SolarCity Isn't Looking So Terrible

[max2k]

...
Further the SolarEdge inverter shouldn't generally (other than commercial installs) be placed ON the roof.

and what about its optimizers? I wish I could share your optimism. Granted, SMD PCBs improved odds a lot compare to 'through hole' technology as it was impossible to guarantee consistency there. So nowadays I'd expect reliability would be defined by quality of the components used, connector's plating and probably the way heavier components attached to PCB: more than once I saw such components developing hair line cracks in the solder after just few years in use. It seemed their mass, temperature and vibration from power conversion were contributing factors. Better manuf used special short 'tubes' in each hole flattened on both sides of the hole and soldered inductor/transformer legs inside those 'tubes'. That surprisingly worked much better and easily extended MTBF may be x10 times. Basically it was non issue for those. Big capacitors attached to PCB was the same story- manuf who glued them with thermo glue had them running forever, ones who skipped the glue had hair cracks within few years. As you see it is theoretically possible to get prob to 10 years by making specific efforts. Hopefully major manuf of the modern inverters have good grasp of these 'tricks'.

[ButchDeal]

and what about its optimizers? I wish I could share your optimism.

You specifically said the inverter had a life time of 8-10 years and mentioned the optimizers separately.
SolarEdge has all silicon only in the optimizers no electrolytic capacitors at all. The part count is very low as well and they have an oversized heat sink.

We have had very few failures of optimizers with the majority being damaged by external forces usually critters.

[bcroe]

We have had very few failures of optimizers with the majority
being damaged by external forces usually critters.

I wonder if an argument could be made, that a ground mount may have fewer failures
due to critters? I have zero equipment failures; things like squirrels can't nest in them.
Bruce Roe

[max2k]

You specifically said the inverter had a life time of 8-10 years and mentioned the optimizers separately.
SolarEdge has all silicon only in the optimizers no electrolytic capacitors at all. The part count is very low as well and they have an oversized heat sink.

We have had very few failures of optimizers with the majority being damaged by external forces usually critters.

but you understood the context, right? Following your logic microinverter based system has absolute reliability as there's no central inverter to fail .

I was considering their reliability from the owner point of view- how much maintenance headache it might create in the future and how distant that future is.

Do you happen to have link/image of the optimizer's and or inverter internals? While I can understand why there might be no electrolytic caps in there they'd still need inductors. Given power level involved and modern elements that could probably be done using SMD components but still interesting to see.

[ButchDeal]

I wonder if an argument could be made, that a ground mount may have fewer failures
due to critters? I have zero equipment failures; things like squirrels can't nest in them.
Bruce Roe

Deer and goats are pretty unlikely to climb on your roof on the roof mount side.

[ButchDeal]

but you understood the context, right? Following your logic microinverter based system has absolute reliability as there's no central inverter to fail .

I was considering their reliability from the owner point of view- how much maintenance headache it might create in the future and how distant that future is.

Do you happen to have link/image of the optimizer's and or inverter internals? While I can understand why there might be no electrolytic caps in there they'd still need inductors. Given power level involved and modern elements that could probably be done using SMD components but still interesting to see.

If an optimizer fails you are down down just that one pv modules output just like with micros. In any case the optimizers have a much higher reliability than micros.
I have seen some optimizers torn down but no photos. There are very few parts in them due to their use of asics

https://www.solaredge.com/us/solutions/reliability-approach#/

https://www.solaredge.com/sites/default/files/solaredge-reliability-methodology.pdf

[max2k]

If an optimizer fails you are down down just that one pv modules output just like with micros. In any case the optimizers have a much higher reliability than micros.
I have seen some optimizers torn down but no photos. There are very few parts in them due to their use of asics

https://www.solaredge.com/us/solutions/reliability-approach#/

https://www.solaredge.com/sites/default/files/solaredge-reliability-methodology.pdf

well, if they did what they wrote in that doc then they might produced product with reliability significantly exceeding conventional consumer electronics. Use of ASIC doesn't really guarantee anything on its own and might be even source of a problem due to its proprietary nature: I've seen before when manuf to cut down on # of components went with such 'custom' IC practically always leading to higher rate of failures as they typically were lucking experience how to make ICs to begin with.

I would not say SE is guilty there and it would be really dumb on their account to go into much trouble everywhere else but screw up with ASICs. I'm happy to know they went with QFP instead of QFN otherwise I wouldn't even consider them as contender for reliable product. No way QFN soldering would survive 25 year on the roof, glad they caught that themselves.

[bcroe]

Actually there have been 4 deer hanging around (even resting under) the array, but had no
interest in it. I am working on an electric fence to deter them.

An optimizer is a simple DC to DC function, it converts only a fraction of the panel power. A
micro does a far more complex DC to AC isolated function, running at full panel power. Lots
more to go wrong, and its also subject to any line surges that might come along. Lots more
chances for failure. Bruce Roe

[Singuy]

Okay guys, just got another proposal and quote. So far the pricing is decent but the panel's efficiency is pretty subpar for monos.

2.68/watt
Solar Edge Inverter with optimizer
Heliene 72M 335W(yeah 72 cells..not a fan but if it fits...based on him using pvsketch.com, it fits but I'm not sure if I trust these numbers since the other company who actually did measurements can only fit this one part of the roof with 60 cell panels).
.10 cents more per watt if I choose the
Solarworld 290w Mono
He also said I can choose whatever I want..and his other recommendations are LGs and Canadian Solar.

1 Year bumper to bumper warranty
The rest are based on manufacture warranty replacement but labor is not included
10 years performance warranty(or however long the company exist). Basically he is basing on how much estimated power I can generate and he'll pay any difference if my panels cannot generate this amount at the end of every year at 0.12cents/kwh. The numbers I saw are 17200kwh on a 11.4kw hour system..which is very ambitious since pvwatt said I should generate about 16300kwh with a 11.7kw system.

[max2k]

Okay guys, just got another proposal and quote. So far the pricing is decent but the panel's efficiency is pretty subpar for monos.

2.68/watt
Solar Edge Inverter with optimizer
Heliene 72M 335W(yeah 72 cells..not a fan but if it fits...based on him using pvsketch.com, it fits but I'm not sure if I trust these numbers since the other company who actually did measurements can only fit this one part of the roof with 60 cell panels).
.10 cents more per watt if I choose the
Solarworld 290w Mono
He also said I can choose whatever I want..and his other recommendations are LGs and Canadian Solar.

1 Year bumper to bumper warranty
The rest are based on manufacture warranty replacement but labor is not included
10 years performance warranty(or however long the company exist). Basically he is basing on how much estimated power I can generate and he'll pay any difference if my panels cannot generate this amount at the end of every year at 0.12cents/kwh. The numbers I saw are 17200kwh on a 11.4kw hour system..which is very ambitious since pvwatt said I should generate about 16300kwh with a 11.7kw system.

acceptable deal if it comes like that. I'd pay extra 10 c for SW panels or whatever other well known brand he offers. The estimated output is too optimistic- I'd get that much in SoCal with practically perfect roof location/orientation (azimuth 220-230 south west). So far my LG305N1K-G4 panels produced close to 100% non-derated PvWatts estimate: 1,335Wh vs 1,200 Wh PvWatts derated by 10%. Please keep in mind panels will reduce their output with age and after 10 years total output is going to be 6-7% down from initial level. Basically I don't understand how installer can guarantee such output .

[J.P.M.]

Okay guys, just got another proposal and quote. So far the pricing is decent but the panel's efficiency is pretty subpar for monos.

2.68/watt
Solar Edge Inverter with optimizer
Heliene 72M 335W(yeah 72 cells..not a fan but if it fits...based on him using pvsketch.com, it fits but I'm not sure if I trust these numbers since the other company who actually did measurements can only fit this one part of the roof with 60 cell panels).
.10 cents more per watt if I choose the
Solarworld 290w Mono
He also said I can choose whatever I want..and his other recommendations are LGs and Canadian Solar.

1 Year bumper to bumper warranty
The rest are based on manufacture warranty replacement but labor is not included
10 years performance warranty(or however long the company exist). Basically he is basing on how much estimated power I can generate and he'll pay any difference if my panels cannot generate this amount at the end of every year at 0.12cents/kwh. The numbers I saw are 17200kwh on a 11.4kw hour system..which is very ambitious since pvwatt said I should generate about 16300kwh with a 11.7kw system.

If I was you, I'd get more quotes after I educated myself more.

There may be some available area lost by going to a 72 cell panel, but without boots on the roof and a tape, it'll be hard to tell. There's nothing inherently more/les efficient 60 vs. 72 cell panels. Eff. will be about the same. The 72 cell units will have ~ 72/60 = 1.2 times the STC Wattage and surface area, but equal (electrical) size arrays will cover about the same area. the 72 cell units will do it with 60/72 = .833 fewer panels. The number of panels doesn't matter. If it was me, I'd stay w/ 60 cell panels. Maybe more wiring but probably a bit more flexibility as well.

Never heard of that panel. Doesn't make it bad, just unknown to me. What's the price differ. for the LG's ?

How big is the inverter ?

Not all, but many vendors and equip. mfgs. cover labor as well. I'm of the opinion that most warranties are largely marketing hype, but they have their place. I'm not sure how much importance I'd give them in terms of what they're worth. Some maybe, but probably not a whole lot.

What are your roof tilts and azimuths and your zip code ?

[Singuy]

I am thinking about mixing and matching panels. Thinking about using the 60c SW 290 panels on the area where I can yield more kw from this one roof space and using the 72c on the other roof where space is less restrictive. Is this a bad idea to mix and match panel sizes and brands using the Solaredge inverter?

I think going with more efficient mono 60c panels may add 30-40 cents/watt installed and perhaps not worth the money.

[sensij]

I am thinking about mixing and matching panels. Thinking about using the 60c SW 290 panels on the area where I can yield more kw from this one roof space and using the 72c on the other roof where space is less restrictive. Is this a bad idea to mix and match panel sizes and brands using the Solaredge inverter?

I think going with more efficient mono 60c panels may add 30-40 cents/watt installed and perhaps not worth the money.

No trouble mixing and matching with SolarEdge. In residential systems, the optimizers convert the power of the individual panels. They only see other optimizers, not what is feeding them.

[ButchDeal]

I am thinking about mixing and matching panels. Thinking about using the 60c SW 290 panels on the area where I can yield more kw from this one roof space and using the 72c on the other roof where space is less restrictive. Is this a bad idea to mix and match panel sizes and brands using the Solaredge inverter?

I think going with more efficient mono 60c panels may add 30-40 cents/watt installed and perhaps not worth the money.

you can mix and match modules and the optimizers you need on the same inverter with no problem.
likely you would be using P300/P320 on the 60c and P400 on the 72c

https://www.solaredge.com/sites/default/files/application_note_intercompatibility_se_power_optimizers_na.pdf

[Singuy]

Wow, so SolarCity countered. $6700 off the original quote due to the competitor's quote I have uploaded to the sales representative. Most likely will be a delta inverter with SolarCity, not the solar edge(since I have no shading). Confirming if this is with the new Panasonic 335w panels or not since my original quote is with the Panasonic panels. My original quote for 11.7kw at 38k. So final $/watt for solar city is right now at 2.68/watt pre-tax credit. Their warranty is definitely way more robust than any small local shop. 20 year performance guarantee and also bumper to bumper (parts and labor on panels and inverter). Also I think Solarcity will have the highest chance of still being around in 20 years.

If I am getting their high efficiently Panasonic panels(which means way fewer panels on my roof than any other company), then I may be sold on SolarCity at 2.68/watt.