(A) Definitions.
ABANDONMENT. Any solar energy system or facility that is no longer producing power, except for a temporary interruption of power for maintenance or repowering, which said period of temporary interruption shall not exceed 90 days, except by express permission of the City Council.
AGRIVOLTAICS. A solar energy system co-located on the same parcel of land as agricultural production, including crop production, grazing, apiaries, or other agricultural products or services.
BUILDING-INTEGRATED SOLAR ENERGY SYSTEMS. A solar energy system that is an integral part of a principal or accessory building, rather than a separate mechanical device, replacing or substituting for an architectural or structural component of the building. Building-integrated systems include but are not limited to photovoltaic or hot water solar energy systems that are contained within roofing materials, windows, skylights, and awnings.
COMMERCIAL SOLAR. Solar panels intended to power a single commercial business, which may be roof-mounted or ground-mounted on the same parcel as the business, or on an adjacent parcel owned by the same business.
COMMUNITY-SCALE SOLAR (HYBRID). A large solar array, typically smaller than a commercial array, which is built to meet the power needs of interested customers in a particular area
based upon a contract solely with the interested customer in that area. Utility-scale and community solar projects may be of any size, except as limited herein, and provided they meet the regulations contained in Chapter 159, including especially this section, and all other requirements of this code.
COMMUNITY SOLAR GARDEN. A solar energy system that provides retail electric power (or a financial proxy for retail power) to multiple community members or businesses residing or located off-site from the location of the solar energy system. Also referred to as shared solar.
DECOMMISSION. To remove or retire a solar energy system or facility from active service.
GROUND-MOUNTED SOLAR ENERGY SYSTEM. A solar energy system that is not attached to or mounted on any roof or exterior wall of any principle or accessory building.
HEIGHT. The height of a solar energy system, with all components, measured vertically from the adjacent grade to its highest point at maximum tilt.
LARGE-SCALE SOLAR ENERGY SYSTEM/SOLAR FARM. A commercial solar energy system that converts sunlight into electricity for the primary purpose of wholesale sales of generated electricity, and which has commercial use beyond providing power to the individual owner or business located on the parcel. A LARGE-SCALE SOLAR ENERGY SYSTEM will have a project size greater than the acreage necessary to service the building on the parcel and, for the life of the system, is the principal land use for the parcel(s) on which it is located.
OFF-GRID SOLAR ENERGY SYSTEM. A photovoltaic solar energy system in which the circuits energized by the solar energy system are not electrically connected in any way to electric circuits that are served by an electric utility company.
PHOTOVOLTAIC (PV) SYSTEM. A solar energy system that converts solar energy directly into electricity.
PRIVATE SOLAR ENERGY SYSTEM. A solar energy system used exclusively for private purposes and not used for commercial resale of energy, except for the sale of surplus electrical energy back to the electrical grid.
RENEWABLE ENERGY EASEMENT/ SOLAR ENERGY EASEMENT. An easement that limits the height or location, or both, of permissible development on the burdened land in terms of a structure or vegetation, or both, for the purpose of providing access for the benefitted land to wind or sunlight passing over the burdened land.
RESIDENTIAL SOLAR. Solar panels which provide power solely to a single residential building which may be roof-mounted or ground-mounted on the same parcel.
ROOF-MOUNT. A solar energy system mounted on a rack that is fastened to or ballasted on a structure roof. ROOF-MOUNT systems are accessory to the principal use.
SOLAR ACCESS. Unobstructed access to direct sunlight on a lot or building through the entire year, including access across adjacent parcel air rights, for the purpose of capturing direct sunlight to operate a solar energy system.
SOLAR CARPORT. A solar energy system of any size that is installed on a carport structure that is accessory to a parking area, and which may include electric vehicle supply equipment or energy storage facilities.
SOLAR COLLECTOR. A device, structure or a part of a device or structure for which the primary purpose is to transform solar radiant energy into thermal, mechanical, chemical, or electrical energy. The collector does not include frames, supports, or mounting hardware.
SOLAR ENERGY. Radiant energy received from the sun that can be collected in the form of heat or light by a solar collector.
SOLAR ENERGY SYSTEM. A device, array of devices, or structural design feature, the purpose of which is to provide for generation or storage of electricity from sunlight, or the collection, storage and distribution of solar energy for space heating or cooling, daylight for interior lighting, or water heating.
SOLAR MOUNTING DEVICES. Racking, frames, or other devices that allow the mounting of a solar collector onto a roof surface or the ground.
UTILITY SCALE SOLAR.
(a) A large-scale solar array which is designed to provide large-scale power output which is designed to service multiple parcels outside the parcel on which is situated, and which power is sold to multiple residential and commercial users in its service area. Examples include, but are not limited to:
1. A utility, municipality (if the electric utility is owned by a city), or an electric cooperative (in more rural areas) to serve both residential and commercial customers in their service area;
2. A corporation to power its needs in a particular region;
3. One or more large universities or other institutions in the same area that pool together to buy electricity.
(b) Utility-scale and community solar projects may be of any size, except as limited herein, and provided they meet the regulations contained in Chapter 159, including especially this section, and all other requirements of this code.
(B) Permitted accessory use. Solar energy systems are a permitted accessory use in all zoning districts where structures of any sort are allowed, subject to certain requirements as set forth below. Solar carports and associated electric vehicle charging equipment are a permitted accessory use on surface parking lots in all districts. Ground-mount solar in residential districts will be treated as an accessory structure and follow guidelines in division (B)(7) below. Solar energy systems that do not meet the following design standards will require a conditional use permit.
(1) Height. Solar energy systems must meet the following height requirements:
(a) Building- or roof-mounted solar energy systems shall not exceed the maximum allowed height in any zoning district. For purposes for height measurement, solar energy systems other than building-integrated systems shall be given an equivalent exception to height standards as building-mounted mechanical devices or equipment.
(b) Ground- or pole-mounted solar energy systems shall not exceed 15 feet in height when oriented at maximum tilt. In all residential districts, ground or pole mount must follow accessory building height restrictions.
(c) Solar carports in non-residential districts shall not exceed 20 feet in height from parking grade.
(2) Setback. Solar energy systems must meet the accessory structure setback for the zoning district and principal land use associated with the lot on which the system is located, except as allowed below.
(a) Roof- or building-mounted solar energy systems. The collector surface and mounting devices for roof-mounted solar energy systems shall not extend beyond the exterior perimeter of the building on which the system is mounted or built, unless the collector and mounting system has been explicitly engineered to safely extend beyond the edge, and setback standards are not violated. Exterior piping for solar hot water systems shall be allowed to extend beyond the perimeter of the building on a side-yard exposure. Solar collectors mounted on the sides of buildings and serving as awnings are considered to be building-integrated systems and are regulated as awnings. All roof mounting must follow IBC/IRC/NEC regulations.
(b) Ground-mounted solar energy systems. Ground-mounted solar energy systems may not extend into the side-yard or rear setback when oriented at minimum design tilt.
(3) Visibility. Solar energy systems in residential districts shall be designed to minimize visual impacts. Ground-mount must be in rear or side yard. Visibility standards do not apply to systems in non-residential districts, except for historic building or district review as described in division (B)(5) below.
(a) Building integrated photovoltaic systems. Building integrated photovoltaic solar energy systems shall be allowed regardless of whether the system is visible from the public right-of-way, provided the building component in which the system is integrated meets all required setback, land use or performance standards for the district in which the building is located.
(b) Aesthetic restrictions. Roof- or ground-mounted solar energy systems shall not be restricted for aesthetic reasons if the system is not visible from the closest edge of any public right-of-way other than an alley, or if the system meets the following standards.
1. Roof-mounted systems on pitched roofs that are visible from the nearest edge of the front right-of-way shall have the same finished pitch as the roof and be no more than ten inches above the roof.
2. Roof-mount systems on flat roofs that are visible from the nearest edge of the front right-of-way shall not be more than five feet above the finished roof and are exempt from any rooftop equipment or mechanical system screening.
(c) Reflectors. Solar energy systems using a reflector to enhance solar production are prohibited.
(4) Lot Coverage. Ground-mounted systems total collector area shall not exceed the allowable accessory building allowable size in any residential district, not to exceed 30% of rear yard. In commercial or manufacturing districts ground-mount systems shall not exceed half the building footprint of the principal structure.
(a) Ground-mounted solar farm systems shall be exempt from lot coverage or impervious surface standards if the soil under the collector is maintained in vegetation and not compacted.
(b) Solar carports in non-residential districts are exempt from lot coverage limitations.
(5) Historic buildings. Solar energy systems on buildings within designated historic districts or on locally designated historic buildings (exclusive of state or federal historic designation) must receive approval of the Community Heritage Preservation Commission or Clinton Historical Society, consistent with the standards for solar energy systems on historically designated buildings published by the U.S. Department of Interior.
(6) Plan approval required. All solar energy systems requiring a building permit or other permit from the city shall provide a site plan for zoning review.
(a) Plan applications. Plan applications for solar energy systems shall be accompanied by to-scale horizontal and vertical (elevation) drawings. The drawings must show the location of the system on the building or on the property for a ground-mounted system, including the property lines.
(b) Plan approvals. Applications that meet the design requirements of this section shall be granted administrative approval by the Zoning Official and shall not require Planning Commission review. Plan approval does not indicate compliance with Building Code or Electric Code.
(7) Approved solar components. Electric solar energy system components must have a UL or equivalent listing and solar hot water systems must have a SRCC rating.
(8) Compliance with Building Code. All solar energy systems shall meet approval of local Building Code Officials, consistent with IRC/IBC/NEC solar energy provisions, and solar thermal systems shall comply with all ICC codes as adopted by the city.
(9) Utility notification. All grid-intertie solar energy systems shall comply with the interconnection requirements of the electric utility. Off-grid systems are exempt from this requirement.
(C) Principal uses. The city encourages the development of residential, commercial, agricultural, and utility scale solar energy systems where such systems present few land use conflicts with current and future development patterns. Ground-mounted solar energy systems that are the principal use on the development lot or lots are conditional uses in selected districts.
(1) Use general standards; residential, commercial, and agricultural (private/owner). Principal use solar, where the solar is generated by the owner of the property for the use of the property owner.
(a) Site design.
1. Setbacks; residential, commercial and agricultural principle (owner) use solar. Ground-mount solar arrays are to be treated similar to an accessory structure, with all height, area, and setback requirements listed in
§
159.046(G).
2. Screening.
a. If required, a screening plan shall be submitted that identifies the type and extent of screening for ground-mount arrays.
b. Screening shall be consistent with the city's screening ordinance or standards typically applied for other land use requiring screening.
c. The city may require screening where it determines there is a clear community interest in maintaining a viewshed.
(2) Principal use general standards; community- and large-scale solar farm.
(a) Site design.
1. Setbacks. Community- and large-scale solar arrays must meet the following setbacks:
a. Property line setback for buildings or structures in the district in which the system is located, except as other determined in division (C)(2)(a)1.e. below.
b. Roadway setback of 15 feet from the ROW centerline of state highways and CSAHs, 100 feet for other roads, except as determined in division (C)(2)(a)1.e. below.
c. Housing unit setback of 150 feet from any existing dwelling unit, except as other determined in division (C)(2)(a)1.e. below.
d. Setback distance should be measured from the edge of the solar energy system array, excluding security fencing, screening, or berm.
e. All setbacks can be reduced by 50% if the array is fully screened from the setback point of measurement.
2. Screening. Community- and large-scale solar shall be screened from existing residential dwellings.
a. A screening plan shall be submitted that identifies the type and extent of screening.
b. Screening shall be consistent with the city's screening ordinance or standards typically applied for other land uses requiring screening.
c. Screening shall not be required along property lines within the same zoning district, except where the adjoining lot has an existing residential use.
d. The city may require screening where it determines there is a clear community interest in maintaining a viewshed.
3. Ground cover and buffer areas. The following provisions shall apply to the clearing of existing vegetation and establishment vegetated ground cover. Additional site-specific conditions may apply as required by the city.
a. Large scale removal of mature trees on the site is discouraged. The city may set additional restrictions on tree clearing or require mitigation for cleared trees.
b. The applicant shall submit a vegetative management plan prepared by a qualified professional or reviewed and approved by a natural resource agency or authority, such as the Natural Resources Conservation Service of the United States Department of Agriculture, Iowa State University Extension and Outreach, the Iowa Department of Natural Resources, and the Iowa Department of Agriculture and Land Stewardship. The plan shall identify:
i. The natural resource professionals consulted or responsible for the plan.
ii. The conservation, habitat, eco-system, or agricultural goals, which may include: providing habitat for pollinators such as bees and monarch butterflies, providing habitat for wildlife such as upland nesting birds and other wildlife, establishing vegetation for livestock grazing, reducing on-site soil erosion, and improving or protecting surface or ground water quality.
iii. The intended mix of vegetation upon establishment.
iv. The management methods and schedules for how the vegetation will be managed on an annual basis, with particular attention given to the establishment period of approximately three years.
c. Soils shall be planted and maintained in perennial vegetation for the full operational life of the project, to prevent erosion, manage run off and build soil.
d. Vegetative cover should include a mix of perennial grasses and wildflowers that will preferably result in a short stature prairie with a diversity of forbs or flowering plants that bloom throughout the growing season. Blooming shrubs may be used in buffer areas as appropriate for visual screening. Perennial vegetation (grasses and forbs) are preferably native to Iowa, but where appropriate to the vegetative management plan goals, may also include other naturalized and non-invasive species which provided habitat for pollinators and wildlife and/or other ecosystem services (i.e. clovers).
e. Plant material must not have been treated with systemic insecticides, particularly neonicotinoids.
4. Foundations. A qualified engineer shall certify that the foundation and design of the solar panel racking and support is within accepted professional standards, given local soil and climate conditions.
5. Power and communication lines. Power and communication lines running between banks of solar panels and to nearby electric substations or interconnections with buildings shall be buried underground. Exemptions may be granted by the city in instances where shallow bedrock, water courses, or other elements of the natural landscape interfere with ability to bury lines, or distance makes undergrounding infeasible, at the discretion of the Zoning Administrator.
6. Fencing. Perimeter fencing for the site shall not include barbed wire or woven wire designs, and shall preferably use wildlife-friendly fencing standards that include clearance at the bottom. Alternative fencing can be used if the site is incorporating agrivoltaics.
(b) Stormwater and NPDES. Solar farms are subject to the city's stormwater management and erosion and sediment control provisions and NPDES permit requirements. Solar collectors shall not be considered impervious surfaces if the project complies with ground cover standards, as described in division (C)(2)(a)3. of this section.
(c) Other standards and codes. All solar farms shall be in compliance with all applicable local, state and federal regulatory codes, including the State of Iowa Uniform Building Code, as amended, and the ICC Codes, as amended, and the National Electric Code, as amended.
(d) Site plan required. The applicant shall submit a detailed site plan for both existing and proposed conditions, showing locations of solar arrays, other structures, property lines, rights-of-way, service roads, floodplains, wetlands and other protected natural resources, topography, electric equipment, and all other characteristics requested by the city. The site plan should show all zoning districts and overlay districts.
(e) Aviation protection. For solar farms located within 500 feet of an airport or within approach zones of an airport, the applicant must complete and provide the results of a glare analysis through qualitative analysis of the potential impact, field test demonstration or geometric analysis of ocular impact in consultation with the Federal Aviation Administration (FAA) Office of Airports, consistent with the Interim Policy, FAA Review of Solar Energy Projects on Federally Obligated Airports, or most recent version adopted by the FAA.
(f) Agricultural protection. Solar farms must comply with site assessment or soil identification standards that are intended to identify agricultural soils. The city may require mitigation for use of prime soils for solar array placement, including the following:
1. Demonstrating co-location of agricultural uses (agrivoltaics) on the project site.
2. Using an interim use or time-limited CUP that allows the site to be returned to agriculture at the end of life of the solar installation.
3. Placing agricultural conservation easements on an equivalent number of prime soil acres adjacent to or surrounding the project site.
4. Locating the project in a wellhead protection area for the purpose of removing agricultural uses from high risk recharge areas.
(g) Decommissioning. A decommissioning plan shall be required to ensure that facilities are properly removed after their useful life. Said decommissioning plan shall be implemented immediately upon the end of operations of any large-scale or community scale solar field. This provision shall not apply if the solar field temporarily ceases to operate for maintenance or repowering purposes, which temporary cessation shall not exceed 90 days, unless a waiver of the same is granted by the express permission of the City Council.
1. Decommissioning of the system must occur in the event the project is not in use for 12 consecutive months.
2. The plan shall include provisions for removal of all structures and foundations, restoration of soil and vegetation and assurances that financial resources will be available to fully decommission the site.
3. Disposal of structures and/or foundations shall meet the provisions of the city’s solid waste ordinance.
4. The city may require the posting of a bond, letter of credit or the establishment of an escrow account to ensure proper decommissioning.
(3) Community-scale and large-scale solar farms.
(a) Community-scale solar. The city permits the development of community-scale solar, subject to the following standards and requirements:
1. Community-scale ground-mounted. Community solar energy systems are a permitted use in M Districts only, as further specified in this chapter.
2. Standards. All structures must comply with setback and height, standards for the M District in which the system is located.
3. A special use permit shall be required from the Zoning Board of Adjustment prior to installation of any community-scale solar array.
(b) Large-scale solar. Ground-mounted solar energy arrays that are the principal use on the lot, designed for providing energy to off-site uses or export to the wholesale market, are permitted only in the following areas under the following standards:
1. M-1 and M-2 Districts:
a. Solar fields may only be installed on sites that are 25 contiguous acres or less.
b. The property shall be maintained by cutting or destroying all grasses, weeds, vines and brush when the growth exceeds eight inches in height.
2. M-3 Districts south of Highway 30 and west of South 54th Street.
a. Solar arrays may be any size.
b. Solar arrays may only be installed on sites south of Highway 30 and west of South 54th Street.
c. The property shall be maintained by cutting or destroying all grasses, weeds, vines, and brush when the growth exceeds eight inches in height.
d. For prairie grass plots and pollinator pockets around solar arrays, the growth shall be mowed or otherwise reduced to eight inches in height a minimum of once per calendar year.
3. A special use permit shall be required from the Zoning Board of Adjustment prior to installation for any large-scale solar array. Further, City Council permission, including any required additional limits or conditions the Council deems appropriate, shall be required.
(c) Applicant must provide for any community-scale or large-scale solar farms contemplated, an opinion from a certified Iowa professional engineer, outlining the removal and disposal procedure for all solar panels once said panels are decommissioned due to failure, damage or other defect, including a fair market value estimate of decommissioning and disposal costs of the same. Said cost of decommissioning and disposal must be updated with a supplemental report to Building and Neighborhood Services every two years following initial completion of the solar array, beginning on the two-year anniversary of completion. Further, applicant must provide proof of a bond in an amount sufficient to pay for all decommissioning and disposal of the entire solar array on the permitted property. In lieu of a bond, applicant may provide a cash deposit in the amount of the engineer's decommissioning estimate, which shall be kept in an interest-bearing account by the city. Said bond or cash deposit shall be increased commensurate with any recommended increases by the applicant's engineer during the life of the project. In the event of a cash deposit which is not depleted by the decommissioning and disposal costs, the remainder, plus any accrued interest on the remainder, shall be refunded to the applicant, or applicant's successor.
(d) In the event that applicant sells or transfers any ownership interest in the array during the life of the array, said transfer documents shall contain reference to this section and the decommissioning requirement. All successor owners shall be subject to this provision.
(e) No special use permit shall be granted for any community-scale or large-scale solar farm unless the project limit is at least 300 feet from any residential structure.
(f) All special use permits and conditional use permits for community-scale or large-scale solar farms shall require written notice, consistent with city and state zoning notice requirements, to all property owners whose lot lines are within 1,000 feet of the lot lines of the proposed parcel where the solar farm is contemplated to be built.
(g) All community-scale or large-scale solar farms shall be built no closer than 50 feet from any public right-of-way.
(h) All community-scale and large-scale solar farms shall be installed in such a way to eliminate any glare or reflection causing a nuisance to any other property, and screening in the form of trees, berms, fences and the like may be imposed as the Zoning Board of Adjustment, or the City Council may deem appropriate.
(i) No community-scale or large-scale solar farm shall be granted any special use permit if the proposed location is within one air mile of any existing previously approved community-scale or large-scale solar farm within the city limits.
(4) All solar projects. All solar shall be installed in such as way to eliminate any glare or reflection causing a nuisance to any other property.
(Ord. 2734, passed 11-28-2023; Ord. 2736, passed 3-26-2024; Ord. 2747, passed 6-11-2024)