mounting brackets for metal garage roof

[xcentric]

Have standard size solar panels to fit onto my castellated metal garage roof - shown below.

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Single storey roof, typical UK inland conditions (I.e. not generally too windy but the occasional storm coming through in winter).

Want them to be able to be adjustable tilt. Have all brackets and fixings to join all panels together in one long unit. Panels are 24.5kg each.

Thinking I don't need a frame along the roof itself (as sold for ground mount systems) as will be tapping into the metal and often down into the wood supports beneath, so just need to hinge them at the bottom and support them at the back.

Any recommended hinges? solar-type ones that attach into the alu cross brackets


or simple hinge attached to solar panel frame at bottom?


Do I need vertical struts joined to the cross bars as per below
- and if so do I need 1 per panel, one per 2 panels, 2 per panel? Will too few make it flex too much, or does the all cross beam stop this (it's the usual dual channels at rights angles to each other stuff.). Can I just put supports onto the cross struts?

Also trying with hinges of some sort at bottom and linear actuators (prob 3) to push panels up and down according to time of year - each actuator can push 300kg and 8 panels are ~200kg.

Looking for effective, secure, cheap DIY approach......

 

[mentler2]

I'm no expert, but it looks like you've been waiting awhile, so I don't mind sharing my opinion.

Regarding type of hinge:
In this context, metal is metal. The wind/rain/snow forces on any given panel aren't going to be high enough to cause a hinge to fail. I imagine fasteners will fail before most hinges. Personally though, I'd probably avoid repurposing cabinet hardware. That might be encroaching on dubious territory.

Regarding vertical struts:
If I'm understanding the part of the diagram you're referring to correctly, I don't think the vertical struts are necessary for mechanical stability. The panels will flex a bit without reinforcements under a strong wind, but the panels are designed to handle those sorts of loads.



I'm curious about how you plan to mount your actuators. My understanding is that most people at latitudes between -56°
and 56° latitude will want to utilize the fullest pitch of their roof at some point in the year. I can't currently imagine a way to mount actuators without sacrificing at least a bit of pitch.

 

[xcentric]

fixing onto metal garage roof, so thinking I can have hinge from bottom of panel to roof, and struts from top to roof as well. Cost of actuators more per kW improvement than additional panels, so going for manual (3 position) approach, or maybe even fixed for simplicity.

 

[mentler2]

Yeah, fixed seems to be the typical strategy. Panels are cheap enough now that if you want to increase your wattage the most economical option is usually to simply add more panels to the array.

However, if you happen to be limited by the surface area of your roof, like I am, incident angle tracking is the only option for squeezing more watts out of the array.

 

[teal95]

My barn roof is 4-12 pitch and the ridge runs north-south. I just covered the roof with panels. It wasn't worth the effort to angle them. As a benefit the flatter they are the better they produce when it's overcast.