What do other communities do to mitigate the effects of glare from solar panels on surrounding properties?
One of the major tensions in regulating solar energy systems is the potential tradeoff between system optimization and aesthetic effects on surrounding properties. In practice, the amount of glare depends not just on the angle of installation but also on the specific product installed. Different types of solar panels absorb different amounts of light. Newer panels generally include at least one anti-reflective layer to maximize absorption and minimize glare. In fact, the reflectivity of solar panels is often much lower than that of other nearby materials (e.g., standard glass, snow, or steel).
When communities address glare in their development standards for either rooftop or freestanding panels, the language is typically subjective. In other words, the standards usually say that systems must be designed and sited to avoid glare on adjacent properties or roadways without going so far as to require a glare study or specific glare mitigation techniques or technologies.
Examples of Development Standards that Address Glare
Albany (New York), City of. 2011. City Code. Chapter 375. Zoning. Article XIV. Specific Use Regulations. Section 375-93. Solar energy equipment.
- “Ground-mounted solar collectors are permitted as accessory structures in all zoning districts, subject to the following requirements: (4) The solar collectors do not emit unreasonable glare and negatively impact adjacent properties.”
Calabasas (California), City of. 2011. Municipal Code. Title 17. Land Use and Development. Chapter 17.20. General Property Development and Use Standards. Section 17.20.190. Solar Energy Development Standards.
- “Exterior surfaces of the collectors and related equipment shall have a non-reflective finish and shall be color-coordinated to harmonize with roof materials and other dominate colors of the structure.” (Section 17.20.190.D)
Dundee (Michigan), Township of. 2010. Ordinance No. 09-10-01: Solar Panel Zoning Ordinance Amendment.
- “Glare. Solar panels shall be placed and arranged such that reflected solar radiation or glare shall not be directed onto adjacent buildings, properties or roadways.” (Section 5.22.3)
Lincolnshire (Illinois), Village of. 2011. Municipal Code. Title 6. Zoning. Chapter 17. Alternative Energy Collection Systems. Section 6-17-6. Solar Energy Systems (SES).
- “Shall be designed and installed to prohibit Sun Reflection towards vehicular traffic and any habitable portion of an adjacent structure. Sun Reflection onto an adjacent roof shall be acceptable.” (Section 6-17-6.C.1.c)
Shoreham (Vermont), Town of. 2004. Zoning Bylaws. Section 341. Conditional Use Review. Subsection G. Performance Standards. Section 527. Solar and Wind Energy Systems.
- “No glare, lights, or reflection shall be permitted which are a nuisance to other property owners or tenants or which could impair the vision of a driver or any motor vehicle or which are detrimental to public health, safety, and welfare. However, reflections from solar energy collectors which are part of an operating solar energy system shall not be considered a nuisance to other property owners and tenants.” (Section 341.G.2)