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Advice sought on mounting hardware & design for solar [single] car canopy

morrisga2000

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Aug 3, 2022
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This concerns finding appropriate mounting hardware like rails and brackets for a DIY solar car canopy (=partial carport) to go with two Renogy 450W panels. I am hoping to keep this as a single pole, top-of-pole mount configuration. My thought is that I will have to make this some mixture of lumber and unistruts, but I would prefer aluminum/steel construction and to minimize the use of wood, as the alleyway beside my parking pad gets very strong winds in the winter. Does anyone having any experience with or recommendations for metal framing struts to use as solar panel mounts for an above-ground installation such as this? Is there a preferable gauge size?
I got the Mars Solar V2 Solar Panel Rack Mount, but I realize this item is likely only intended to handle one panel of the size that I have. Side note -- This was because I was originally intending to only go with 400 Watts total, but Renogy was out of stock of my desired panels when it came time for me to purchase something. And I thought I was instead getting 450Watts, as Renogy often labels the total output in its ads, but not in this case, as it was per panel. Oops!
I would rather orient these panels in a portrait orientation. Approximate dimensions of the two PV panels together is 7.5ft wide by 6 feet tall. This mounting system (the solar canopy) is to be located beside my backyard fence, over my rowhome's parking pad. The Renogy panel-frames are just shy of 1&1/2 inches thick, if that helps any with sizing and fit.
Any constructive advice on what I should get and how I should assemble mounts for this size system -- not small but not commercial-scale large -- would be greatly appreciated.
I am new to this, and wanted something that could help power my electric vehicle in the immediate term, and then later grid-connect it to power my HVAC and lights.
Resources? Products? Thank you!
 
If you are pulling a building permit you will need an engineer to sign off on plans. Alternately you can get stamped plans using the tools on rack manufacturers like Ironridge, Unirac and others. Those are multiple pole ground mount systems. My recollection from trying one of those design tools was the fewer poles which were used for an array the bigger the required poles were and the more concrete was needed because the holes needed to be deeper and bigger. There was definitely an optimal design from a cost standpoint. I don't even think there was a single pole mount but maybe there was for two panels.
I can tell you that after charging EVs with grid tie solar for ten years on four different houses, you will soon need or want a much larger system unless your EV is a golf cart. Think in terms of kiloWatts not Watts. The typical EV uses one kWh for every every 3 or 4 miles driven. My first system was 3 kWs and now I have 9 kWs. It generates 45 kWhs in summer and 15 kWhs in winter.
 
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This concerns finding appropriate mounting hardware like rails and brackets for a DIY solar car canopy (=partial carport) to go with two Renogy 450W panels. I am hoping to keep this as a single pole, top-of-pole mount configuration. My thought is that I will have to make this some mixture of lumber and unistruts, but I would prefer aluminum/steel construction and to minimize the use of wood, as the alleyway beside my parking pad gets very strong winds in the winter. Does anyone having any experience with or recommendations for metal framing struts to use as solar panel mounts for an above-ground installation such as this? Is there a preferable gauge size?
I got the Mars Solar V2 Solar Panel Rack Mount, but I realize this item is likely only intended to handle one panel of the size that I have. Side note -- This was because I was originally intending to only go with 400 Watts total, but Renogy was out of stock of my desired panels when it came time for me to purchase something. And I thought I was instead getting 450Watts, as Renogy often labels the total output in its ads, but not in this case, as it was per panel. Oops!
I would rather orient these panels in a portrait orientation. Approximate dimensions of the two PV panels together is 7.5ft wide by 6 feet tall. This mounting system (the solar canopy) is to be located beside my backyard fence, over my rowhome's parking pad. The Renogy panel-frames are just shy of 1&1/2 inches thick, if that helps any with sizing and fit.
Any constructive advice on what I should get and how I should assemble mounts for this size system -- not small but not commercial-scale large -- would be greatly appreciated.
I am new to this, and wanted something that could help power my electric vehicle in the immediate term, and then later grid-connect it to power my HVAC and lights.
Resources? Products? Thank you!
Definitely requires an engineer to design it. I know Versatube has carport designs that can support solar panels, and they do custom designs with full engineering approvals. It's reasonable at around $4k-$10k depending on the size of the structure.

However, a cantilevered solar carport is "the most expensive and unforgiving structure" you could choose to DIY. Force x Distance, the pole is tall above the ground, the solar panels are a giant wind catcher and even at minimal wind speed, the forces will be multiplied to tens of thousands of pounds. It requires a concrete bollard as you see for 40-ft parking lot light posts, that goes deep into the ground. Cantilevered carports typically use 8" to 12" steel I-Beams or Box channels for the post. It's hugely expensive unless you're a welder by trade. Wood for tall structures in the open wind is not advisable. If you have a spot that is well protected from high winds from all sides, my concerns are unwarranted. In my own yard, however, it wouldn't last a week.
 
If you are pulling a building permit you will need an engineer to sign off on plans. Alternately you can get stamped plans using the tools on rack manufacturers like Ironridge, Unirac and others. Those are multiple pole ground mount systems. My recollection from trying one of those design tools was the fewer poles which were used for an array the bigger the required poles were and the more concrete was needed because the holes needed to be deeper and bigger. There was definitely an optimal design from a cost standpoint. I don't even think there was a single pole mount but maybe there was for two panels.
I can tell you that after charging EVs with grid tie solar for ten years on four different houses, you will soon need or want a much larger system unless your EV is a golf cart. Think in terms of kiloWatts not Watts. The typical EV uses one kWh for every every 3 or 4 miles driven. My first system was 3 kWs and now I have 9 kWs. It generates 45 kWhs in summer and 15 kWhs in winter.
Thank you for the input. In my case, I work from home over 90% of the time, and maybe need to drive 3 to 5 miles per day on average. So, generating 3.5 to 4kWh per day is fine with me. Yet there is the possibility to expand my system to maybe twice as much on the adjacent walls of my small yard. I am trying to keep this as DIY and low-cost as possible, so spending over $3K for a pre-fab system intended for two to four cars is not what I am going for.
I completely understand what you are saying about structural strength and stability, and will see what kind of solar engineer I can find. The problem with where I live, is that if I so much as mention my zip code and area, quoted prices immediately start doubling and tripling what they should be.
 
will see what kind of solar engineer I can find.
Solar engineer? That is probably more expensive than a structural engineer. As a practical matter it will be a challenge to pull off without a grid connection. Most charging interfaces do not deal well with variable current. When I say interfaces I mean both the EV and the EVSE. It is not trivial but give it a try and report back. There seems to be an interest in such an application.
 
Solar engineer? That is probably more expensive than a structural engineer. As a practical matter it will be a challenge to pull off without a grid connection. Most charging interfaces do not deal well with variable current. When I say interfaces I mean both the EV and the EVSE. It is not trivial but give it a try and report back. There seems to be an interest in such an application.
I used the term "solar engineer" merely to refer to someone that is familiar with installing structures for solar/PV purposes. A structural engineer will suffice I am sure. As for the grid connection, I will have a grid connected level 2 charger as well nearby. And I have an inverter and large battery for safe energy storage from the solar panels. I tried to learn what I could from Will Prowse's videos and these forums about solar system setup.
 
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