Why not CIGS?

[Marine359]

I love CIGS!
They perform way better than mono in real world camping situations. See my other post. I tested CIGS against mono. The panels cost more, but the array actually costs less than hard mono panels, when you add the cost of mounting hardware, plus paying somebody to install them. Then just wait for the leaks to start. I installed 3 CIGS panels in about 35 minutes DIY. No hardware, no holes in roof, and I can walk on them. In my mid-seventies, I wasn’t gonna get on my RV roof for hours struggling to install heavy mono panels, and hoping I wouldn’t cause a leak or have a hard panel come off and kill somebody. And I’ll certify that a 100w CIGS will produce more watts in a day than a 100w hard mono panel In real worl camping use. Especially in rain, clouds, or partial shade, the CIGS blows mono out of the water. You can trust Will Prowse. He’s good, but everything is under controlled lab like conditions. I don’t think he’s ever been boondocking in his life. CIGS wins on most fronts. I’m not affiliated with any product manufacturer. And my CIGS don’t seem any more affected by bird poop or dirt than mono panels. Don’t know where that myth comes from. They’re certainly easier to clean. Did I mention that you can walk on them, so hose and mop before a trip and you’re good to go. There’s something else you haven’t considered when comparing CIGS to mono. Efficiency numbers don’t mean diddly on their own. The CIGS panel produces more watts in a day than a same wattage mono because it’s Voc is almost double the Voc of a mono panel. The CIGS keep mppt controllers at or near maximum power point a higher percentage than mono due to its higher voltage. In real world use on an RV CIGS outperforms mono.

 

[SilverbackMP]

You can trust Will Prowse. He’s good, but everything is under controlled lab like conditions. I don’t think he’s ever been boondocking in his life.

Fairly certain he was living in a van down by the river at one point and that’s how he got his start in solar.

 

[curiouscarbon]

No hardware, no holes in roof, and I can walk on them. In my mid-seventies, I wasn’t gonna get on my RV roof for hours struggling to install heavy mono panels, and hoping I wouldn’t cause a leak or have a hard panel come off and kill somebody

Very happy to hear of this! Reduces risk to humans, both from maintenance and operating at speed

The shading aspect and overall balance with watts per square area vs power production loss is interesting.

May I ask, are you doing anything about the edges of the panels? Some people have had issues with water intrusion leading to encapsulation failure. Some manufacturers seem to suggest some sort of weather resistant tape to reduce water issues. Mine failed pretty quickly in the elements.

Kind regards

 

[cs1234]

For the added cost, CIGS should at least be able to be kept outdoors without having to tape their edges.

 

[asot550]

I love CIGS!
They perform way better than mono in real world camping situations. See my other post. I tested CIGS against mono. The panels cost more, but the array actually costs less than hard mono panels, when you add the cost of mounting hardware, plus paying somebody to install them. Then just wait for the leaks to start. I installed 3 CIGS panels in about 35 minutes DIY. No hardware, no holes in roof, and I can walk on them. In my mid-seventies, I wasn’t gonna get on my RV roof for hours struggling to install heavy mono panels, and hoping I wouldn’t cause a leak or have a hard panel come off and kill somebody. And I’ll certify that a 100w CIGS will produce more watts in a day than a 100w hard mono panel In real worl camping use. Especially in rain, clouds, or partial shade, the CIGS blows mono out of the water. You can trust Will Prowse. He’s good, but everything is under controlled lab like conditions. I don’t think he’s ever been boondocking in his life. CIGS wins on most fronts. I’m not affiliated with any product manufacturer. And my CIGS don’t seem any more affected by bird poop or dirt than mono panels. Don’t know where that myth comes from. They’re certainly easier to clean. Did I mention that you can walk on them, so hose and mop before a trip and you’re good to go. There’s something else you haven’t considered when comparing CIGS to mono. Efficiency numbers don’t mean diddly on their own. The CIGS panel produces more watts in a day than a same wattage mono because it’s Voc is almost double the Voc of a mono panel. The CIGS keep mppt controllers at or near maximum power point a higher percentage than mono due to its higher voltage. In real world use on an RV CIGS outperforms mono.

Thanks for sharing your experience!

I took a look at your other post and you mention ~20% greater gains over a day from a CIGS panel when compared to a same wattage mono panel. I think that tracks roughly in line with my shaded performance estimates.

I think that still points to half-cut rigid panels outperforming when you're limited on space like in mobile applications. Rough math... the same area of CIGS panels will only be ~70% of the full wattage of a rigid panel (ie: you can only fit 70w of CIGS in the space of a 100w rigid panel, or alternatively you can fit ~140w of rigid panels in the space of a 100w CIGS. That means that even though the CIGS is outperforming by 20% over the course of the day, you're still only getting ~85% of the power out of the same area compared to the rigid.

There are other benefits of CIGS like you mention... walkable, easy to install, lighter weight, lower profile (better for aerodynamics and fuel efficiency) as well as being able to conform to curved surfaces like on a teardrop. For nominally flat roofs though, as long as you're capable of DIYing your own install I think the rigids are the way to go from a price and performance perspective.

 

[Marine359]

You’re probably right that hard mono has the advantage if you’re doing a DIY install. But there’s so much risk in putting holes in your roof unless you REALLY know what you’re doing. I would never buy a used RV with a DIY hard mono install. There are tech shops that you have to pay some heady bucks to, but you’ll have total confidence in the install. This was a huge motivating factor in my choosing CIGS. My install was in January of this year. i check the panel before every RV use. So far there is no sign of edge deformations , or delamination. If I see any edge deformation, I’ll just get up there and put on some velabond tape. No biggie. Looking at pictures of Rich Solar CIGS vrs BougeRV CIGS. it appears the BougeRv panels are better constructed. As far as Will Prowse, he does do all of his reviews in controlled environment and makes no mention of how products might perform differently in real world RVing.

Mine look like this:

 

[asot550]

Fwiw, there are plenty of ways to mount rigid panels without drilling through your roof. Will covers a corner bracket method here:

Panels mounted to racks that don't require holes through the roof are also plenty secure.

 

[Marine359]

Fwiw, there are plenty of ways to mount rigid panels without drilling through your roof. Will covers a corner bracket method here:

Panels mounted to racks that don't require holes through the roof are also plenty secure.

The glue down corner mounts might work well on a fiberglass roof, but I definitely wouldn’t trust them a rubber type roof any more than rails with VHB tape. When air gets under the panel while driving, there will be uplift force. That force can rip the rubber sheath off the substrate. Most travel trailers have rubber roofs. The only safe mounting of hard panels on rubber roof involves holes thru the roof. Here’s what can happen with corner mounts:

 

[cs1234]

The glue down corner mounts might work well on a fiberglass roof, but I definitely wouldn’t trust them a rubber type roof any more than rails with VHB tape. When air gets under the panel while driving, there will be uplift force. That force can rip the rubber sheath off the substrate. Most travel trailers have rubber roofs. The only safe mounting of hard panels on rubber roof involves holes thru the roof. Here’s what can happen with corner mounts:

Guess that's why at the end of the video, Will has this disclaimer..

 

[curiouscarbon]

proper selection of safety line is important, and that disclaimer is great!

adhesive + proper safety line seems workable to me, but really really important to ensure the line will be ready to take the brunt of the tug of the wind sail if things get flappy, especially after sitting in the sun for many hours. the mounting point for said safety line also benefits from robustness.

 

[asot550]

The glue down corner mounts might work well on a fiberglass roof, but I definitely wouldn’t trust them a rubber type roof any more than rails with VHB tape. When air gets under the panel while driving, there will be uplift force. That force can rip the rubber sheath off the substrate. Most travel trailers have rubber roofs. The only safe mounting of hard panels on rubber roof involves holes thru the roof. Here’s what can happen with corner mounts:

Proper installation is key for any method. I agree that CIGS/flexible solar panels are both more tolerant to improper installation AND due to their lighter weight a smaller risk to others in a total failure.

However, in the video shared we can determine that the issue was not the corner mounts to the RV, but rather the solar panel to the corner mount. You can see in the thumbnail that there is one corner mount missing from the panel. Reviewing the footage in slow motion shows that the missing corner mount was on the leading edge of the panel, and not dislodged after the panel left the roof (thus the corner mount is still attached to the roof).

What happened is the bolts from that corner either failed or rattled loose, allowing that corner of the panel to detach from its corner mount. After that panel corner detaches, wind is able to lift the corner and torques the other leading edge from the roof. Once both leading edge corners fail the panel easily rips the trailing edge corners.

 

[eXodus]

proper selection of safety line is important, and that disclaimer is great!

adhesive + proper safety line seems workable to me, but really really important to ensure the line will be ready to take the brunt of the tug of the wind sail if things get flappy, especially after sitting in the sun for many hours. the mounting point for said safety line also benefits from robustness.

I've riveted two safety uplift brackets per panel into the metal trusses of the roof.
But not as as loose rope - don't think that would do any good. A rope/wire would just rip out of the panel. The aluminum is not very strong.