Solar Panel Glare: Is it an Issue?
How much glare comes from solar panels?
Solar panels generate power by absorbing light, so any light reflected is energy wasted. To avoid this waste, most solar panels have textured glass and anti-reflective coating that reduces glare. Most solar panels today have less potential for glare than windows from vehicles or residential and commercial buildings.
How do we know if glare will be an issue?
Consulting firms that conduct glare studies usually rely on the glint and glare standards and software created by the Federal Aviation Administration to judge the potential for glare. These studies look at various points of interest, such as points on nearby roadways or neighboring houses. The impact on these points of interest is shown by the time in minutes per year and by the intensity of the glare measured.
The intensity of the glare is put into three categories. Green glare may cause eye strain if someone is exposed to it for a lengthy period. Yellow glare will cause one to squint and impair vision. Red glare can cause permanent eye damage. Solar panels cannot produce red glare, and most glare studies either find no glare or green glare is produced.
What can be done if glare is found to be an issue?
Suppose a glare analysis finds that panels will produce significant amounts of green or yellow glare. In that case, developers can adjust the placement or the panels' angles to address the issue. Requiring that a developer perform a glint and glare study and address any concerns of significant glare found in the study is the best way to prevent glare. Screening can also work to reduce the potential for glare since glare is only possible when one can see the panels. It is recommended that if zoning ordinances are put in place, the ordinances should put the burden on the developer to eliminate or reduce glare.
In conclusion, glare is a potential issue with panels, but in most cases, it will not be a problem for those who live by or travel by a solar array. To prevent the potential impact of glare, a municipality should make a provision in its ordinance to require developers to prove that the solar array will not produce significant glare on neighboring properties and public roads.
