(A) Conditional use permit required. Only SWECS shall be allowed under any circumstances, and it shall be unlawful to construct, erect, install, alter or locate any SWECS within the city unless a conditional use permit has first been granted by the Board of Adjustment in accordance with § 160.63 and this section. As part of the application for a conditional use permit, the applicant shall submit the following evidence and documentation.
(1) Utility notification. The property owner shall show that the public electrical utility has been notified of the proposed installation of an interconnected customer-owned generator, or alternatively shall state in the application that the owner intends to operate the SWECS and principal use without connecting the SWECS and principal use of the lot, or any building or structure located thereon, to the public electrical utility’s distribution and transmission facilities (herein, “off-grid”).
(2) Utility interconnection. The property owner shall provide copy of an executed interconnection agreement to the city prior to the issuance of any permit for a SWECS, and the SWECS shall comply with the requirements for interconnection and operation as set forth by the public electrical utility and the Iowa Utilities Board, except in the case of an off-grid lot and SWECS.
(3) Feasibility study.
(a) Actual wind speeds shall be measured at the proposed site for a minimum of a three-month period for the specific SWECS design and mounting height at the proposed SWECS location. Said data together with resources available from the Iowa Energy Center or similar public source shall be used to calculate the projected annual electrical generation of the proposed SWECS based upon the average annual wind speed at the proposed SWECS site, and the percentage of the principal use’s annual electrical consumption that it may supply.
(b) The conditional use permit may be revoked by the Board at any time upon finding that a SWECS is not compliant with this Code or with any of the conditions stipulated or required by the Board in granting the conditional use permit.
(c) The property owner shall be responsible for obtaining and complying with all other permits that may be required by federal, state and local agencies or departments, prior to installing or operating any SWECS.
(B) Restricted to accessory use. A SWECS shall be allowed only as an accessory use and shall supply electrical power solely for consumption by the principal use on the lot, except that excess electrical power generated and not presently needed by the principal use may be sold to a public electrical utility company that provides electrical power to the principal use, in accordance with the Code of Iowa and § 199, Chapter 15.11(5) of the Iowa Administrative Code as they may be amended from time to time.
(C) Minimum lot size. The minimum lot size for a SWECS shall be one acre, regardless of zoning district or principal use of the lot, and regardless of whether the SWECS is free-standing or building-mounted.
(D) Performance standards.
(1) Minimum annual average wind speed. Measurements at the proposed site and the mounting height for the SWECS shall show that the actual annual average wind speed is reasonably expected to be greater than nine mph under the existing conditions, unless the specific SWECS design can be shown to function efficiently at a lower annual average wind speed.
(2) Number of SWECS on a lot.
(a) Residential use. Each residential lot shall be restricted to a maximum of one SWECS.
(b) Nonresidential use. Each nonresidential use shall be restricted to a maximum of one free-standing SWECS that is equal to or taller than the tallest existing principal building that is located on the lot, exclusive of towers, spires, penthouses or other architectural projections.
1. Additional roof-mounted SWECS, and free-standing SWECS that are shorter than said principal building, may be allowed provided that the total aggregate annual generating capacity rating of all SWECS shall not exceed the annual electrical consumption of the principal use.
2. For the purposes of this section, any lot that is legally used for both residential and commercial purposes shall be considered to be a commercial use.
(3) Location and clearance.
(a) All freestanding SWECS shall be restricted to the rear yard of the lot.
(b) No part of any SWECS shall encroach into or over any public easement, or any public utility easement that has been obtained for distribution lines, whether electrical, natural gas or telecommunications.
(c) The lowest point along the outer-most arc of the blades of a horizontal axis SWECS shall be a minimum of 30 feet above the highest ground elevation. No portion of the blades, rotor or other moving parts of a vertical axis SWECS shall be less than 15 feet above the highest ground elevation. No blades of any SWEC shall extend over any property line, walkway, parking space or driveway. All blades shall at all time, now or in the future, have a minimum clearance of 20 feet in all directions from all trees and other vegetation, structures and wires and other inanimate physical objects.
(4) Tower design. Any tower that is used for or is part of WECS shall be restricted to a monopole design that does not necessitate guy wires, ground anchors or other external supports, whether the WECS is free-standing or building-mounted. Lattice, guyed and all other types of towers are expressly prohibited
(5) General design.
(a) Safety.
1. Every SWECS shall be equipped with both automatic and manual braking, governing or feathering systems to prevent uncontrolled rotation, excessive speed of rotation and excessive pressure on the tower structure, rotor, blades and other SWECS parts or components. Every said automatic braking system shall also stop turbine rotation in the event of a power outage in order to prevent it from feeding electrical power into the grid.
2. Every SWECS shall be equipped with a clearly marked shut off switch for said manual system, that can be easily accessed by emergency, utility company, and maintenance personnel.
3. Every SWECS, and in particular the towers of free-standing SWECS, shall be designed and secured to prevent climbing or other access by unauthorized persons.
(b) Signs and lighting. No signs or other advertising of any kind, and no lighting of any kind, shall be installed on any portion of any SWECS regardless of zoning district the lot is located in.
(c) Color. Building-mounted SWECS shall match or otherwise blend with the color of the principal building on which it is mounted. Freestanding SWECS shall be painted a neutral, matt color such as white, light gray, sky blue or non-reflective neutral color that will blend with the sky or other background according to the circumstances.
(6) Engineering.
(a) Plans and specifications for all components of the SWECS, including but not limited to the foundation and structure, generator, rotor and blades, electrical components, utility interconnect and storage system if any, shall be prepared and certified by a qualified professional engineer who is licensed in the State of Iowa to be compliant with professional standards and all applicable regulations.
(b) No SWECS shall be mounted on or otherwise attached to any building unless a professional structural engineer who is licensed in the State of Iowa shall have first determined that installation and operation of the building-mounted SWECS will not cause damage to the structure, and that the SWECS will not be at risk of detaching from the structure under design conditions as stipulated by applicable codes.
(7) Installation, operation and maintenance. Installation shall conform to the manufacturer’s recommendations and all applicable codes. All electrical components shall meet recognized test standards. All parts and components of a SWECS shall at all times be maintained, operated, repaired and serviced in full accordance with all manufacturer’s specifications and recommended frequency and extent for maintenance and regular servicing, and in any additional times or extent that may be necessary to ensure that the SWECS does not at any time pose a known or potential safety hazard. Any and all damages shall be immediately repaired.
(8) Nuisances. No SWECS shall be allowed to emit or generate sound in excess of the maximum permitted sound levels allowed by the municipal code according to the time of day, location and other applicable factors. Shadow flicker shall not be allowed to fall onto an adjoining property. No SWECS shall be allowed to cause radio, television or electromagnetic interference, and its operation shall cease unless or until the property owner completely eliminates any and all of such interference.
(9) Easement, right or guarantee. The granting of a conditional use permit to allow a SWECS shall not be construed to grant any kind or extent of easement, right, guarantee or expectation as to the availability of wind power, now or in the future, whether over any public or private property and irrespective of the nature of any type or cause of blockage, obstruction, impairment or diminishment of the wind. The owner of the property on which a legal SWECS is located shall have the sole responsibility of acquiring any easements or other assurance or protection that the owner deems to be desirable or necessary.
(10) Abandonment and removal. Any SWECS that is inoperable or not fully functional for the majority of days within six consecutive months shall be deemed to be abandoned, and shall be immediately removed by the property owner in its entirety, including any towers, equipment and fencing. Lack of operation or full functionality may be evidenced by inspection, metering, documentation from the interconnected electrical utility or other evidentiary information.
(D) Bulk regulations.
(1) Setbacks.
(a) Free-standing SWECS. The minimum setback for every free-standing SWECS shall be 150% of the total height of the SWECS, as measured from every property line and the closest point of the SWECS, including blades the outer-most arc of the blades.
(b) Building-mounted SWECS. Every building-mounted SWECS shall comply with all of the minimum setback requirements of the principal building to which the SWECS, as measured to the closest point of the SWECS including the outer-most arc of the blades.
(2) Maximum height.
(a) The height of any building mounted SWECS shall not exceed a height of ten feet above the point of attachment to the principal building, as measured to the outer-most arc of the blades or other highest point on the SWECS.
(b) The height of a free-standing SWECS shall be the distance between the average ground elevation within the outer-most points of the SWECS’ swing according to wind direction, and the highest point of any part of the SWECS, including the turbine blades, and shall not exceed the maximum height allowed according to lot size and any other applicable regulations.
1. One acre or less. SWECS are prohibited by division (C) on lots whose area is one acre or less.
2. More than one acres but smaller than three acres. The maximum height shall be 65 feet.
3. A minimum of three but smaller than seven acres. The maximum height shall be 80 feet.
4. Seven acres or more in area. The maximum height shall be 100 feet.