, including any portion of the rotor or axis extending above the tower, shall not exceed the horizontal distance between the base of the tower and the nearest lot line or building line, except that the horizontal distance may extend beyond the nearest lot line or building line, provided there are no overhead utility lines or easements therefore or if the abutting areas is a public alleyway. Furthermore, the City Council may allow the height requirements to be exceeded upon recommendation of the Planning and Zoning Commission, provided it is satisfied that the proposed structure will withstand the windloads in the area. As evidence of this, the City Council shall require the following information:
(a) Dimensional representation of the various structural components of the tower construction, including the base and footings.
(b) Design data which shall indicate basis of design, including manufacturer’s dimensional drawings and installation and operation instructions.
(c) Certification by an independent registered professional engineer or other qualified professional that the structure is sufficient to withstand windload requirements for structures as established by the applicable building construction codes.
(3) Blade length. For residential wind turbines, other than roof-mounted wind turbines, a maximum blade length of 15 feet is permitted.
(4) Roof mounting. Roof-mounted wind turbines are not permitted, except those that do not exceed 5 feet in height or length.
(5) Setbacks.
(a) For residential wind turbines, the base of the wind turbine tower shall be set back from all property lines a distance equal to the hub height. Wind energy systems shall not be installed in the front yard of any lot or in the side yard of a comer lot adjacent to a public right-of-way.
(b) For small wind turbines, the base of the wind turbine tower shall be set back from all property lines a distance equal to the hub height. In addition, the base of the wind turbine tower shall be set back from the nearest public right-of-way, above ground power line, drainage or utility easement, recreational field, dwelling, school, business or other habitable structure, 300 feet or 1.5 times the total height, whichever is greater.
(c) For utility wind turbines, the base of the wind turbine tower shall be set back from all property lines a distance equal to the hub height. In addition, the base of the wind turbine tower shall be set back from the nearest public right-of-way, above ground power line, drainage or utility easement, recreational field, dwelling, school, business or other habitable structure, 600 feet or 3.0 times the total height, whichever is greater.
(6) Easements. Wind energy systems shall not encroach on public drainage and utility easements, utility roadway or trail easements, or any other public easements.
(7) Noise. Wind energy systems shall comply with Minnesota Pollution Control Agency standards outlined in Minn. Rules Chapter 7030, as amended, and city code at all property lines.
(9) Aesthetics. All portions of the wind energy system shall be a nonreflective, non-obtrusive color, subject to the approval of the Community Development Director. Only monopole towers are permitted. The appearance of the turbine, tower and any other related components shall be maintained throughout the life of the wind energy system pursuant to industry standards. Systems shall not be used for displaying any advertising. Systems shall not be illuminated.
(10) Feeder lines. The electrical collection system shall be placed underground within the interior of each parcel. The collection system may be placed overhead near substations or points of interconnection to the electric grid.
(11) Vibration. No wind energy system shall produce vibrations through the ground that are humanly perceptible beyond the property on which it is located.
(C) Safety.
(1) Standards and certification.
(a) Standards. Wind energy systems shall meet minimum standards such as International Electrotechnical Commission (IEC) 61400-2 or the American Wind Energy Association’s (AWEA) Small Wind Turbine Performance and Safety Standard or other standards as determined by the city’s electrical engineer.
(b) Certification. Wind energy systems shall be certified by Underwriters Laboratories, Inc. and the National Renewable Energy Laboratory, the Small Wind Certification Council or other body as determined by the Community Development Director for conformance to applicable standards. The city reserves the right to deny a building permit for proposed wind energy systems deemed to have inadequate certification or testing for operation in a severe winter climate.
(c) Maintenance. Wind energy systems shall be maintained under an agreement or contract by the manufacturer or other qualified entity.
(d) Utility connection. All grid connected systems shall have a completed written agreement with the local utility prior to the issuance of a building permit. A visible manual external disconnect must be provided, which complies with applicable electric codes.
(e) Abandonment. If the wind energy system remains nonfunctional or inoperative for a continuous period of one year, the system shall be deemed to be abandoned and shall constitute a public nuisance. The owner shall remove the abandoned system at their expense after a demolition permit has been obtained. Removal includes the entire structure including foundations to below natural grade and transmission equipment.
(f) Permits. Those permits as required, and a conditional use permit if required, shall be obtained for any wind energy system prior to installation.
(g) Liability insurance. No building permit shall be issued for the construction of a wind energy system until and unless the applicant for the building permit deposits with the Zoning Administrator a policy of liability insurance indemnifying the applicant from liability for personal injury or property damage arising from the operation, malfunction, or collapse of the wind energy system in the sum of at least $1,000,000. The insurance policy so deposited shall contain a clause obligating the company issuing the same to give at least 10 days’ written notice to the city before the cancellation thereof, the conditional use permit to be automatically revoked upon the lapse or termination of said insurance policy.
(Ord. 547, passed 9-27-2011) Penalty, see § 10.99