Glare poll

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Glare poll

  • No, unless required by law (i.e near airports)

    Votes: 7 100.0%
  • It depends on the size of the job and location.

    Votes: 0 0.0%
  • Yes, on every project.

    Votes: 0 0.0%

  • Total voters
    7
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jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
Poll:

Does your company do glare analysis on solar arrays prior to install?

Please give me your honest answers and your thoughts. :)
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
I did one once for an RFP response for a 3MW PV system on an airport property. It wasn't that big of a deal.
 

pv_n00b

Senior Member
Location
CA, USA
I've never had to do it. The only time I have seen a request for it was in an RFP for a feasibility study to determine if glare would be an issue for surrounding homeowners of a project being put in a state park. I think that project was a few hundred kW.

I have seen one or two residential installs that were set up just right to be a glare issue to neighboring properties and it would have been an issue with me if I had to live next to them and see that glare every day.

Typically glare studies are only called out within a certain distance from airports, but there is no particular reason that some AHJ could not make it an issue. If I were looking at 1000 3kW installs I would look at doing a typical study that could be applied to all of them to show the glare angle was such that it would not be an issue to others in the area as long as the neighbors were below the critical glare angle, which is typically high. That's why it's an airport issue and not usually a neighbor issue.

Here's some interesting articles if you want to be a glare knowledgable person. The quiz question of the day, What's the difference between glare and glint?

https://solarprofessional.com/artic.../evaluating-glare-from-roof-mounted-pv-arrays

And

http://solarindustrymag.com/online/...Glare-In-Dense-Residential-Neighborhoods.html
 
Last edited:

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Here's some interesting articles if you want to be a glare knowledgable person. The quiz question of the day, What's the difference between glare and glint?
I know that in computer graphics the inverse of the spread of the (simulated) reflected beam is called the "glint factor". The higher the glint factor the higher the intensity of the reflection but the narrower the beam. Mirrors have a very high glint factor.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
Okay, back on topic...:lol:

Typically glare studies are only called out within a certain distance from airports, but there is no particular reason that some AHJ could not make it an issue.

In California I believe the solar rights act protects the customer who has the solar system installed. I don't believe an AHJ would have grounds to make an issue of it. With that said, neighbors could sue (this is America!) for their putative loss of property value, or perhaps other grounds. And that could probably ultimately be a bigger headache than the AHJ.

If I were looking at 1000 3kW installs I would look at doing a typical study that could be applied to all of them to show the glare angle was such that it would not be an issue to others in the area as long as the neighbors were below the critical glare angle, which is typically high.

I think you are making this sound a lot easier than it is. What would be the parameters of typical? I would need one 'typical' study for the city, another for the suburbs. And then I would need to figure out how to insert that into my company's design process to make any use of it, while trying not to increase the duration and difficulty of the process more than it's worth.

Here's some interesting articles if you want to be a glare knowledgable person. The quiz question of the day, What's the difference between glare and glint?

https://solarprofessional.com/artic.../evaluating-glare-from-roof-mounted-pv-arrays

And

http://solarindustrymag.com/online/...Glare-In-Dense-Residential-Neighborhoods.html

Thanks, I had found the first one already but not the second one.

The software I've been using to evaluate our problem install is at www.forgesolar.com. It used to be free from Sandia National Lab, but they privatized it last month.
 

pv_n00b

Senior Member
Location
CA, USA
Okay, back on topic...:lol:

In California I believe the solar rights act protects the customer who has the solar system installed. I don't believe an AHJ would have grounds to make an issue of it. With that said, neighbors could sue (this is America!) for their putative loss of property value, or perhaps other grounds. And that could probably ultimately be a bigger headache than the AHJ.

The Solar Right Act only protects a person's PV system from being shaded after it has been installed and from some HSA objections to PV systems in HSA controlled subdivisions. It does not specifically cover if I protest my neighbor's PV system building permit with the city building department because I think it will put glare on my property.

I think you are making this sound a lot easier than it is. What would be the parameters of typical? I would need one 'typical' study for the city, another for the suburbs. And then I would need to figure out how to insert that into my company's design process to make any use of it, while trying not to increase the duration and difficulty of the process more than it's worth.

I don't know what your particular project is. I was thinking if you had a single housing development with 1000 homes that you could find the most probable arraignment of homes in that development that would result in glare and show that it could not happen. If it did not happen there then it would not happen in other parts of the development.

If what you are really dealing with is an AHJ that requires a glare study for every PV system in their area that is something else. You could still do a typical that shows for a range of common roof angles in the area that the property receiving glare would have to be above a certain elevation, at a certain distance, in a certain direction from the PV array. Properties not in this area could not experience glare from the PV system. Just an idea.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
The Solar Right Act only protects a person's PV system from being shaded after it has been installed and from some HSA objections to PV systems in HSA controlled subdivisions. It does not specifically cover if I protest my neighbor's PV system building permit with the city building department because I think it will put glare on my property.

You may be right, although I'm not aware of any case law on this particular question. Not that I'm a lawyer. (Are you? ;))

I don't know what your particular project is. ...

It's not a particular project. We do residential solar. Just think if you had 1000 projects, 1000 customers, 1000 locations, 10000 neighbors, etc...

If what you are really dealing with is an AHJ that requires a glare study for every PV system in their area that is something else.

I'm dealing with an angry neighbor of a customer whose system is already installed. The neighbor insists we should have known there would be glare. The AHJ is not directly involved at this point.
 

pv_n00b

Senior Member
Location
CA, USA
We all know the answer to this one, glare studies are not a normal part of a PV installation, any more than they are part of a window installation, or a pool, or any one of a hundred home construction projects that could cause glare. I have not heard of any rumblings about making glare studies standard for all PV installations from any AHJs.

That being said it's worth a happy neighbor finding a solution to mitigate the problem for this specific install. Glare is incredibly irritating. I get it in my office window when a guy parks his truck in a particular spot and it drives me crazy.
 
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