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HomeMy WebLinkAbout2017-08-28 PACKET 06.2.STAFF REPORT CASE: ICUP2017-028 ITEM: 6.2 PUBLIC MEETING DATE: 8/28/17 TENTATIVE COUNCIL REVIEW DATE: 9/20/17 APPLICATION APPLICANT: Novel Werner Solar One LLC REQUEST: An interim conditional use permit to allow a 750 KW AC roof -mounted community solar garden at Werner Electric. SITE DATA LOCATION: ZONING: GUIDED LAND USE: 7450 95th Street South 1-2, General Industry Industrial LAND USE OF ADJACENT PROPERTIES: CURRENT GUIDED NORTH: Parks & Open Space Parks & Open Space EAST: Industrial Industrial SOUTH: Low Density Residential Low Density Res. WEST: Low Density Residential Low Density Res. SIZE: N/A DENSITY: N/A RECOMMENDATION Approval, subject to the conditions stipulated in this staff report. Cottage J rove COTTAGE GROVE PLANNING DIVISION G 4�Ile pride and ,,.,p-ritY Meet Planning Staff Contact: John McCool, Senior Planner; 651-458-2874; 4mccooI(d,)cottage-grove. org Application Accepted: 7/31/17 60 -Day Review Deadline: 9/29/17 City of Cottage Grove Planning Division • 12800 Ravine Parkway South • Cottage Grove, MN 55016 Planning Staff Report Novel Werner Solar One LLC — Interim Conditional Use Permit (Community Solar Garden) Planning Case No. ICUP2017-028 August 28, 2017 Proposal Novel Werner Solar One LLC has applied for an interim conditional use permit for the proposed installation of roof -mounted solar panels on the roof of the Werner Electric building at 7450 95th Street South. Electricity generated from the roof -mounted panels will feed inverters that ultimately connect to Xcel's electric distribution system. The solar panels will be installed on the roof of Werner Electric's warehouse building. The cluster of rooftop solar arrays will have the capacity of generating 750 kilowatts of electric energy. The primary metering switchgear, grounding equip- ment, and transformers will be placed on three 18.5 -foot by 16 -foot concrete slabs that will be constructed on the southwest corner of Werner's warehouse building. The solar collector arrays will be stationary (non -rotating) on the roof. All 12 solar arrays will be constructed in one phase. The illustration below shows the location of Werner Electric's property at 7450 95th Street. Project Location Map Review Process Application Received: July 31, 2017 Acceptance of Completed Application: July 31, 2017 Tentative City Council Date: September 20, 2017 60 -Day Review Deadline: September 29, 2017 Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 2 of 10 Ordinance Regulations The City's Solar Collector System ordinance was adopted by the City Council on October 7, 2015 (Ord. No. 948). This ordinance defines a "community solar garden" as a solar -electric (photovoltaic) array that provides retail electric power to multiple community members or businesses residing or located off-site from the location of the solar energy system, under the provisions of Minnesota Statutes 216B.1641 or a successor statute." Werner Electric is proposing to develop a community solar garden as part of the Xcel Community Solar Garden Program, as regulated by the Minnesota Statutes 216B.1641. This program allows individuals, businesses, schools, and civic entities (known as "subscribers") to purchase or "sub- scribe" to a portion or a "share" of the output from a given solar garden. This allows subscribers to purchase renewable energy at a savings compared to their current utility bill without making costly upfront investments in a solar collection system. On July 19, 2017, the City Council adopted Ordinance No. 985 that amended the solar collection system ordinance to require an interim conditional use permit versus a conditional use permit and to allow community solar gardens within the metropolitan urban service area (MUSA) only if they are roof -mounted solar units on non-residential structures. Based on these new solar energy sys- tem regulations, Werner Electric is proposing to install a 750 kilowatt community solar garden on their roof. Werner Electric's proposed community solar garden project is in conformance with the new regulations as long as they comply with conditions. Community Solar Garden Project Novel Werner Solar One LLC is proposing a community solar garden on the roof of Werner Elec- tric's warehouse building that will have the capacity to generate up to 750 kilowatts of electricity. Construction of this community solar garden is planned to start in the fall of 2017. During the start of construction, an average of two semi -trailers delivering and storing solar equipment and mate- rials will access the property per day. Construction of the community solar garden is expected to take four weeks. The applicant is proposing to mount solar collection panels on a racking system that will utilize a 10 degree tilt. Each solar module is approximately 39 inches wide and 78 inches long. The depth is approximately 1.6 inches and has a weight of approximately 47 pounds per module. There are approximately 2,862 photovoltaic (PV) modules that will be fixed to a rooftop racking system. The front edge (south side) of the module's tilt will be approximately six inches above the roof and the back edge (north side) of the module's tilt will be approximately 13 inches. The illustration below shows a side view of the racking system. SIDE VIEW F 1Y 18' 0 6 = 0 19' r6 Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 3 of 10 4.20 + {106.65} i 11.53 (292.85) 15.63 (397) 15.75 (400) 15.63 (397) 15.73 (399.50) 39.4 (1001) IWON- M1 78.46 (1993) DIMENSIONS WEIGHT HT Length 78.46 in (1993 mm) Width 39.40 in (10{ 1 mm) Height 1°30 in (33 mm) 1 weight 1.30 {33} Module Dimensions and Weight A4"iOV!IL11I &I 47.6 Ib (1.° kg) a 9nshar sikv : tiau d I:v1ba Ir. k,' ::xl tl:l l:Ixl nXn+ IXl:llr°n I:uy I:I Ynl:l l:'.x Ilrl. +Ilk IN[ K:y :,I :HI. k..l:l kn l: Ix–;x;x-il-xlY:-�I.:I:Irr. x.11xl tiI:li-IIx-1:r:l.- � I--Rrkwl. .1gh -.11ltlarcY: °I - ua1_Ix XIIk:N -ty lap',n 7T,111'fJ° IYoe;p- I aalln, low•Ilgh! Peelormanam: �d V9lI::X❑ L11:114 :Ind -Id- 1:11 —IOC:X `t Sl .rl'q 1:11—'C• A.C::Xll—I xtl:rm:l-I:xh :r�47,l tnai:l-Ilx•.n11. 1.I SaYeaa Weaihar Roill Once. 1= .:sI —11: %TN111:1ti1 x.,It—' :N -M is 1:�:1M1tl ln:rx F.:1:1 :=171.°IPJIC:v'[. Ilurow" agd -M calren°e awronmmanral con91111ar-k 662 °1fl• 1:u–�-:urtl :mm:r F. u�11:1r.cx cx•1rX:11 rr n.r •tali.;°. LINEAR PERFORMANCE WARRAWY 1Q Yrs hod.cl W—..ly- 2se— unto, r,a MLm.r{ Module Appearance Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 4 of 10 all -PM P� Proposed Roof Mounting System VMS Proposed Roof Mounting System Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 5 of 10 Proposed Roof -Top Community Solar Garden City staff requested for more details describing these interconnection facilities. The applicant stated that these details have not yet been prepared and that they continue to work on the design with Xcel Energy. The applicant's written narrative states that these facilities are typically owned and maintained by the utility company and the solar garden operator will require their own identical set of interconnection facilities operating in parallel with the utility's facilities. At this time, the ap- plicant believes the conveyance of electric energy generated by the community solar garden will connect to an existing underground Xcel electric line in 95th Street. The applicant understands that all electrical lines must be underground, but said that Xcel Energy has final jurisdiction over the interconnection scheme and that the precise number and locations of electrical distribution lines cannot be determined at this time. City ordinance requires all power lines be placed underground within the interior of the community solar garden property. Details of this interconnection between the community solar garden and Xcel's electric grid must be submit- ted to the City before a building permit is issued for this project. Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 6 of 10 Glint and Glare Study A Glint and Glare Study (August 18, 2017) was prepared by the applicant's consultant for Novel Werner Solar One, LLC project. This study was prepared to answer questions if neighboring prop- erty owners will experience any potential impacts of glint or glare from photovoltaic (PV) modules. Glint is defined as a momentary flash of bright light and glare is a reflection of bright light for a longer duration. The study describes the solar PV modules proposed on the Werner Electric's roof constructed of high transmission, low iron glass and are covered with anti -reflective coatings. Since the function of a solar PV module is to absorb solar radiation and convert it to electricity, these PV modules will reflect as little as two percent of incoming sunlight, which is significantly less light than flat water or standard window glass. Figure 5 from the study shows the reflectivity of solar modules relative to other natural and manmade surfaces. Figure 5 is shown below. 100 75 c ti} c LU 25 D is 3D 45 64 75 GLS IncidentAngle of SurlllgM (Degrees) -Steel Glass Smooth Water Solar Glass WAR Figure S: Analysis of Typical Material Reflec#ivitywittl Sunlight Angle JSource: Capital Solar Farrn Visual Impact Assessment, 2010) The study also showed that for glare to appear, the observer must be able to see the tops of the PV modules. For this to occur, the observer would need to be at a height sufficient to slightly look down at the tops of the solar modules that are proposed to be mounted on Werner Electric's warehouse roof. There are residential homes south and west of the Werner Electric site. The closest residential dwelling to Werner Electric's warehouse is approximately 443 feet to the south- west. Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 7 of 10 Photographs from Residences Southwest of Werner Electric The photographs above were taken from Harkness Avenue. Werner Electric's roof height appears to be slightly higher than the view standing on Harkness Avenue. It might be possible for residents to look down on the top of Werner Electric's warehouse structure from their second floor. The study identified 10 homes southwest of Werner Electric's warehouse as having a low potential for temporary glare from March 15 through May 10 and August 3 through September 25 between 6:00 a.m. and 7:30 a.m. This low potential for temporary after -image is the lowest class of viewing hazard predicted by the model results referenced in the study. The Glint and Glare Study is attached. Comprehensive Plan Conformance The Future Land Use map in the City's approved Future Vision 2030 Comprehensive Plan desig- nates this property for industrial land uses. The General Industry (1-2) zoning classification and the current land use on this property are consistent with the Comprehensive Plan. The 20.1 -acre site is located inside the MUSA. Planning Considerations Property Characteristics Werner Electric's site is approximately 20.1 acres in land area. Their office and warehouse facility is a one-story building with approximately 178,522 square feet for their building footprint. There are 300 parking spaces for passenger vehicles along the west side of the office/warehouse struc- ture, and truck loading docks exist along the east side of the warehouse building. Two private access driveways connect to 95th Street. The site plan for Werner Electric is shown on the next page. Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 8 of 10 ' \ i �1 eaaarw exnas � ^PROPOSED r t L � \1 -- vnoiaon ■ �� nom:+er..w _ — f L L L L ti r >\ L l \ _M — -- -- ___ I — 41 95TH S T, So. — Werner Electric Site Plan 8 The site's topography is relatively flat, but its base ground elevation is approximately 24 feet lower than the residential properties west of the Werner Electric site. Werner Electric's warehouse has a height of approximately 36 feet, and the one-story office is 18 feet, 4 inches in height. Decommissioning Plan The applicant's decommissioning plan states that within 180 days of the end of the project's useful life, all of the solar arrays, cables, electrical components, and other ancillary facilities owned by the community solar garden will be removed. These solar components will be disconnected, re- moved from the racks, packaged, and transported to a designated location for resale, recycling, or disposal. The panel racking system will be unbolted, disassembled, and transported off-site for salvage or reuse. All electrical equipment, buildings, and foundations will also be removed from the site. A cost estimate for decommissioning the entire community solar garden facilities has not yet been submitted to the City. This cost estimate is required in order to determine the minimum financial guarantee amount that the applicant is required to provide to the City. The applicant is required Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 9 of 10 to provide the City with a cash escrow, irrevocable letter of credit, or a signed assessment waiver agreement in an amount equal to 125 percent of the accepted decommissioning estimate. The financial guarantee must be submitted to the City before a building permit will be issued by the City. Public Hearing Notices The public hearing notice was published in the South Washington Bulletin and mailed to 62 prop- erty owners within 500 feet of the 20.1 -acre site on August 16, 2017. Recommendations That the Planning Commission recommend that the City Council approve interim conditional use permit application filed by Novel Werner Solar One LLC for the proposed installation of a 750- kilowattt roof -mounted community solar garden system on the roof of the Werner Electric building at 7450 95th Street South. The Planning Commission can consider staff's proposed conditions approving this interim condi- tional use permit application based on testimony and discussion at the public hearing. Conditions of approval for your consideration are listed below. The interim conditional use permit shall be granted for a 25 -year period that will expire on September 20, 2042. 2. The applicant must provide to the City a cost estimate for decommissioning the entire com- munity solar garden facilities. Upon the City's acceptance of the decommissioning cost estimate, the applicant shall provide the City with a cash escrow, irrevocable letter of credit, or assessment waiver agreement in an amount equal to 125 percent of the accepted decommissioning estimate. The financial guarantee must be remitted to the City before a building permit will be issued. 3. All on-site and off-site electric power lines necessary to interconnect the electric power created from the community solar garden to the utility company grid system must be underground. 4. The project must comply with the City's Solar Energy System Ordinance regulations. 5. Any existing landscaping that must be removed because of the three 18.5 -foot by 16 -foot concrete slabs on the west side of the warehouse building must be replaced or relocated on the Werner Electric property. 6. The solar PV modules are covered with anti -reflective coatings. 7. Exterior storage of solar panels and ancillary materials/equipment are temporarily allowed on Werner Electric's site during construction and installation of the community solar gar- den. Once the community solar garden project is constructed, no exterior storage of the solar garden components is allowed outside Werner Electric's existing outdoor storage area or building. Planning Staff Report — Planning Case No. ICUP2017-028 Werner Electric Rooftop Solar Community Garden August 28, 2017 Page 10 of 10 8. Parking off-site is prohibited. 9. Hours of construction is allowed between the hours of 7:00 AM and 7:00 PM, Monday through Friday and between the hours 9:00 AM and 7:00 PM, Saturday. Prepared by: John McCool, AICP Senior Planner Attachments: Novel Werner Solar One LLC ICUP Narrative Novel Werner Solar One LLC's Responses to the ICUP Ordinance Criteria Werner Electric PV Site Layout Werner Electric SRC049589 — Sheets 1 and 2 of 3 Werner Electric SRC050653 — Sheets 1 and 2 of 3 Werner Electric SRC050652 — Sheets 1 and 2 of 3 Solar Glare Study (August 18, 2017) Novel Werner Solar One LLC Introduction Community Solar Gardens are supported by the State of Minnesota as a renewable energy supply. The Xcel Energy program was approved by the State of Minnesota as part of the renewable energy jobs bill in 2013. The purpose of constructing a community solar garden (solar array) will be to generate offsite solar energy that will be connected directly to the electric grid for the on-going benefit of subscribers to the solar garden. As many as 75% of homes and businesses are unable to install solar at their property making off-site solar energy production their only option. This proposed site will be constructed to produce 750KW AC of electric generation. The electrical energy will be distributed directly to the existing electrical grid for subscribers to the energy produced by the system. The impact to the area is low from a construction, operation, and end of life perspective. Construction and setup are not invasive. Solar energy production is a passive activity, and the system does not alter the underlying nature of the land which can be returned to any other appropriate use. The system will reduce the carbon footprint and greenhouse gas emissions. Subscribers to the community solar garden will save on their electric bills over the 25 year life of the agreement with Xcel Energy, money which can be saved and spent in support of the local economy. Community solar gardens offer numerous benefits to the community. Subscribers have an opportunity to keep electric dollars in the area to support the local economy. Land owners have a new option that brings value to their property without impacting the underlying nature of the land. Harvesting the sun entails far less risk than other commodities. Land owners and the community have an opportunity to be leaders in renewable energy that sets an example for others to follow, and leaves a positive lasting legacy. Distributed solar generation, energy produced at multiple locations across the grid helps prevent electric line loss and dependence on carbon -based fuel sources. Careful siting standards protect the integrity of the land, increases production which increases local revenues and savings, and ensures positive neighbor relations. Solar panels and systems have been used in the United States for over forty years and have gained in popularity as the cost of solar energy becomes competitive with traditional fossil fuels, and because of positive environmental benefits. Solar systems are more widely found on the east and west coasts of the United States due to higher electric costs than Minnesota and the Midwest. Solar systems have been found to be good neighboring land uses due to their passive nature, no negative impact on neighbor property values, and benefits to the environment and local economy. Description The parcel is owned by Wer Dis LLC, more commonly known as Werner Electric PIN 20.027.21.24.0034 Legal Description: 20.1 acres. Hamlet Park S Lot 1, Block 1, Subject to Easement Novel Werner Solar One LLC Parcel Description: General Industrial Zoning Classification Site Access: Access off 95`h St. S Equipment The project will consist of roof mounted panels which will feed inverters which ultimately connect to the electric grid at the point of interconnection, engineered to meet industry, state and federal standards. The primary metering switchgear, grounding equipment and transformers will be placed on three concrete slabs on grade sized 18.5'x16' on the southwest corner of the building. All non-Xcel Energy equipment, materials, supplies, concrete, etc. will be removed at the end of the useful life of the project. All equipment must meet Xcel Energy and national standards for safety and interconnection. Program requirements include adequate levels of insurance coverage and a signed interconnection agreement as required by the MN Public Utilities Commission for 25 years, with continual production monitoring. Site Appearance & Impact The property has the Werner Electric facility located on it and the panels will be installed on the roof of the building. The attached layouts provides the proposed layout which is subject to final structural engineering. The final layout will continue to meet all City of Cottage Grove requirements and performance standards. Construction Construction activities will begin in late summer or fall of 2017. All necessary equipment and supplies will be delivered within a 2-4 week period at the start of construction. During the start of construction there will only be an average of two semi -trailers per day. Construction is expected to take 4 weeks. Temporary parking and staging will be off-road on the property. Disposal of waste materials will comply with all local, state and federal regulations and best practices. Potential to Effect the Environment and Public Health This project is focused on bringing additional green energy to people in Minnesota unable to access solar on their property, and reduce Xcel Energy's and the state's carbon emissions. The proposed solar array is passive and is designed to capture the sun's rays, not reflect them. Solar panels have an equivalent glare factor as a body of water. Research on potential environmental and public health issues will be through the State of Minnesota and the Federal government databases to ensure Novel Werner Solar One LLC compliance. The many -decade history of solar panel use has not identified public health or environmental issues. Decommissioning and Insurance Within one hundred eighty (180) days of the end of the project useful life, decommissioning will include the removal of all of the solar arrays, cables, electrical components and other ancillary facilities owned by the solar garden. The Xcel Energy tariffs governing this program and all interconnection as approved by the MN Public Utilities Commission includes interconnection and insurance requirements. Sections 9 & 10 of Xcel Energy's tariff for the Solar*Rewards Community, and Interconnection respectively spell out the requirements. Insurance coverage includes a $2 million per occurrence policy, and interconnection to the Xcel Energy grid cannot occur until all safety and security items have been engineered, reviewed and approved. State and National electrical codes must be met, inspected and approved prior to interconnection. A signed interconnection agreement with Xcel Energy will be provided prior to construction activities. Conclusion We are excited to complete this project in a strong partnership with Werner Electric and the City of Cottage Grove. We are committed to following best practices and all State, Federal and local rules and regulations to develop a community solar garden providing the many benefits to the local community. Cottage e Grove a Community Development Department Planning Division ,�� nese 12800 Ravine Parkway South Telephone: 651-458-2827 "'■ it, Pride a(%6 71." v Cottage Grove, MN 55016 Fax: 651-458-2897 www. cottage-grove. org E -Mail: planning as cottage-grove.org CONDITIONAL USE PERMIT/INTERIM CONDITIONAL USE PERMIT RESPONSE TO ORDINANCE CRITERIA In order to aid in the review process, please give a DETAILED response to the following ordinance criteria on this form or on separate exhibits. Your ability to meet the criteria is what the Planning Commission/City Council is required, in part, to base their review, so be specific. A. Will the use be in conformity with the City's Comprehensive Plan and with the purpose, intent, and applicable standards of the Zoning Ordinance? EXPLAIN. The Use will be in conformity with the Comprehensive Plan and the new Solar Ordinance approved on 7/19/17 B. The use shall be located, designed, maintained and operated to be compatible with the existing or intended character of that zoning district in which it is located. How does the proposed use fit these criteria? The use will be a rooftop community solar garden on an existing building C. The use shall not depreciate values of surrounding property. Explain effects of the proposed use on surrounding property values. The roof mounted system will have no impacts on surrounding property as the impervious surface is not changing and the property is within the Industrial zoning classification D. The use shall not be hazardous, detrimental or disturbing to present and potential surrounding land uses due to noises, glare, smoke, dust, odor, fumes, water pollution vibration, general unsightliness or other nuisances. Explain effects of proposed use. The panels have an anti -glare coating and there is no noise, smoke, dust, odor, fumes, or other nuisances E. The use shall generate only minimal vehicular traffic on local streets as defined by the Transportation Element of the Comprehensive Plan. The use shall not create traffic congestion, unsafe access, or parking needs that will cause inconveniences to the adjoining properties. Explain the transportation needs for the proposed use. There will be little to no vehicular traffic associated with use after construction is completed. F. The use shall be served adequately by essential public services such as streets, police, fire protection and utilities. Explain how the proposed use will be served. The use will be served by existing essential public services as it is a roof mounted solar system that is being placed on an existing building. G. The use shall not create excessive additional requirements at public cost for public facilities and services and shall not be detrimental to the economic welfare of the City. Justify this statement. This use will not create additional public cost or be detrimental to the economic welfare of the City. It will actually bring an economic benefit to the City as keeping energy savings local and will provide more taxes to the City H. The use shall preserve and incorporate the site's important natural and scenic features into the development of adjacent vacant land. Will these criteria be met? Again, this is a roof top mounted solar system and will not be changing any natural or scenic features I. The use shall cause minimal adverse environmental effects. List any effects. The system will not create any adverse environmental effects and will actually reduce the carbon footprint by adding renewable energy. Applicant Name: Novel Werner Solar One LLC Case #: Response to CUPACUP Criteria Page 2 of 2 J. The use shall not adversely affect the potential development of adjacent vacant land. List any potential problems. The use will not adversely affect the potential development of adjacent vacant land as it will be placed on an existing building and is located within an industrial area. In addition to the general criteria for Conditional Use Permits, the following additional requirements apply to Interim Conditional Use Permits: K. The period(s) of time for which the Interim Conditional Use Permit is to be granted will terminate before any adverse effects are felt upon adjacent property. The Solar panels have a 25 year guarantee to run at 100%, after that they will be at approximately 80% efficiency for a 5 year period. A 25 year IUP is requested with the ability to extend for an additional 5 years L. There shall be adequate assurance that the property will be left in suitable condition after the use is terminated. What measures are you intending to take to return the property to a suitable condition? At the time of decommissioning, the panels and all associated materials will be removed from the site. M. The use conforms to the zoning regulations. X Yes No N. What is the time frame you intend on utilizing the Interim Conditional Use Permit? Construction is anticipated to begin in early fall of 2017. O. Permission of the use will not impose additional costs on the public. Are any additional public safety or public works personnel required? How do you intend to reimburse the City? There will be no additional public safety or public works personnel required for this project. P. The user agrees to any conditions that the governing body deems appropriate for permission of the use. Agreed. 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The array will consist of a series of approximately 2,862 monocrystalline silicon photovoltaic (PV) modules fixed to a rooftop racking system. It will be built on an area of approximately 92,636 square feet and have an installed capacity of 1 MW. Specifically, this study answers the following questions: 1. Will glint and glare from the PV modules be visible to residents near the project? 2. If the glint and glare is visible, how long will it occur and when will it occur? 3. If the glint and glare is visible, what is it comparable to? 1.1 General Discussion of Reflection With growing numbers of solar energy systems being proposed and installed throughout the United States, the potential impact of glint and glare from PV modules and other types of solar collection systems is receiving increased attention as a potential nuisance to neighboring residential properties or potential hazard or distraction for pilots and air-traffic control personnel at nearby airports. A common misconception about solar PV modules is that they inherently cause or create "too much" glare, posing a nuisance to neighbors and a safety risk for pilots. While in certain situations the glass surfaces of solar PV systems can produce glint (a momentary flash of bright light) and glare (a reflection of bright light for a longer duration), light absorption, rather than reflection, is central to the function of a solar PV panel - to absorb solar radiation and convert it to electricity. Solar PV modules are constructed of high transmission, low iron glass and are covered with anti -reflective (AR) coatings. Modern PV modules reflect as little as two percent of incoming sunlight, about the same as water and less than soil or even wood shingles (Sandia 2014). 1.1.1 Reflection Type from Solar Modules Smooth surfaces such as glass and still water exhibit 'specular reflection`. This is when light hits the surface at one angle and 'bounces off' in another direction, much like a mirror. Specular reflection can be contrasted with 'diffuse reflection', which occurs when light reflects off microscopically rough surfaces and scatters. Diffuse reflection is what happens when light hits virtually everything in our field of vision. Figure 3 illustrates the difference between the two types of reflections. Since solar modules are flat and have a relatively smooth surface, most of the light reflected is specular, which means that incident light from a specific direction is reradiated in a specific direction. 1 Z Grovk Hdght5 Cotlage Grov. Washington County Dakota County I % i Legend Werner Solar Project Project Boundary N Cottage Grove, Washington County, Minnesota rl 6mmmmm===I Miles Westwood i County Boundary A. Site Location Map FIGURE I I J r. r . �k r � - V Y yl WesWOO( j,- Minn 1� _ �f Legend Project Boundary F=—]. Solar Array N A Feet o 100 ►verner solar Project Cottage Grove, Washington County, Minnesota Project Site Map FIGURE 2 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 Specular Diffuse Figure 3: Specular and Diffuse Reflections When the sun is reflected on a smooth surface, it can result in glint or glare for those who are on the 'receiving' angle. In both cases the light reflected is diminished by having first hit the substrate that reflected it—unless that surface is a perfect mirror. When the sun is the original source of the light reflected off a reflective surface, the time and position at which glare or glint might occur depends on the original position of the sun in the sky in relation to the location of the viewer. 1.1.2 Relative Reflectance of Solar Modules Compared to Other Surfaces Solar modules are designed to absorb light, and accordingly reflect only a small amount of the sunlight that falls on them compared to most other everyday objects. Most notably, solar modules reflect significantly less light than flat water or standard window glass. In fact, glass, one of the uppermost and important components of a solar panel, reflects only a small portion of the light that falls on it—about 2-4 percent, depending on whether it has undergone an AR treatment. To increase solar panel efficiency and power output, most of the solar PV modules in use today are treated with an AR coating. Figure 4 is an example of how antireflective technology can increase light transmission in glass and reduce overall reflection. Standard low -iron glass reflects approximately 8 percent of light, whereas AR -glass modules reflect a total of approximately 2-3 percent of the light. Conventional Glass 1 % Absorption 4% Reflection 4% Reflection JW 91% Transmission AR -Glass 1 % Absorption Figure 4: Light Transmission of Glass 4 1.5% Reflection 1.5% Reflecti '%W 96% Transmission Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 A number of studies have been conducted which have measured the intensity of reflections from PV solar modules with respect to other naturally occurring and manmade surfaces. The results of the studies show that reflections of the sun from solar modules are possible; however, the reflections produced will be of intensity similar to or less than those produced from still water and significantly less than reflections from glass and steel. Figure 5 and 6 below show the reflectivity of solar modules relative to other natural and manmade surfaces. 100 0 0 15 30 45 60 75 Incident Angle of Sunlight (Degrees) Steel — Glass — Smooth Water — Solar Glass WAR 90 Figure 5: Analysis of Typical Material Reflectivity with Sunlight Angle (Source: Capital Solar Farm Visual Impact Assessment, 2010) Figure 6: Albedo Comparison for Various Surfaces (Source: Capital Solar Farm Visual Impact Assessment, 2010) 5 Q 1 0.75 C ca U N 0.50 O N Q 0.25 O CU oc`v cn ca U C7 toco �i � GL •c Figure 6: Albedo Comparison for Various Surfaces (Source: Capital Solar Farm Visual Impact Assessment, 2010) 5 Glint and Glare Study— Novel Werner Solar One Rooftop Solar Project August 18, 2017 One measure of the reflectivity is albedo, the ratio of solar radiation across the visible and invisible light spectrum reflected by a surface. Albedo varies between 0, a surface that reflects no light, and 1, a mirror-like surface that reflects all incoming light. Solar PV modules with a single AR coating have a reflectivity of between 0.03 and 0.18. By comparison, sand has an albedo between 0.15 and 0.45 and agricultural vegetation has an albedo between 0.18 and 0.25. In other words, the solar PV modules have a lower reflectivity than the area's prevailing ground cover, agricultural crops. 1.2 Important Considerations When reflection occurs, unless it is directed toward, and seen by, an abutting property (referred to later as a "receptor" or "observer"), glint will not pose a concern. This was determined after a solar glare analysis using actual module surface characteristics from the PV module manufacturer. Before considering the mathematics of sunlight reflectivity, it is important to understand several fundamental limitations concerning the extent to which glare might be visible to nearby residences. First, for glare to appear, the observer must be able to see the tops of the PV modules. For this to occur, at a minimum, the receptor would need to be at a height sufficient to slightly look down at the tops of the solar modules mounted on the building roof. Lastly, glare is avoided when vegetation or other impediments are located between the observer and the solar modules. A home, for example, may be in the general area of a site with solar PV modules. That house, however, is at no risk of exposure to solar glare if other building or trees stand between it and the solar modules. 1.3 Overview of Sun Movements and Relative Reflections The basic concept to understand in any discussion of glare elevation is that the angle of incidence is always equal to the angle of reflectance. The empirical inquiry is then whether the potential observer is within the altitude of reflection given the distance of the observer from the solar PV panel. At any angle of reflectance, as a potential observer is further and further away from the solar PV panel, the elevation of the reflected sunlight (i.e., any glare) is more likely to be above the observer and, thus, not seen. In contrast, at a high angle of reflectance, the elevation of reflected sunlight will likely be above the observer -even at short distances. Given the basic principle of light reflectivity, evaluating the angle of reflectance from a solar PV panel must begin with a determination of the altitude of the sun (in degrees) relative to the ground. The "solar altitude" is the angle of the sun in degrees above or below the horizon. As such, the most important consideration when calculating light reflectivity is not the horizon, but the angle at which the solar panel is mounted relative to the horizon. 0 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 As the angle of the sun in relation to the solar PV panel increases, the angle of reflection will decrease and the altitude of reflection will increase. The altitude of the sun differs based on a number of different factors: the time of day, the season of the year, and the latitude at which the solar PV panel is located. 1.3.1 Determining the Vector Location of Incident Sunlight The sun's apparent path across the sky changes slightly every day in known and predictable ways depending on the location of the subject area on the earth and date of the year. At any given instant, the sun's position in the sky can be described by a directional vector characterized by an azimuth and an elevation. An azimuth is defined as the angle of the sun's position from due north in a clockwise direction. For example, if the sun rose exactly in the east and set exactly in the west, the azimuth of the sunrise would be 90* from north, and the sunset would occur at 270* from the north. The sun's elevation is defined as the degrees of the sun's orb above the horizon at any instant in time. Other azimuth conventions consider azimuth from north to south along the east half as ranging from 0° to 180°, and along the west half as ranging from 0° to -180'. Sun path chart diagrams plot the azimuth and elevation of the sun at any instant in time for any location on the earth. A sun path chart for the latitude and longitude of the proposed Project is shown in Figure 7. As depicted in Figure 7, the sun's path for a given date is shown in blue and the time during which the sun is at a specific location in the sky is shown in red. For the location of a given receptor such as a residence, the solar elevation and azimuth where reflections would be received at the receptor can be calculated and plotted on the solar chart. For example, for the hypothetical receptor shown in green, reflected light would only be received when the sun is between approximately 100° and 123° azimuth (from north) and at an elevation between 21° and 39'. From the chart, this would occur between 8 and 9 a.m, between the dates of March 20 to April 20. 1.3.1 Sunlight Geometry The determination and characterization of the geometry of incident and reflected light is a mathematical process that based on angles and vectors in three-dimensional coordinate systems. Light reflected from a surface is described in Figure 8a and shows that reflected light is symmetrical about the normal of the surface. All methods used to calculate the path of reflected rays use assume this symmetric condition. ■ i Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 00" 80" 70" SQ" 0 0 50o v L1 400 30" 200 100 30� 60" 90" l20" 150" 1f30" 210" 24 0" 270' 300, 330, 360, Fast C-- "301ar' Azimuth --> Nest. Figure 7: Solar Path Chart Plotting Solar Azimuths and Elevations as a Function of Time and Date for the Location of the Proposed Solar Project (X2 -Y2 -Z2) -n- u u—bplane 'i I \� S r 1lracking axis) Yvz1) N P(+) (aperture B, µ (tracking angle) normal) µ + tr b R '+r Collector aperture R Horizon (a) (b) Figure 8: (a) Geometry of the Reflection (1-2) of an Incident Ray of Sunlight (1-1) from a Vertical Reflective Surface (Source: Lillefair 1987). (b) Reflections from a Sloping Reflective 1 -Single Axis Tracker Surface. (Source: Stine and Geyer 2001) S, rlino,, n mo : I•C11C1C::::IC:C MEN MM ME i■■■■■ a'� ■■■■■■■� ■■. ■s C1�.NU ■�... WE I,MWISM■■ENNNwN/JffwA! i■■Z/IAFAI FAI0N■■■■■■B IHFA1 W, DOE ■i 30� 60" 90" l20" 150" 1f30" 210" 24 0" 270' 300, 330, 360, Fast C-- "301ar' Azimuth --> Nest. Figure 7: Solar Path Chart Plotting Solar Azimuths and Elevations as a Function of Time and Date for the Location of the Proposed Solar Project (X2 -Y2 -Z2) -n- u u—bplane 'i I \� S r 1lracking axis) Yvz1) N P(+) (aperture B, µ (tracking angle) normal) µ + tr b R '+r Collector aperture R Horizon (a) (b) Figure 8: (a) Geometry of the Reflection (1-2) of an Incident Ray of Sunlight (1-1) from a Vertical Reflective Surface (Source: Lillefair 1987). (b) Reflections from a Sloping Reflective 1 -Single Axis Tracker Surface. (Source: Stine and Geyer 2001) Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 Incident light of angle h1 and azimuth 01 is reflected across the normal at angle h2 and azimuth 02 where h2 = -hl and 02 = - 01. Note that the azimuth and angle of the reflected and incident light rays is relative to the normal of the example surface. Solar angles and azimuths from the solar path chart are based on a coordinate system that includes the plane of the earth's surface. Vector transformations are used to convert azimuths and angles from one coordinate system to another (Figure 8b). 1 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 2.0 DESCRIPTION OF THE PROPOSED PROJECT The Project proposes to use 2,862 SolarWorld Sunmodule SW 350 XL (350 W) solar PV modules. It will be built on a rooftop area of approximately 92,636 square feet and have an installed capacity of 1 MW. Modules will be stacked one high (landscape configuration) on a UNIRAC RM racking system spaced at 18-19 inches between modules (Figure 9). As installed, the modules will have an azimuth of 180°and a tilt angle of 10°. NOTE: ARRAY DIMENSIONS WILL VARY BASED ON MODULE WIDTH, LENGTH AND RETURN FLANGE TOP VIEW 155 77' 39' Nominal Module Dimensions Example 133" SIDE VIEW 13 6' 18' 19" Figure 9: Diagram of the Racking System Configuration for the Proposed Project 10 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 2.1 Geometric Characteristics of Photovoltaic Panel Configuration and Their Influence on Perceived Glint and Glare With respect to assessing the impacts of reflected sunlight associated with the PV modules for the proposed Werner Electric Rooftop Solar Project, the following considerations apply: 1. Perceived glint and glare are based on line -of -sight from the reflective surface. 2. The magnitude and duration of glint and glare reflections will be related to the height of the observer. When the height of the observer is less than 9 feet and the landscape is flat, only one reflecting rank of PV modules will be visible at a time. Modules south of the observer will be facing the opposite direction and oriented so as not to reflect light back to the observer. Most modules to the north of that directly opposite from the observer will be blocked from view by the visible rank. 3. Stationary receptors that are below the top height of the PV modules will only see glint and glare from those modules whose reflective surfaces are visible from that location. The glint and glare will move as the sun moves until the azimuth and elevation of the sun's rays are such that reflections are no longer received at the stationary receptor. 4. However, because the orientation of each rank is the same, each rank will reflect glint and glare at the same angle forthe same time increment and given azimuth and elevation angle of the sun. Thus, if a car with the observer at a height below the highest point of the PV rank observes a solar reflection, the same reflection at the same relative location will be observed as the car proceeds parallel to the PV ranks. 5. As the height of the stationary receptor increases above the height of the PV rank, progressively more of the area of adjacent ranks can be observed. At low heights, the majority of the PV panel area of successive ranks is blocked, but as heights increase progressively more of the reflective area of the full array becomes contributing. 11 Glint and Glare Study- Novel Werner Solar One Rooftop Solar Project August 18, 2017 3.0 IDENTIFICATION OF RESIDENCE- BASED KEY OBSERVATION POINTS Using satellite imagery and 3-d terrain models from Google Earth, a total of 22 residence - based KOPs were identified within 0.5 mile of the proposed Project. Due to the lowest possible reflection angle of 4' above horizon (see panel behavior), 0.5 mile is the threshold where reflections are projected high enough above the terrain to avoid KOPs within the Study Area (i.e., at 0.5 mile from solar PV arrays, reflections are 370 feet above the arrays). The locations of residence -based KOPs were determined from an examination of the direct line -of -sight between each of the residences and rooftop solar array. Viewpoints that were effectively blocked by buildings, topography, and trees and other vegetation were not considered in the analysis. For each KOP, a height of 6 and 18 feet was added to the overall ground height to simulate the average viewing height from the ground floor and second floor of a residence, respectively. The details regarding the identified KOPs are presented in Table 1, and the locations of the KOPs are shown in Figure 10. Table 1: Residence -Based KOP Details KOP No. Latitude (Decimal Degrees) Longitude (Decimal Degrees) Distance from Nearest PV Array Direction from KOP to Array 1 44.814364 N -92.959077 W 732 feet West 2 44.814119 N -92.958959 W 706 feet West 3 44.813987 N -92.958808 W 672 feet West 4 44.813749 N -92.95864 W 629 feet West 5 44.813612 N -92.958412 W 569 feet West 6 44.813443 N -92.958232 W 527 feet West 7 44.813246 N -92.958076 W 502 feet West -Southwest 8 44.813125 N -92.957846 W 460 feet West -Southwest 9 44.812954 N -92.957653 W 446 feet West -Southwest 10 44.812787 N -92.957453 W 443 feet Southwest 11 44.812625 N -92.957256 W 453 feet Southwest 12 44.812397 N -92.957125 W 506 feet Southwest 13 44.812142 N -92.957058 W 579 feet Southwest 14 44.811512 N -92.957244 W 809 feet Southwest 15 44.811518 N -92.956969 W 783 feet South -Southwest 16 44.811512 N -92.956709 W 768 feet South -Southwest 17 44.811515 N -92.956446 W 756 feet South -Southwest 18 44.811532 N -92.956154 W 744 feet South 19 44.811542 N -92.955852 W 741 feet South 20 44.811556 N -92.955629 W 736 feet South 21 44.811539 N -92.955266 W 742 feet South 22 44.811435 N -92.955061 W 781 feet South 12 Westwood .M • Residence KOP Project Boundary Solar Array N� Feet AO 200 ha Nerner Solar Project Cottage Grove, Washington County, M nnesota Residence KOP Locations Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 4.0 GLINT AND GLARE ASSESSMENT METHODOLOGY To evaluate the level and timing of potential Project -related glare on sensitive receptors, Westwood used Forge Solar's GlareGauge solar glare analysis software (formally the Solar Glare Hazard Analysis Tool (SGHAT). GlareGauge is a web -based tool that determines when and where solar glare can occur throughout the year from a PV array as viewed from specified observer locations. GlareGauge uses an interactive Google Maps interface together with a few user-specified parameters such as orientation and tilt of the modules to quickly locate a site, outline the proposed array, and calculate the occurrence, intensity, and size of the potential glare throughout the year. If glare is found, the tool calculates the retinal irradiance and subtended angle (size/distance) of the glare source to predict potential ocular hazards, ranging from a temporary after -image to retinal burn. It produces a color -coded display of the potential for the glare to result in an ocular impact. Once the area of the solar project is located and its design characteristics recorded, information on each of the glare -sensitive receptors must be input. Each of the residence - based KOPs is identified on the same map as the solar project as an observation point and the height of the observer is inserted. The inputs to the GlareGauge model are described in Tables 2-5 below. Table 2: PV Array Parameters PV Array(s) Name: PV array 1 Axis tracking: Fixed (no rotation) Tilt: 10.0 deg Orientation: 180.0 deg Rated power: 1001.7 kW Panel material: Smooth glass without AR coating Vary reflectivity with sun position? Yes Correlate slope error with surface type? Yes Slope error: 6.55 mrad Predicted energy output: 2,040,000.0 kWh (assuming sunny, clear skies) Tilt (of Tracking Axis) — Elevation angle of the fixed rack or tracking axis in degrees, where 0° is facing up and 90° is facing horizontally. The tilt angle of the proposed system is 10° on a fixed axis. Orientation (of Tracking Axis) — Orientation of the fixed or tracking axis in degrees, measured clockwise from true north. In this case the value was determined to be 180'. 14 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 Offset angle of Module —The vertical offset angle between the tracking axis and the panel. Maximum tracking angle—The maximum angle the panel will rotate in both the clockwise and counterclockwise directions from the zenith (upward) position. Rated Power (kW) — kW power of Solar PV plant. The DC size was used for inputs to this field. The DC size of the solar array for the proposed Project is 1,001.7 kW. Module Surface Material — Type of PV material used and surface finish of panel. According to specifications from the module manufacturer, it was determined that the input'Smooth Glass without ARC" would be the most accurate option. Reflectivity of PV module — The near-normal specular reflectance of PV glass (e.g., with AR coating) can be as low as 2%, the reflectance can increase as the incidence angle of the sunlight increases (glancing angles). This number is based on the values described in Table 3. Slope error — Mirror-like surfaces that produce specular reflections will have a slope error closer to zero, while rough surfaces that produce more scattered (diffuse) reflections have higher slope errors. Based on Manufacture's recommendation, a value of 6.55 mrad was used. Latitude and Longitude —_Latitude and Longitude of PV array boundary vertices. Used to define the area covered by proposed PV Array. In Table 3 below, latitude and longitude correspond to vertex ID's described on Figure 14. GlareGauge creates a reflective plane using these values for the glint and glare assessment. Ground Elevation — Elevation of vertices above sea level. Values are pulled into the table once the vertex is located. This is the point's base elevation. This value is used to 'shape' the reflective plane used to estimate glint and glare. Height above Ground— User input to modify/correct vertex elevation above ground. This point can be defined as 'PV array installation height above ground'. Since this project uses a fixed axis system an average value of 2 feet was used. Actual height averages 50 feet above ground because the PV array is installed on the roof of the Werner Electric building (see Figure 12). Total Elevation — Is calculated after adding the 'Ground Elevation' and "Height above Ground'. All units are in feet. Ground Elevation — Elevation of KOPs above sea level. Values are pulled into the table once the KOP is located. This is the point's base elevation. Eye level Height above ground — User input to modify/correct observer's elevation above ground. Input values used were 6 and 18 feet added to the overall ground height to simulate the average viewing height from the ground floor a nd second floor of a residence, respectively. 15 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 Table 3: PV Array Vertices Parameters Vertex Latitude Longitude elevation deg deg 1 44.814988 -92.956301 2 44.813516 -92.956303 3 44.813515 -92.955210 4 44.814002 -92.955212 5 44.814000 -92.955401 6 44.814988 -92.955403 Ground Height above Total elevation ground elevation ft ft ft 793.65 50.00 843.66 788.74 50.00 838.74 785.95 50.00 835.95 788.55 50.00 838.55 791.57 50.00 841.57 791.29 50.00 841.29 Figure 11: Map Showing Location of Vertices Used in GlareGauge Model Table 4: Residence -based KOP parameters 16 Glint and Glare Study -Novel Werner Solar One Rooftop Solar Project August 18, 2017 Discrete Observation Receptors Number Latitude Longitude Ground elevation Height above ground Total Elevation day deg ft ft ft 1 44.814364 -92.959077 812.63 6.00 818.63 2 - - _ 44.814119 -92.958959 812.75 - 6.00 818.75 3 44.813987 -92.958808 810.23 6.00 -� 816.23 4 44.813749 -92.958840 812.66 6.00 818.66 5 44.813612 -92.958412 812.27 6.00 818.28 6 44.813443 -92.958232 810.25 6.00 816.25 7 44.813246 -92.958076 811.63 8.00 817.53 8 44.813125 -92.957846 811.20 6.00 817.20 9 44.812954 -92.957653 813.54 6.00 819.54 1 10 44.812787 -92.957453 816.91 5.00 822.91 11 44.812625 -92.957256 816.21 6.00 822.21 - 12 44.812397 -92.957125 821.49 -- 6.00 - _ 827.49 13 44.812142 -92.957058 819.34 6.00 825.34 14 44.811512 -92.957244 - 816.07 -- 6.00 - -- - 822.07 -- 15 44.811518 -92.956969 816.87 6.00 822.87 16 44.811512 -92.956709 815.67 8.00 821.67 17 44.811515 -92.956446 813.68 6.00 819.69 18 44.811532 -92.956154 813.20 6.00 819.20 19 44.811542 -92.955852 812.63 6.00 818.63 20 44.811556 -92.955629 810.12 6.00 816.12 21 44.811539 -92.955266 808.00 6.00 814.00 22 44.811435 -92.955061 809.50 6.00 815.50 17 Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 5.0 GLINT AND GLARE RESULTS Results of the GlareGauge solar glare analysis determined that glint or glare would be visible at 10 of the 22 residence -based KOPs during a portion of the year. All of the glare would be low in intensity and classified as "low potential for temporary after -image", which is the lowest class of viewing hazard predicted by the model. Results for each KOP location are presented in Table 5. Table 5: Summary of Potential Glint and Glare Impacts on Residence -Based KOPs Eye -Level KOP above Glare Found? Time of Year Time of Day Notes No. Ground (ft) 1 6 and 18 Yes Low potential for Mar 15 — May 10 6 — 7:30 AM Both 15t and 2"d Story temporary after -image Aug 3 — Sept 25 2 6 and 18 Yes, Low potential for Mar 15 —Sep 25 6 — 7:30 AM Both 15t and 2"d Story temporary after -image 3 6 and 18 Yes, Low potential for Mar 15 —Sep 25 6 — 7:30 AM Both Vt and 2nd Story temporary after -image 4 6 and 18 Yes, Low potential for Mar 15 —Sep 25 6 — 7:30 AM Both 15t and 2"d Story temporary after -image 5 6 and 18 Yes, Low potential for Mar 15 —Sep 25 6 — 7:30 AM Both 15t and 2"d Story temporary after -image 6 6 and 18 Yes, Low potential for Mar 20 — Sep 20 6 — 7:30 AM Both 15t and 2nd Story temporary after -image 7 6 and 18 Yes, Low potential for Apr 1—Sep 7 6 — 7:30 AM Both 15t and 2"d Story i temporary after -mage 8 6 and 18 Yes, Low potential for Apr 7 —Aug 31 6 — 7:15 AM Both 15t and 2"d Story temporary after -image 9 6 and 18 Yes, Low potential for Apr 25 —Aug 15 6 — 7:00 AM Both 15t and 2"d Story temporary after -image 10 6 and 18 Yes, Low potential for May 15 —Jul 25 6 — 7:00 AM Both 15t and 2nd Story temporary after -image 11 6 and 18 None -- -- 12 6 and 18 None - -- 13 6 and 18 None - - 14 6 and 18 None - -- 15 6 and 18 None -- -- 16 6 and 18 None -- -- 17 6 and 18 None -- -- 18 6 and 18 None -- -- 19 6 and 18 None -- - 20 6 and 18 None -- -- 21 6 and 18 None -- -- 22 6 and 18 None -- - Glint and Glare Study — Novel Werner Solar One Rooftop Solar Project August 18, 2017 6.0 REFERENCES Capital Solar Farm Visual Impact Assessment (2010): Available at https://maiorprojects.affinitylive.com/public/a56f5ll3529f7O6lacb6deOcb400a52e/ Capita l%20EA%20Fina1%201.0%20Appendix%20F compressed- Part4%20.pdf Littlefair, P.D. 1987. Prediction of reflected solar dazzle from sloping facades. Building and environment 22(4):285-291). Sandia National Laboratories (Sandia). 2014. Solar Glare Hazard Analysis Tool (SGHAT) User's Manual, Ver 2D. Sandia National Laboratories. 34 pp. Stine, W.B. and M. Geyer. 2001. Power from the Sun. e -book Power from the Sun.net. 19