Vehicle mounted solar panels

[Spacemanspiff]

Hello,
I built out will's 400 watt system about 2.5 years ago. Everything has worked out great until recently when I noticed my four 100 watt panels are only producing about .4 KW in a good day of sun. I climbed up on top of the van and all four of my panels had these weird spider web looking reddish brownish marks underneath the glass. It almost looks like rust. I bought them from Rich solar on Amazon and have tried contacting them both through Amazon and their websites customer support for about 2 weeks with no response. I'm wondering if anybody here has seen anything like this before? How does something like this happen? Are my panels shot? Is something like this a warranty issue? Is this something that could have been caused by the vibration of my van driving around? Any answers would be super helpful. Thanks in advance for anyone who chooses to respond.

 

[12VoltInstalls]

Bought from amazonian?

 

[rmaddy]

Do you mean 0.4kWh in a day? 0.4kW is 400W. You'd be lucky to get the full 400W from your 400W panels even in the summer.

I have 990W of panels on my trailer. Yesterday I got 0.96kWh of solar but due to where I'm parked I'm shaded out by about 12:00pm so I'm only getting half of what I could be. My panels are in series so I get some useful power even in low sun.

If you were at about the same latitude (almost 41ºN) but with no shading issues then you might get at most 0.8kWh in a day right now. Do you have any shading issues? How are your panels arranged? What is the panel Voc? What is your system voltage?

 

[12VoltInstalls]

Do you mean 0.4kWh in a day?

That’s how I took it.
Assumed good exposure, too
Maybe a wrong assumption.

 

[Spacemanspiff]

Yes 0.4 in a day. I used to easily get a whole kWh in a day easy. Obviously less in the winter. Unless I have completely misunderstood things. One 100 watt panel should produce 100 Watts of power in an hour in optimal conditions (correct angle, good sunlight, no shade etc) correct? That being said with four I should have 400 watts in an hour under optimal conditions. I guess my main concern is my monitor on my charge controller used to say I was getting about 200 Watts around this time of year. Now I'm lucky if I get 40. This is around 12:00 with no shading issues.

 

[Spacemanspiff]

Ohh, I also just realized I never uploaded the picture I took.

 

[Spacemanspiff]

Whoops. Here's the picture.

 

[rmaddy]

A 100W panel will produce 100Wh in an hour, under ideal conditions. Your panels are mounted flat, in winter. You will never get close to that.

You said you used to see 200W in the winter but now you only see 40W. That can't be right because earlier you said you produced 400Wh in day. It would take 10 hours at 40W to produce 400Wh and there is no way, this time of year in the northern hemisphere, to get 10 hours of sun. Producing 400Wh in a day with 2 hours of sun would mean your panels are putting out up to 200W midday. That's actually very good for flat mounted panels this time of year.

 

[Spacemanspiff]

You said you used to see 200W in the winter but now you only see 40W. That can't be right because earlier you said you produced 400Wh in day.

Yeah, I see your point. I just know that I looked at my monitor several times and noted that I was generating around 40 watts around peak sun time and I generally get more than that. At the end of that day it said I generated .4 kw. I'm definitely not generating what I used to. I'll have to do some more research and unmount the panels and point the directly into the sun and hook up a volt meter. Right now my battery died overnight so I need to jump it and on a better day (in the middle of a cloudy windstorm right now) test it out. Did you see the picture I uploaded? I'm curious your thoughts on that.

 

[rmaddy]

I did see the picture. I don’t have any experience with what it shows. It is a strange pattern.

 

[Solar Guy Richard]

Have you tested the output of each panel individually to see if they are all producing the same or if there is an outlier?

 

[Cajunwolf]

Have you tested the output of each panel individually to see if they are all producing the same or if there is an outlier?

LoL, you beat me to it.

 

[ianganderton]

That panel doesn’t look good. Are the 4 connected in series or parallel? Is it all 4 panels affected like this or just that one

Not sure just testing them with a volt meter and no load gives good results. You will need a load to see output. It’s watts that count not volts

I would try testing each panel by connecting them separately to your SCC & battery. Your monitor will probably tell you how many volts, amps and therefore watts they are each putting out

 

[ianganderton]

This looks similar damage



From here https://www.winaico.com/blog/common-solar-panel-defects/

SNAIL TRAILS CAN BE SIGNS OF MICROCRACKS​

When the underlying solar cells are broken, cells can continue to generate electric current along the cracks, causing localised heat that breakdown the cell surface and EVA.

If water vapour is also present, discoloured snail trails are formed along the microcracks to not only reduce energy production but also compromise appearance.

 

[ianganderton]

This page has a different description on how snail trail type damage can happen

The Five Most Common Problems with Solar Panels

Problems with solar panels can result in a production loss of up to 20%. We have listed the five most common problems with panels for you.

greendealflow.com

 

[WinnieView1]

Is there an airgap beneath the panels?

 

[McCarthy]

Bad build quality made in China, so water creeped in and started corrosion which increases internal resistance in (solar) cells as well as blocking some light.

Most solar panels on Amazon are being sold by sellers sitting in China. They use US based fulfillment centers. Customer services is usually China based and they tend to ignore warranty claims because they can't repair anything and any warranty claim is a full loss for them.

- Don't buy solar panels made in China. Amazon is loaded with this junk!

- Buy commercial grade US or Canadian made panels from a local dealer. They are also rated for high winds stemming from weather and storms. This will be handy when driving on the highways and facing rain.

Instead of installing 4 crappy China made 100 watt panels, get 1 large 400 watt US made and commercial grade panel. I got my 465 watt panel for 220 bucks locally.

If you have fans in the roof of your RV or van, try to replace them with low profile versions and build a rack for the solar panel to go on-top. Or install side wall mounted fans. Roof top AC's can be exchanged with much better split systems.

 

[Spacemanspiff]

Have you tested the output of each panel individually to see if they are all producing the same or if there is an outlier?

Not yet. I'm visiting family for the holiday tomorrow. And when I come back I will have to go into an 8-day shift of work. So it'll be a bit before I can test them.

That panel doesn’t look good. Are the 4 connected in series or parallel? Is it all 4 panels affected like this or just that one

Not sure just testing them with a volt meter and no load gives good results. You will need a load to see output. It’s watts that count not volts

I would try testing each panel by connecting them separately to your SCC & battery. Your monitor will probably tell you how many volts, amps and therefore watts they are each putting out

Yes all four are like that. Yeah that's a good idea I'll try that when I have time.

Is there an airgap beneath the panels?

Yep!

Bad build quality made in China, so water creeped in and started corrosion which increases internal resistance in (solar) cells as well as blocking some light.

Most solar panels on Amazon are being sold by sellers sitting in China. They use US based fulfillment centers. Customer services is usually China based and they tend to ignore warranty claims because they can't repair anything and any warranty claim is a full loss for them.

- Don't buy solar panels made in China. Amazon is loaded with this junk!

- Buy commercial grade US or Canadian made panels from a local dealer. They are also rated for high winds stemming from weather and storms. This will be handy when driving on the highways and facing rain.

Instead of installing 4 crappy China made 100 watt panels, get 1 large 400 watt US made and commercial grade panel. I got my 465 watt panel for 220 bucks locally.

If you have fans in the roof of your RV or van, try to replace them with low profile versions and build a rack for the solar panel to go on-top. Or install side wall mounted fans. Roof top AC's can be exchanged with much better split systems.

It's my understanding that rich solar is a Canadian company? But maybe they're just made in China? Do you have a brand that you suggest?

Thanks everybody for all the responses.

 

[Cajunwolf]

Bad build quality made in China, so water creeped in and started corrosion which increases internal resistance in (solar) cells as well as blocking some light.

Most solar panels on Amazon are being sold by sellers sitting in China. They use US based fulfillment centers. Customer services is usually China based and they tend to ignore warranty claims because they can't repair anything and any warranty claim is a full loss for them.

- Don't buy solar panels made in China. Amazon is loaded with this junk!

- Buy commercial grade US or Canadian made panels from a local dealer. They are also rated for high winds stemming from weather and storms. This will be handy when driving on the highways and facing rain.

Instead of installing 4 crappy China made 100 watt panels, get 1 large 400 watt US made and commercial grade panel. I got my 465 watt panel for 220 bucks locally.

If you have fans in the roof of your RV or van, try to replace them with low profile versions and build a rack for the solar panel to go on-top. Or install side wall mounted fans. Roof top AC's can be exchanged with much better split systems.

American, as well as Canadian and European manufacturers, are having issues with micro-cracks, defects, and snail trials too. There are many good-quality manufacturers in China, and there are millions of crappy ones too. The panels in question here, the author's panels are... not of the best quality to be nice.

 

[Cajunwolf]

A friend of mine in Oklahoma bought some of the used panels Will tested sometime back. He purchased some 24-volt panels with snail trails for $38 each, a pallet load. That was near a year ago, and I talked to him back in May when he got everything set up and running. He said the panels were working great and was about to buy more. I haven't heard from him since. I've tried a couple of times, but he apparently has a new number. That's what his mother-in-law says; that sounds suspicious.