PV Panels on a vertical wall

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Bob Smith

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Hello

does anyone got any experince with PV Panels on a vertical wall.
I know that sounds strange but when trying to capture as much sun as possible and when the roof is already occupied with panels you start looking where else is getting the sun :)
I got a wall facing west and I thought I could capture some energy if I had panels there.
First I looked at the legality and found this

https://www.legislation.gov.uk/uksi/2015/596

1657785960841.png

It would therefore be OK if they do not protrude more than 20cm.

In term of how much energy they will produce, it is anyone's guess but as mentioned, why not add panels there this can only increase the total generation of electricity.

What do you reckon?

Thanks
Thanks
Bob
 
I am back online @binky :)

A few years ago (probably about 10 years) the Germany encouraged people to install panels facing East and West because they noticed that most of the electricity generated was around lunchtime and there was too much power, and of course in the morning or evening when the demand increases there was less supply.

While there is nothing that can be done for the electricity generated by the wind. It is a lot easier with the sun to place the panels in different directions.
While it is perfectly understandable why everyone wants their panels facing south for their first installation (unless some can afford to go full on and cover their house of panels at the first installation), regardless of having batteries or not, there will be more and more demand to install panels East, West, but also on walls to capture as much sun as possible.
You could also have wall installations with an incline to maximize the generation but with 20cm max protrusion allowed that is barely 5° while you will need at least 10° (or you need to install the panels horizontally)

We are talking about fixed panels of course. I hardly see anyone having a Follow The Sun PV system on their roof or back garden :)

PS: Another reason to have panels facing different directions is that throughout the day the sun won't shy constantly. If it is cloud at the best hours of the day and sunny either in the morning or in the evening, then with those additional panels you will capture more energy. I am stating the obvious here.
 
after the demise of the FiT, the original high tariff, East/West arrays became the 'new south' for the sales pitches. E/W gives a much better spread of useable power over the day, due South is best for generating FiT payments, but not the best for putting holes in your bills.

Horizontal panels are a bad idea, they gather to much dirt. I theory they will output 90% of due south at perfect pitch, in reality, you have to keep cleaning them to get anywhere near that. My own array is on a 5 degree garage roof, between birds and dust in dry weather I wash them at least once a month, weekly currently as I'm on the original high FiT rate, so I'm trying to maximise my earnings.

I have seen a few wall installations, mostly on industrial buildings. It has the added benefit of keeping the building cooler, but generally, peoples houses have too much shading from buildings / trees etc etc to make it a viable option.
 
after the demise of the FiT, the original high tariff, East/West arrays became the 'new south' for the sales pitches. E/W gives a much better spread of useable power over the day, due South is best for generating FiT payments, but not the best for putting holes in your bills.

Horizontal panels are a bad idea, they gather to much dirt. I theory they will output 90% of due south at perfect pitch, in reality, you have to keep cleaning them to get anywhere near that. My own array is on a 5 degree garage roof, between birds and dust in dry weather I wash them at least once a month, weekly currently as I'm on the original high FiT rate, so I'm trying to maximise my earnings.

I have seen a few wall installations, mostly on industrial buildings. It has the added benefit of keeping the building cooler, but generally, peoples houses have too much shading from buildings / trees etc etc to make it a viable option.
That's what I've gone for on two flat roof areas at the bottom of the garden - 18 panels (9 east/9 west).
It seemed more practical to spread the generation, over early morning and later in the evening, also meant I was able to maximize the number of panels which if sat south only would be 12 panels.
 
That's what I've gone for on two flat roof areas at the bottom of the garden - 18 panels (9 east/9 west).
It seemed more practical to spread the generation, over early morning and later in the evening, also meant I was able to maximize the number of panels which if sat south only would be 12 panels.
Hi 94JDH,
What type of flat roof was that? How have the panels being fitted? I have a flat roof but some installers are put off under the excuse that a structural survey will be required adding costs to the project..
 
Hi 94JDH,
What type of flat roof was that? How have the panels being fitted? I have a flat roof but some installers are put off under the excuse that a structural survey will be required adding costs to the project..
Hi Bob,

I have just replaced the old felt with EPDM rubber, the panels are not fitted yet (should be in around 4 weeks I hope). Renusol FS10 E-W Mounting system (not bolted through roof). The Survey didn't bring up any issues with the structure, they are 178mm x 52mm timber beams at approximately 400mm centres and are more than adequate for the support. I also doubled up the 18mm OSB3 board prior to install of the rubber, left the old ones apart from where water damage.
 
Another installer do not want to install panels on the wall (parallel to the wall). His excuse is that he needs different fitting and the cost will not be worth the efforts.

I am still puzzled by those installer. I cannot understand why they say things like this. In my little head I just need some aluminium support (surely the same used on the roof) that are screwed to the wall. Drill holes in the support if needs be. Then your panels are fixed the same way.
I think this is because those I talked too (4 so far), have never done it and simply can't be bothered to think.

The photo below shows how my PV panels were mounted on the roof in 2016.
Surely, when I see that I know I could take those aluminum bars and mounted them on a wall

1658502048240.png

What am I missing?
PS: I took the photo when they were putting them up, so no they do not extend over the house. What you see was not their final position.
 
what you are missing is suitable 'roof hooks' to attach those to a wall. All roofs hooks are dog legged to clear battens, so if you fixed those to a wall, it would look awful. i have, for a small ground array built a wooden frame to support the rails, and drilled the rails to insert wood screws through. But that is a non-standard installation, so would not be MCS compliant. Shletter do a mounting system for 'fascades', getting hold of it might be awkward as it's not a popualr installation method, ergo wholesalers tend not to stock it.

1658503575447.png
 
I quite like a little challenge job, keeps my engineering brain working. In this site it was not possible to roof mount, and the cutomer didnt want to see the panels, or a canopy type array, so I built a frame below a stone wall, consisting of unistrut cemented in the ground, added tie bars to the wall fixed in with chemical reasin and then bolted the panels to the unistrut.
 

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Hi @binky thank you for your messages

The suitable "roof hook" as you called it, for me it can either be a L bracket or you simply drill holes in the aluminum rail and bolts them to the wall.
You could also add between the wall and the rail or the bolt and the rail insolation material like a plastic washer or the like.


Regarding your first photo. I thought MSC compliance was about the electricity and not the "mechanical" part of the installation. This said, it must be strong enough to cope with the wind.

I like very much your second photo. Another example that shows nothing wrong with vertical panels. I note this is a Solis inverter. I did not know they made outdoor version.

Were those photos taken in the UK?
 
Thinking about what you have done with those vertical panels. This is actually pretty neat. I can't believe I am facing so much resistance from the installers in the north west. The bizarre thing is that they don't even mention planning permissions or legal constraints which shows they have no clue. Fortunately, I have the answer (see at the beginning of this post).
 

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