Commercial Solar - System components at scale

[ARCdesign]

I am new to solar panels and working with a team on the schematic design for a client entertaining the idea of adding a large amount of PV panels to their project.

I have two questions:

For large-scale commercial projects, what components are required for a PV system (aside from the panels themselves), and how much space do they take up?

I have found many online tools in my search that will help determine the output of an installation based on area and show me the approximate angle and orientation for solar panels based on the project location however I have not been able to determine the physical space the other components will take up on the site or in the building.

I was hoping for a formula of sorts, such that if I had 270,000 sq. ft. of the roof then I would need to set aside an electrical room of (x) sq. ft. for the transformers and breakers or any other equipment.

Currently, they are discussing adding solar panels to the roofs of two different buildings on the site and potentially adding more panels in the surrounding surface parking.

Roof areas-

Building 1: 270,000 sq. ft.
Building 2: 220,000 sq. ft
Surface Lot: 20,000 sq. ft.

I have reached out to a few commercial installers but I have not gotten a response, and I am really only looking for a rough number for space planning purposes.

I believe the inverters could be decentralized and put on the roof with the panels, but there would still be space requirements for transformers and breaker boxes and I am not sure if there are other components I am not aware of.

Generally, I would think these elements could be incorporated into a standard-sized electrical room, but because there is a potential for over 500,000 sq. ft. of solar panels I am not sure.


Thank you for any assistance you may be able to provide.

[Mike 134]

Wow if those panels are say, 405W each you could possibly have close to a 9 MW system with 500K Sq Ft of space. You have electrical engineers for buildings this size already on board what are their thoughts? I just happened to read about a smaller system than yours yesterday perhaps you're on the east coast and can contact these folks.
Sonoco turns on 1 MW rooftop solar array at New Jersey warehouse – pv magazine USA (pv-magazine-usa.com)

[ARCdesign]

Thanks, I will look into this. And, yes there are many other people on this project that will weigh in as we progress. However, because things are so ambiguous... they are looking for direction (and to see how much funding the client can secure) so this is still sort of just an exercise and ballpark estimates are all we are trying to get.

[ARCdesign]

I calculated with PVWatts and came up with an approximately 7.2 MW system, combining the three areas. But even using SAM I am not familiar enough with the program to know if it provides the information I require.

[J.P.M.]

Best assistance or advice I can provide is for you and your bosses to find a good engineer who knows a lot about solar energy engineering and is also an experienced project engineer and pay the going rate.

The landscape is littered with PV projects started in ill-conceived ignorance.

This is not the right format for all the issues that need to be discussed in depth. That you may think so is a good indication of your experience.

[fraser]

Spend your time researching low cost commercial vendors/installers. Everyone of them will give you a quote as they want this type of business. Also consider going direct to the manufacturer.

[Calsun]

You need to find an electrical contractor with experience with large commercial solar installations. You do not even know what questions to ask or what considerations are important, in particular with moving AC versus DC current over distances and the related NEC safety code.

I would want a contractor with the best record for design and build and by no means the people that submit the lowest bid. Equipment costs are going to be the same and the labor is the same and the labor rate with qualified union electricians will be the same. The only way to have a significantly lower quote is if the contractor plans to cut corners or does not fully understand the scope of the project and is likely to bail before the work has been completed.

[ARCdesign]

Thank you, I appreciate all the feedback, I am not pretending to be an expert or provide my colleagues with specific information but due to the nature of this project and the early stages we are in, developing concepts and space planning is something our client is specifically looking for. I agree that in the actual planning of this specific installation, it would be better to work with a specific installer and electrical contractor to determine exactly what would be required that however was not the brief we were given. The work that we are doing is merely to propose ideas and I would like those ideas to be doable. I have contacted many commercial installers, but many have not gotten back to me, and few have been able to provide me with information when I can not provide specific information about the project past what I have explained here.

[J.P.M.]

Thank you, I appreciate all the feedback, I am not pretending to be an expert or provide my colleagues with specific information but due to the nature of this project and the early stages we are in, developing concepts and space planning is something our client is specifically looking for. I agree that in the actual planning of this specific installation, it would be better to work with a specific installer and electrical contractor to determine exactly what would be required that however was not the brief we were given. The work that we are doing is merely to propose ideas and I would like those ideas to be doable. I have contacted many commercial installers, but many have not gotten back to me, and few have been able to provide me with information when I can not provide specific information about the project past what I have explained here.

For the size project you seem to be describing, you need something larger than an installer as that term commonly implies. That may be why you keep getting blown off.
You need an engineering and/or construction company.
Since it looks to me like you don't know any more about what's required than your client does, why not do the right thing and tell your client to do the search and contract the work themselves.

Or, have them read this thread.

[ARCdesign]

For the size project you seem to be describing, you need something larger than an installer as that term commonly implies. That may be why you keep getting blown off.
You need an engineering and/or construction company.
Since it looks to me like you don't know any more about what's required than your client does, why not do the right thing and tell your client to do the search and contract the work themselves.

Or, have them read this thread.

I appreciate the insight but worry not. I am not the project manager for my team on this project, and you are correct that I do not know what is required - which is why I am asking.
I am working for a sub-consultant to a larger group of companies and contractors, and this is obviously not my area of expertise - I am an architect in training, doing the tasks that I am asked to do - I am not privy to most of the conversations on this project, but I was happy to find this forum and learn more about projects similar to what we are working on.

I have contacted larger commercial installers that have installed projects for power companies and municipalities much larger than this, and while I have not been able to discuss the specifics while on my fact-finding mission, they have helped to provide some information that I am passing along. Your grave warnings and suggestions are also very appreciated.

[J.P.M.]

Your grave warnings and suggestions are also very appreciated.

Not so much grave but based on reality and an engineering career that included large project management. Be careful you don't do some damage.