Is Sunpower price difference worth it? -- thoughts, posting as new topic

[Mike90250]

That copper heat sink is useless unless there are fins on it. otherwise, it's a heat spreader, and only insures all parts are the same temperature. SP has lots of marketing hype.

[littleharbor]

Maybe Sunpower cells should have fins.
Sunpower brown cells 2 (2).jpgSunpower brown cells (2).jpg

[LLB]

That copper heat sink is useless unless there are fins on it. otherwise, it's a heat spreader, and only insures all parts are the same temperature. SP has lots of marketing hype.

Wow I was about to let this go as well, to each his own, but you guys are just relentless. Please post more pictures of 1970 panels on abandoned houses. If you can get the data from that SP system and a LG or Panasonic near by this house, I'd like to compare.

My understanding from the SP brochures is the copper makes for a more resilient cell, that's all. I can't find any sales literature mentioning it being a heat sink. Seems most panels fail do to corrosion and tab failure and from the research literature I can find from LG, Panasonic (which I find very lacking) SP has really focused on those issues better than everyone else - see attached report.

Well , that's about all for me. I'm sure I'll go down in a ball of flames in about an hour. Had other questions but I guess I'll have to settle for being a lurker here. Just trying to say you old dogs are greatly appreciated and knowledge valuable but things do change. After reading that report (and some was conducted by 3rd parties and some by SP themselves - see conclusion/Summary and final 4pgs. of references) I got a hold new respect for SP and think the cell technology they've achieved is worth a few more cents per watt.

[LLB]

I went to Google Images searching for "burnt solar panels" and found these. Funny scrolling for pages I couldn't find any SP.

[J.P.M.]

Wow I was about to let this go as well, to each his own, but you guys are just relentless. Please post more pictures of 1970 panels on abandoned houses. If you can get the data from that SP system and a LG or Panasonic near by this house, I'd like to compare.

My understanding from the SP brochures is the copper makes for a more resilient cell, that's all. I can't find any sales literature mentioning it being a heat sink. Seems most panels fail do to corrosion and tab failure and from the research literature I can find from LG, Panasonic (which I find very lacking) SP has really focused on those issues better than everyone else - see attached report.

Well , that's about all for me. I'm sure I'll go down in a ball of flames in about an hour. Had other questions but I guess I'll have to settle for being a lurker here. Just trying to say you old dogs are greatly appreciated and knowledge valuable but things do change. After reading that report (and some was conducted by 3rd parties and some by SP themselves - see conclusion/Summary and final 4pgs. of references) I got a hold new respect for SP and think the cell technology they've achieved is worth a few more cents per watt.

I'd respectfully suggest you consider that not everything you read is unbiased or just maybe not meant in your best interests. Most of the Sunpower white paper and other such hype falls under that category.

Point behind a lot of these caveats is that Sunpower stuff is a lot of hype, considered by more than a few in the know to be disingenuous and biased in ways that seem be and meant to separate the solar ignorant from their assets. FWIW, I've seen such ignorance time and again, upfront and personal from neighbors and friends for years.

If you consider those statements to be flaming in nature, so be it. This is, among other things a place for opinions, and opinions vary.

Take what you want of the above. Scrap the rest.

[LLB]

I'd respectfully suggest you consider that not everything you read is unbiased or just maybe not meant in your best interests. Most of the Sunpower white paper and other such hype falls under that category.

Point behind a lot of these caveats is that Sunpower stuff is a lot of hype, considered by more than a few in the know to be disingenuous and biased in ways that seem be and meant to separate the solar ignorant from their assets. FWIW, I've seen such ignorance time and again, upfront and personal from neighbors and friends for years.

If you consider those statements to be flaming in nature, so be it. This is, among other things a place for opinions, and opinions vary.

Take what you want of the above. Scrap the rest.

Who could consider those comments flaming. It was one of your milder replies. I am somehow oddly honored. It did not go unnoticed that you commented a few days ago something to the effect (it maybe that SP is not trying to charge 20% premium all the time and is trending down) I'll take that, little steps are good. I think forums and review sites that help people compare prices brings transparency and has a leveling effect.

I just wish I could find a LG or Pana white paper that went to as much trouble as SP. Sure SP used their best numbers and the competitions worst, but that's what everyone does (and some was very straight up 3rd party) . It's up to us to read between the lines, even though we shouldn't have to. If LG and Pana aren't going to defend themselves than so be it.

[Mike90250]

Wow I was about to let this go as well, to each his own, but you guys are just relentless. Please post more pictures of 1970 panels on abandoned houses. If you can get the data from that SP system and a LG or Panasonic near by this house, I'd like to compare.

My understanding from the SP brochures is the copper makes for a more resilient cell, that's all. I can't find any sales literature mentioning it being a heat sink. Seems most panels fail do to corrosion and tab failure and from the research literature I can find from LG, Panasonic (which I find very lacking) SP has really focused on those issues better than everyone else - see attached report.

Well , that's about all for me. I'm sure I'll go down in a ball of flames in about an hour. Had other questions but I guess I'll have to settle for being a lurker here. Just trying to say you old dogs are greatly appreciated and knowledge valuable but things do change. After reading that report (and some was conducted by 3rd parties and some by SP themselves - see conclusion/Summary and final 4pgs. of references) I got a hold new respect for SP and think the cell technology they've achieved is worth a few more cents per watt.

First, if you are quoting me about copper heat spreaders, and refer to a photo I did not post, it poor reflection on you.
Copper is flexible. As is aluminum, silver and gold

Silicon wafers are not. Gluing silicon wafer to something flexible, does not make Silicon flexible, it simply keeps the pieces together like a broken car windshield laminate. The ads don't show how many tests were done that failed the flex demo before they got one to work.


Coefficients of Linear Thermal Expansion
Silicon 3 - 5
Silver 19 - 19.7
Glass, plate 9.0
Gold 14.2
Copper 16 - 16.7
Aluminum 21 - 24 ( from https://www.engineeringtoolbox.com/l...ents-d_95.html )

Because microcracking takes years to show up, things will work fine for a while. Maybe SP uses some compliant interface between the copper and Si. But it's showmanship

[littleharbor]

[QUOTE=LLB;n377227]

Wow I was about to let this go as well, to each his own, but you guys are just relentless. Please post more pictures of 1970 panels on abandoned houses.



In case you haven't noticed, these are Sunpower panels. Not sure how you figured these are 70's era panels on abandoned buildings. I personally have a couple of the same failed panels in my possession that were mfg. in this millennium. Yes their cells can get hot.

[Kingram]

I went to Google Images searching for "burnt solar panels" and found these. Funny scrolling for pages I could find any SP.

Wow that is some scary pictures ,Here is another.

http://www.breitbart.com/london/2015...ove-town-hall/

[Sunking]

Those small fires are nothing compared to Dietz & Watson factory solar panel fire. All fire fighters could do is sit and watch a 300,000 ft/2 burn to the ground. Good news is they had one heck of a BBQ when the fire burned itself out.

[LLB]

First, if you are quoting me about copper heat spreaders, and refer to a photo I did not post, it poor reflection on you.
Copper is flexible. As is aluminum, silver and gold

Silicon wafers are not. Gluing silicon wafer to something flexible, does not make Silicon flexible, it simply keeps the pieces together like a broken car windshield laminate. The ads don't show how many tests were done that failed the flex demo before they got one to work.


Coefficients of Linear Thermal Expansion
Silicon 3 - 5
Silver 19 - 19.7
Glass, plate 9.0
Gold 14.2
Copper 16 - 16.7
Aluminum 21 - 24 ( from https://www.engineeringtoolbox.com/l...ents-d_95.html )

Because microcracking takes years to show up, things will work fine for a while. Maybe SP uses some compliant interface between the copper and Si. But it's showmanship

Mike the copper comments started I believe a few pages before your comment, regardless irrelevant. What are you saying, I can't refer to two comments I read in a thread, especially when I didn't put any names to them, oh OK. Actually I believe I said "you guys" so maybe don't take it personally you are in good company!

To your other point (the windshield argument) of gluing copper to silicon doesn't make silicon flexible". True and not, because I think we both understand this is a microscopic situation. I would much rather have the new windshield tech then the old. Most of the time they keep making power other panels can't go on.

Here I want to address the constant strawman technique used to constantly bash SP. The OP said he saw a .70/watt premium and was OK with it. He mentioned other benefits like efficiency , shading, quality of build and warranty. And everyone jumped on the warranty and dismissed everything else with "efficiency is a muted point there are others that do just as good".

Agreed all warranties are a bitch to file a claim against because they make the rules and give themselves ever out.

In rereading mine, even though I bought it, I can't touch it in a any way. Only "licensed" and "certified" SP techs or SP dealer techs. So technically I can't even say I took a reading with my meter and I think there is something wrong, please check it out. All claims have to originate from a software reading. Nice little package they have created.

I'm trying to say I see a high quality build and higher quality materials. Since I attached the white paper earlier I'll refer to it.

The design does not look very different to the casual observer

What the heck! mod
You cut 50% of my post!!
If this board doesn't allow you to quote something then say so and leave the rest of my words. Don't just cut everything below it!

Well everyone you'll have to believe it was a good post.
It covered Mikes thermal expansion and how SP only receives 25% more performance but it cost them 33% more. (base metal price of copper $3, alum $1)
It had a NASA space analogy paragraph in there about them using premium materials and tech.
And basically wrapped it all up by saying they are reaching their high efficiency somehow. I say it is by using high quality materials. Its not like they are under-performers and charging a 20% premium. Anyone care to say how you think they are achieving the highest marks in the industry, using the same stuff as everyone else?
Then drove it home with saying the original poster said he thought SP was worth the ~.70/watt premium and I agree.
I just disagree emphatically to reduce the argument to a "commodity item", because they are putting in high quality commodities and better tech and the high quality commodities alone demand premium pricing. I don't think anyone would argue that there are different grades of aluminum or copper. While I can't prove what grade they use, neither can you prove they don't. At least I can say if every company is using the same grade/quality of components then why aren't they achieving the same life spans of efficiencies. Efficiency is nothing without build quality.

We all should really go back and read # 1 and 7 on page 1, they said all this already much better than I.

Just in case this deletion of half my post was a computer glitch I'm going to retry to add the text that belongs under "The design does not look very different to the casual observer"
The design does not look very different to the casual observer
Nope looks like the mods don't allow quoting other works, most be a copywrite issue, so i'll put it in my own words... but you can read it on page 12.

Both have cells encapsulated in a polymer that is bonded to the front and back. Materials and their quality can very widely and their specific properties can have important impacts on performance. Materials and suppliers for other laminate components, such as glass, encapsulant and backsheet, vary between manufacturers and these properties have ramification on long-term reliability.

And to those that say don't believe everything you read. I would hate to live in that world. (It might throw a wrinkle in religion-for heavens sake) The devil is always in the details and we don't have them, so in my book you can't through the baby out with the bath water.

[LLB]

[QUOTE=littleharbor;n377251]

Wow I was about to let this go as well, to each his own, but you guys are just relentless. Please post more pictures of 1970 panels on abandoned houses.



In case you haven't noticed, these are Sunpower panels. Not sure how you figured these are 70's era panels on abandoned buildings. I personally have a couple of the same failed panels in my possession that were mfg. in this millennium. Yes their cells can get hot.

Of course I noticed, they're the only company that cuts 5% of their surface area (corners) and still out performs everyone.
70's area? Oh I don't know, looked like an old roof and you were leading everyone to think they were new by not clarifying their age, so why not.

"Yes their cells can get hot". Are you trying to infer SP cells get hot and others don't? I don't think anyone has been saying SP cells have a heating problem.

You have the panels! Great! What's the story behind them? Were they in Saudi Arabia? On a poorly designed system? Abused in some way?

[littleharbor]

You're revealing your ignorance here. The 5% clipped corners, as you call them are indicative of monocrystalline cell manufacture. Half of all solar panels sold are monocrystalline. Fact is the corners aren't clipped at all. the cells are made from round ingots which have the sides squared off to be able to fit tighter together in the module. That's why the clipped corners as you call them are slightly curved.

The panels were removed from a roof in costal Southern California. because of this failure. BTW Mr. Fanboy, do you know that Sunpower systems are only installed by authorized Sunpower agents so any design flaw would be on Sunpower dealers. No, they weren't abused, sometimes chit happens and even your precious Sunpower panels can have problems.

Monocrystalline cells.jpg

[bcroe]

Hmm, I wonder if those cut corners amount to 5%? Need some dimensions to do the
calculations. Bruce Roe

[LLB]

You're revealing your ignorance here. The 5% clipped corners, as you call them are indicative of monocrystalline cell manufacture. Half of all solar panels sold are monocrystalline. Fact is the corners aren't clipped at all. the cells are made from round ingots which have the sides squared off to be able to fit tighter together in the module. that's why the clipped corners as you call them are slightly curved.

The panels were removed from a roof in costal Southern California. because of this failure. BTW Mr. Fanboy, do you know that Sunpower systems are only installed by authorized Sunpower agents so any design flaw would be on Sunpower dealers. N, they weren't abused, sometimes chit happens and even your precious Sunpower panels have problems.

Monocrystalline cells.jpg

Thank you Bruce, at least someone got it.

littlenarbor - see the beginning of post #73 from inetdog.

They are obviously not 5%, but the strawman m.o. just won't die. Can't someone have a differing opinion and prefer another brand without being called a fanboy.

Did it occur to you that if I've seen my share of SP cells the missing stripes down the front of the cell might be the first thing I notice. Not to mention you put SUNPOWER across the top. Not my ignorance showing.

Wow, "coastal" California did that? No design flaw or anything out of the ordinary? That wasn't really much of a story, no more details? Surely you would like to explain where the weakness in the SP panel is?
The failure rate of panels is 5 in 10,000.
https://www.nrel.gov/news/program/20...gradation.html
Never said SP didn't have problems (yet more strawmaning) just saying they are worth a reasonable premium.

Bruce, I apologize in advance for the above. I don't want any association with me to accidentally infect you via strawmanits.