We have 2 x 120w solarking panels on our poptop, seems like one is now faulty, and of course I that exact size one is not available now.

so it looks like I will need to replace both panels, we only use about 25 amps overnight from our 100 amp lithium, so anything from 240 to 300 watts is ample for us (were inWA, so lots of sun generally), what panels do people recommend, Im thinking of these new Renogy panels, but not sure if I really need them at the cost and the advantages I might get.

https://au.renogy.com/renogy-200w-shadowflux-anti-shading-n-type-solar-panel/?Rng_ads=56cd787036485d32&kw=&ad=&gr=&ca=22150515033&pl=ga&gclid=CjwKCAjwvuLDBhAOEiwAPtF0Vqmf1MMw2ddW9HY4XcORFw_lPtSt-QBC2ST-6fFMH9M85PSIC6aABhoCK-cQAvD_BwE&r_u_id=1912567345&gad_source=1&gad_campaignid=22150520040&gbraid=0AAAAADJwR9IRxGuMAR0C7LcF6-3ZzRQJO

also, is there any secrets to removing the current panels? Ive attached pictures to show the silastic etc..

Brianvicki wrote:

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We have 2 x 120w solarking panels on our poptop, seems like one is now faulty, and of course I that exact size one is not available now.

so it looks like I will need to replace both panels, we only use about 25 amps overnight from our 100 amp lithium, so anything from 240 to 300 watts is ample for us (were inWA, so lots of sun generally), what panels do people recommend, Im thinking of these new Renogy panels, but not sure if I really need them at the cost and the advantages I might get.

https://au.renogy.com/renogy-200w-shadowflux-anti-shading-n-type-solar-panel/?Rng_ads=56cd787036485d32&kw=&ad=&gr=&ca=22150515033&pl=ga&gclid=CjwKCAjwvuLDBhAOEiwAPtF0Vqmf1MMw2ddW9HY4XcORFw_lPtSt-QBC2ST-6fFMH9M85PSIC6aABhoCK-cQAvD_BwE&r_u_id=1912567345&gad_source=1&gad_campaignid=22150520040&gbraid=0AAAAADJwR9IRxGuMAR0C7LcF6-3ZzRQJO

 

also, is there any secrets to removing the current panels? Ive attached pictures to show the silastic etc..

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 I have two Renogy on my roof 100W each for the engine battery, and in all honesty the best wattage I got since day one was of 137 watts combined.. They are installed same way as all the other panels (Sunpower) I got, but the other panels have always given me a much more realistic wattage, as in close to the wattage rating of the panels.. You do as you wish with this info..

To remove the corner from the roof, there is only one way and it is mechanical. First remove the panel from the plastic mounting corner, then gently start to cut the silastic bit by bit with a good 25mm sharp blade. If cleaned properly, you can easily re-use those plastic mount..

Most silastic are removable only by mechanical mean. There are no chemical or trick of the trade available..

EDIT:

Also remember that the surface where the silastic will go and the thickness of the silastic are very important.. For instance Sikaflex, recommend a minimum thickness of 5-10mm of beed and not to be press down all the way, so to retain the elasticity required in such installations. They also recommend priming the ABS plastic mount with Primer Sika 215 to assure maximum adhesion to the plastic and Primer Sika 206 G+P for the actual roof..

Good luck..

A little surprising to see Burt's comment not being happy with Renogy. The brand has a reputation for quality (as does Sunpower), although I have no first hand experience of either to relate. Whatever you choose, check the dimensions and claimed watts. Particularly on ebay some sellers are quoting outrageous figures.

I note the linked panel quotes 25% efficiency but in the specs it refers to module efficiency of 20.7%. The difference is the first one relates to each cell in lab conditions, while module efficiency is the whole panel including frame and space between cells. 20.7% is good, but not leading edge. It seems to be priced about right for that.

I have a Jaycar 120 watt panel purchased 2012 and still performing fine. Then in 2018 I bought an ebay one quoted at 200 watts. I knew by its size it was overrated and I calculated 150 watts. When mounted, it did produce a bit more than the 120 watt Jaycar. But after a couple of years I could see fine cracks in the silicone. Now it has dropped to below the 120 watt Jaycar. Quality matters.

As for the mounts, I am not a fan of the plastic mounts. I came close to losing a panel where the mounts had degraded and cracked due to UV exposure in less than 2 years. Also, when you remove them, look underneath at the small surface area for adhesion. I replaced them with galvanised brackets.

Bunnings galvanised brackets

I actually used smaller ones but if doing it again would mount the panel a little higher so leaves etc don't collect underneath as much and can be cleaned more easily. Another mistake was to bolt the panels to the brackets instead of screws. I can't remove them without the tedious job of removing the brackets as well.

I wasn't actually surprise by the lower wattage supplied by the Renogy considering their cost.. They are cheap panel and they seem to perform accordingly.. From 200watts of solar panel, I would say a good result would have been more around the 170watts or 85% of their capacity.. I never bought any other Renogy panel, so I can't say if this is the norm or an isolated case..

Also, regarding the Plastic mounts, mine have been going strong for 10 years now, but I agree with you. If I had to do it again, I would use the standard roof installation system. Much stronger and cheaper..

Edit:

at Brianvicki

After a quick search, I found those panel for sale at $305 per panel instead of $319.99 from the link you posted... Several sites have them for the $305 price..  HERE

Burt65 wrote:

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..... regarding the Plastic mounts, mine have been going strong for 10 years now, but I agree with you. If I had to do it again, I would use the standard roof installation system. Much stronger and cheaper..

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Perhaps 10 years ago they were quality. Here is one of the cracked and broken brackets from mine. Note the small surface area for adhesion and how much of that was broken away. I had used screws as well, but not much benefit if the mounting flange breaks away. I did break a bit more away when releasing from the adhesive but they were well and truly past it. The cracks are enough evidence of that.

Are We Lost wrote:

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Burt65 wrote:

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..... regarding the Plastic mounts, mine have been going strong for 10 years now, but I agree with you. If I had to do it again, I would use the standard roof installation system. Much stronger and cheaper..

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Perhaps 10 years ago they were quality. Here is one of the cracked and broken brackets from mine. Note the small surface area for adhesion and how much of that was broken away. I had used screws as well, but not much benefit if the mounting flange breaks away. I did break a bit more away when releasing from the adhesive but they were well and truly past it. The cracks are enough evidence of that.

 

 

-- Edited by Are We Lost on Friday 18th of July 2025 02:41:26 PM

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 Regarding the "small" surface for adhesion.. That's a lot bigger than what we use for the windows in coaches.. The biggest problem I can see there is that the plastic was not primed and therefore the silastic never actually had the chance to adhere to the plastic. You can still see the shining of the light on one side and the dirt from the weather and water on the other side of the plastic. Not sure what created those crack, but I wouldn't blame the sun for that... To my knowledge, ABS plastic does pretty well under the sun...

Like I said, I wouldn't use the ABS pieces (either the long one or the corners) anymore if I had to do the job again, but it is only for the cost involved in installing them properly, not for the reason you mentioned..

Adhesion is a separate issue. As per my previous comment I broke the bracket a little more when releasing from the adhesive. It was still mostly adhered. But I know there are better choices for adhesive. My replacement brackets are affixed with Sikaflex 11FC. I think the previous one may have been 291.

There are no shiny parts on the surfaces for adhesion. Not sure what you think you are seeing. You can see the cracks have been there some time and these were only 2+ years old.

Anyway, adhesion was not the issue. I had one bracket where the flange was still stuck down, but had cracked and separated from the rest of the mount. Once the flange separates there is only about 10% of the surface area left for holding it in place.

Anyway, I have had my say and hope others using platic mounts check them for cracks. I will leave it with this image of all 4 brackets showing the flanges broken off. The one in the previous photo is the top left .... the mount with the most surface area remaining. I think the one on the bottom right was floating free, entirely disconnected with broken flanges, or part thereof still adhered to the roof.

From the dictionary:

I can...

Last year I added an extra panel to my van roof. By chance, I found that the physical side dimensions of a suitable extra panel were within 1-2 mm of my original panel, even though the brands of the panels were different. Also the stated power of the new panel was 20 watts higher than the original panel.

So if your mounting corner brackets are in good condition and adhered well, it might be useful to check new panel dimensions before doing any removal of the mounting brackets.

My preferred method of removing such mounts is to use Dental Floss to cut through Silicon used to glue the mounts down.   Screws used in addition to Silicon complicates things.    I find a 2mm thick bead of Sika 293 does the job and the floss method for removal likes having a bit of space to work in.

Izabarack wrote:

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My preferred method of removing such mounts is to use Dental Floss to cut through Silicon used to glue the mounts down.   Screws used in addition to Silicon complicates things.    I find a 2mm thick bead of Sika 293 does the job and the floss method for removal likes having a bit of space to work in.

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We normally use piano wire to remove the windows and cut through the silastic, but I can see how Dental floss is another great alternative, especially for small areas..

Hi Brianvicki,

Whilst it is possible to join two different size panels together there can be loss of efficiency either in amps or volts depending how they are connected but then again if you have older panels they may well have degraded depending on their initial quality.  From what you have posted it looks like you are just looking at one panel but just be aware it is a 24V nominal panel in case you didn't notice.  With you having a LiFePO4 battery though I would imagine you have an MPPT controller to handle the voltage.

Firstly, whilst price is not always a reflection on quality you will find that when it comes to solar panels the cheaper ones will degrade quicker.  Keep away from the cheap Ebay and certain store outlets that cell cheaper panels.

Yes, if you are buying the Renogy you are paying a higher price than many others.  It is claimed to be more efficient in shading and that may be a consideration for you so here is a review of how it performs in certain circumstances.

https://www.youtube.com/watch?v=yMthYRR_OLg&ab_channel=DIYSolarPowerwithWillProwse 

It is not 7% smaller and 10% lighter than other 200W panels though but that shouldn't really matter to you.

I have a 200W Exotronic suitcase portable panel that has under ideal conditions produced 219W so I do all comparisons of my solar panels against that.  It has Trina cells which are one of the biggest cell manufacturers in China.  The hinges and latches on it aren't the best though but I soon fixed that issue.

I have just taken all my panels off the roof to do a rearrangement and a test on the panels as well. I don't have the figures and it is mid winter so I just do a % comparison against my portable panel, the two new Alvolta 100W panels I have just purchased had the same % output as my 200W Exotronic which was at about 85%.  They have a very sturdy frame.

The two 120W Exotronic fixed panels I have were just below in output. They seem a nice panel but the aluminum frame is very lightweight as is with the portable. They are not advertised as having Trina cells although they do look the same as the portable panel.

The 175W Victron panel was at about 80% of output and I would probably not buy another.

I have a 165W in another brand now not available in Australia and which I can't recall the name and that was at 76%.

The Renogy panels do look good and they would have been a serious contender for me in consideration of replacing my 165W and 175W panels but for their size so the Alvolta are top of my list until something else comes along.

As for removing the old brackets.  I use a wood chisel with the bevel down to cut through the excess around the outside of the bracket. You can then gauge how deep you cut. i then lift the corner of the bracket to get either fishing line or braid line under the corner with a handle tied to each end and do a sawing action.  Once the bracket is off I clean as much of the silicon off as possible with the chisel so then only a thin sliver is left. Isopropyl alcohol and hard rubbing gets rids of the rest.

I'm, with Are We Lost and would not use the plastic brackets.  I use these

https://www.solar4rvs.com.au/adjustable-black-aluminium-solar-panel-brackets

I bolt and screw the brackets on, position where I want the panels then put masking tape about 10mm out from the edges, clean and then bed them down in Sikaflex 11FC.  Then lap up over the edges with Sikaflex.  Wearing a latex glove and with a wet figure you can smooth it off but clean off excess from your finger and keep wetting it.

Good luck 

Brianvicki wrote:

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Thanks everyione for your replies very much appreciated.
I will first soend some time to hunt down panels the same size 1480 x 510, (replace both) that might be the easier option as my plastic corners are still all good , else yeah the Alvolta panels might be the go

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I had a bit of a look around and it seems that they are all 670 wide now.. Plenty of 1480, but not in 510...

I hope you find something..

Tim, what is meant by the poanel being 24v nominal.... it has confused me a bit, the panels (two of) were on the windsor seka when bought and is all 12 volt, i have renogy controller

Brianvicki wrote:

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thanks my research is coming up with the same results, bugger

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 The only other thing i can suggest is to get the new size 1480 x 670 and just relocate two of the corner. Going by your pictures, you seem to have a bit of room to move. If you take your time, they are not hard to remove without the need of breaking them...

Brianvicki wrote:

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Tim, what is meant by the poanel being 24v nominal.... it has confused me a bit, the panels (two of) were on the windsor seka when bought and is all 12 volt, i have renogy controller

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 Solar panel come in different voltages i.e. 12V and 24V but we use the term nominal voltage in relation to the system description even though the solar panels produce higher voltages than that.

You have now stated that your solar panels are 12V, but the link you provided to the Renogy solar panel is a 24V panel.  You can still it all probability use it depending on your model of solar controller as most can do multiple voltages.  I just wanted you to be aware of the panel voltage you were looking at.

Just remember when reconnecting, connect you solar controller to the batteries first (allow time for the controller to determine the battery voltage), the solar panels second and if you are using the load terminals then connect them last.

Tim

Thanks Tim for info, very much appreciated , looking at the ad, it doesnt talk about the panel being 24v, except where you see the voltage at 36v

If you notice I used the term 'nominal voltage'.

Gawd I hate using A.I. but here goes lol.

I quote, 'A solar panel's nominal voltage is a standard classification used to describe the panel's expected voltage output under specific conditions, typically used for matching panels with other system components. It's a reference point, not necessarily the exact voltage output in real-world scenarios. Common nominal voltages for solar panels are 12V, 24V, and 48V, but they can also be 18V or 20V.'

This is no different that using the term in relation to batteries which are all sorts of voltages but are still classified by their 'nominal voltage'

And yes many of us know that you can use larger voltage panels because the solar controllers regulate the voltage to what ever the system designed and set to.  People still do have solar controllers that cannot take the higher voltages and that is why I asked Brian about his controller and I did state it is possible to use the panel he selected.

Why did I mention it was a 24V panel?  Because if he had bought it and not realized and and then wanted to add to an existing panel or add another panel later which was a 12V 'nominal panel' then he would run into problems.

Brianvicki wrote:

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Thanks Tim for info, very much appreciated , looking at the ad, it doesnt talk about the panel being 24v, except where you see the voltage at 36v

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 Yes Brian and that is why I brought it to your attention. Some are categorised as 12V and 24V and others are not.

TimTim wrote:

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If you notice I used the term 'nominal voltage'.

Gawd I hate using A.I. but here goes lol.

I quote, 'A solar panel's nominal voltage is a standard classification used to describe the panel's expected voltage output under specific conditions, typically used for matching panels with other system components. It's a reference point, not necessarily the exact voltage output in real-world scenarios. Common nominal voltages for solar panels are 12V, 24V, and 48V, but they can also be 18V or 20V.'

This is no different that using the term in relation to batteries which are all sorts of voltages but are still classified by their 'nominal voltage'

And yes many of us know that you can use larger voltage panels because the solar controllers regulate the voltage to what ever the system designed and set to.  People still do have solar controllers that cannot take the higher voltages and that is why I asked Brian about his controller and I did state it is possible to use the panel he selected.

Why did I mention it was a 24V panel?  Because if he had bought it and not realized and and then wanted to add to an existing panel or add another panel later which was a 12V 'nominal panel' then he would run into problems.

 

 

-- Edited by TimTim on Monday 21st of July 2025 02:31:17 PM

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I'm sure you are trying to help people here, but it seems that you are creating more confusion than anything else..

I'm sure that Brianvicki is not stupid. He can clearly see that it is a 36 volts panel. NOT sure why you are saying that it is a 24 Volts. Common solar panel voltage is not as you mentioned 12-24-48 Volts. Those are the most common batteries bank voltage! Two completely different things! That's why you are confusing people. Perhaps you should only have an opinion when you are properly informed on the subject.

It is very common for professional installation to try to use the highest voltage solar panel you can fit, simply because it cuts down in wire size and circuit breaker, beside allowing the MTTP to try to give you the best wattage, no matter what the conditions are.. My panels are 64Volts to give you an idea, and they are powering a 24Volts battery bank..

This is another post where you are giving the wrong advice, as the truth is exactly the opposite of your statement, and frankly I'm not sure of why you are doing it...

Have a look:  Polycrystalline vs Monocrystalline solar panels

It is a great thing to try to help, but if the advice given is wrong, then you are doing more damage than simply not posting anything..

Oh I have a stalker....

If you notice I used the term 'nominal voltage'.

Gawd I hate using A.I. but here goes lol.

I quote, 'A solar panel's nominal voltage is a standard classification used to describe the panel's expected voltage output under specific conditions, typically used for matching panels with other system components. It's a reference point, not necessarily the exact voltage output in real-world scenarios. Common nominal voltages for solar panels are 12V, 24V, and 48V, but they can also be 18V or 20V.'

I will get to reply to your other posts when I have time 

-

TimTim wrote:

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Oh I have a stalker....

If you notice I used the term 'nominal voltage'.

Gawd I hate using A.I. but here goes lol.

I quote, 'A solar panel's nominal voltage is a standard classification used to describe the panel's expected voltage output under specific conditions, typically used for matching panels with other system components. It's a reference point, not necessarily the exact voltage output in real-world scenarios. Common nominal voltages for solar panels are 12V, 24V, and 48V, but they can also be 18V or 20V.'

  

I will get to reply to your other posts when I have time 

-- Edited by TimTim on Tuesday 22nd of July 2025 02:09:44 PM

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Every forum has one...   

It's ok Tim.. You are the best, and we are all stupid people here and can't read between the lines...  

Thanks to everyone for their ideas, i certainly learnt a lot about the brackets, removal of, and different other brackets.

also my research taught me about shingle panels, which I hadnt heard of.

so , in the end the answer to my problem, was far simpler and less costly.

$2.80 , an hour of research and about an hour at most to implement, and 45 minutes of travel.

after testing the panel for voltage which was good, I removed the two diodes, replaced them from altronics, and bingo, panel is working

and fitted back in its existing brackets