Solar upgrade! Got 200W on my roof

tee_cee · 2022-03-21 12:52:22

Finally got round to buzzing out my 60W failed panel (the 100W is probably lying at the side on the M6 somewhere).
So the cells are connected to each other with thin "tabbing" wire (busbars), across the top of the cell and then underneath the next cell.This video shows the contruction https://www.youtube.com/watch?v=Wu8JngRM-UA So for the panel to go open circuit it would mean all the wires between 2 adjacent cells would have to fail. My cheapo panel only had 2 wires between the cells. The failure I found was at the transition between 2 cells.
Anyway I would expect that the more busbars the less likelyhood that all would fail - though I would suspect that there will be some voltage drop with each failure.

There are newish flexible stick down panels on the the market now using CIGS technology. They do not heat up in use, and have loads of bypasss diodes the reduce shading effects. Also very expensive - £380 for 170W panel. Also worth noting that they seem to operate at higher voltages (50V with the 170W) for, so a new inverter may be needed.

At the moment I need to fit something for minimum effort so I'm back to a semi-flexible again. Trying to fix the perlight panel mentioned before will be just to difficult - at 1m x 1.5m and 17kg, I would not want to see this fly offf my roof.

Casper · 2022-03-21 21:37:14

Got to love Solar. Got my bus back yesterday from three month storage in a cold soggy field. Solar as well as leisure battery has been looking after the starter battery also. Fired into life first turn of the key.

Got a Maxus as a work van and going to add 100w panel into that later in the year as they are bad for battery drain when not getting used. Also looking to stick in a small inverter to charge my power tool batteries.

Pathfinder100 · 2022-03-22 02:43:11

tee_cee wrote:

At the moment I need to fit something for minimum effort so I'm back to a semi-flexible again. Trying to fix the perlight panel mentioned before will be just to difficult - at 1m x 1.5m and 17kg, I would not want to see this fly offf my roof.

That's what bolts and brackets are for. tongue Although I do hear you on that. I abandoned the Perlight panel idea and am planning on putting a second 100w panel on the roof in the next couple of months. My intention is to bolt them together and also through the roof. At present the 100w panel that is up there for now is held on with Stixall, which was supposed to be a stop gap for a couple of months, but turned into a longer term bodge.

Your new panel sounds like some panels they had at Bimble about a year back. A 100w panel was able to push out an OC voltage over 110V at 5A (or roundabouts that). I was kind of interested in getting a couple for my van, but my MPPT has a max VOC of 100V. Would have needed a new controller to accommodate them.

As for needing a new controller for a 170W panel with a VOC of 50V, the Budget 20A Epever XTRA would be fine. It has a Max VOC of 60V and can accommodate upto 260w of panel, all for £55. Or the 15A Victron would do the same, if you are already invested in Victron kit.

kenbw2 · 2022-03-22 14:10:05

Pathfinder100 wrote:

tee_cee wrote:
At the moment I need to fit something for minimum effort so I'm back to a semi-flexible again. Trying to fix the perlight panel mentioned before will be just to difficult - at 1m x 1.5m and 17kg, I would not want to see this fly offf my roof.
That's what bolts and brackets are for.

Agreed! I've seen lots of people advocate for gluing panels on the roof, I'd be way too scared to trust that glasses

Pathfinder100 · 2022-03-22 15:34:43

I think it also depends on the panel. The 100w I have up at the minute weighs about 8KG and the Stixall I used should be fine for now. I've used it to glue a lot heavier things and never had a failure. Now if it was a 300-400w panel, yeah I would have bolted it down as well. But i knew this panel would be replaced at some point, so no point doing a permanent job.

Most people who have failures seem to use Sikaflex (and probably the wrong one).

kenbw2 · 2022-03-22 20:14:38

Haha I wasn't say glue wouldn't hold, just that I'm not brave enough to use it!

I managed to attach mine to the existing roof bar mount points with bolts, so still semi-permanent

Casper · 2022-03-23 08:20:38

Pathfinder100 wrote:

Most people who have failures seem to use Sikaflex (and probably the wrong one).

I know people who stick panels down using Sikaflex with no issue. One person in our self build group used the cheap Sika out B&Q and that is fine also where he drives like he stole it. As long as you stick it on clean surfaces it should be great. When i got my bus the panel was stuck down side ways and would hang over the edge. That was Sikaflex also and needed a carving knife to remove it but personally i use brackets for the sake of air flow.

Pathfinder100 · 2022-03-23 12:35:46

I actually meant more along the lines of how their are many types of Sikaflex and not all are ideal for sticking things down. Using the wrong one could lead to failures.

If you use one that is correct for the application, then yes, it will probably work very well.

Saying that, the paint on my van is very suspect, so that might be a failure point for me. I was washing it and a big strip came off the back door, right down to undercoat. Hopefully the roof isn't as bad.

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#26 2022-03-21 12:52:22

Re: Solar upgrade! Got 200W on my roof

#27 2022-03-21 21:37:14

Re: Solar upgrade! Got 200W on my roof

#28 2022-03-22 02:43:11

Re: Solar upgrade! Got 200W on my roof

#29 2022-03-22 14:10:05

Re: Solar upgrade! Got 200W on my roof

#30 2022-03-22 15:34:43

Re: Solar upgrade! Got 200W on my roof

#31 2022-03-22 20:14:38

Re: Solar upgrade! Got 200W on my roof

#32 2022-03-23 08:20:38

Re: Solar upgrade! Got 200W on my roof

#33 2022-03-23 12:35:46

Re: Solar upgrade! Got 200W on my roof

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