Decisions: inverter, panels, installer

[JW@SPT]

I've received many proposals and need to make a decision. Below are some thoughts and questions. Any advice would be appreciated.

Inverters: SolarEdge with power optimizers vs Enphase IQ7+. My roof has shading issues, from trees and a chimney. I've read string inverters like SE have trouble with this, but don't the power optimizers solve for that? I've read comments about how it's not a good idea to have complex electronics on the roof. It makes perfect sense to me. Why then does SE seem to have much greater reliability issues than Enphase? I've heard/read from multiple installers that about 25%+/- of SE inverters have issues. It's a much lower number for Enphase, so the electronics on the roof seem to do better, which contradicts intuition. Ultimately I want performance and reliability. It seems like a simple goal and with any other product in life it's easier to figure out than solar.

Panels: I've seen Q Cells, REC Alpha and Solaria all presented as a good value. The REC Alpha panels look to be the best across the spec sheet, followed by Solaria and then Q Cells. This site has Q Cells rated the highest. I don't get why REC isn't higher and the best option given the lower degradation and science that's over my head (REC's n-type cells). Also, if I go with an Enphase IQ 7+ (not 7A), then does it make sense to pay up for a 360, 370 or 400 watt panel rather than a 340 Q Cell because of clipping around 295?

Installers: I've seen various proposals with combinations of three panels above and two inverters. If I get six bids, it's like there are 2 for Q Cell, 2 for REC and 2 for Solaria. Then randomly 3 for Enphase and 3 for SE. Good, reputable installers recommend Q Cell panels and SE inverters. Tesla is offering Q Cells and SE w/ power optimizers for $2.00/kWh as many of you know. Other bids are 30 to 60% higher for combinations of the providers above. I've read a lot of horror stories about Tesla. Have they gotten better, with a lot of the issues coming from the Solar City legacy business? Are part of the issues from SE inverters, which seems to be a common issue across installers? The recent reviews on this site seem mostly positive for them. Maybe Solar City was a sketchy company, but Tesla, now an S&P 500 company, should have (or being working towards having) good service.

I've asked a lot of questions and done some rambling, but the ultimate question is should I go with Tesla (Q Cells and SE w/ PO) or a local installer (at 30%+ more), and if so, which panel and which inverter? REC Alpha and Enphase seem like the safest bet to me based on the REC spec sheet and Enphase reviews. My head is spinning.

If it matters, I'm in the northeast and looking at a 10kW system. Thanks!

[khanh dam]

Local installer might have better service and they might go out of business next month.Will there extra service save you the $6000 difference in install price over 25 years? unlikely IMHO. your solar array would have to be out of service for about 4 years to loose $6k in energy production.
Personally I think Tesla will be around in 25 years and is a safer bet. They have bad reviews, like every other big company, but they do thousands of more installs than local company, so what is thier percentage of compalints? Same with solar edge inverts. I read about failures, but what is the percentage?

as far as the panels go they are all the same IMHO, just a cheap commodity at this point in history. buy 2 extra if you are worried about them failing and want to make sure you have spares, because I guarantee you in 3-6 years the same panel will no longer be available. they are super cheap like $40 cents a watt now a days, not sure what mark up would be.

what did they quote as break even time frame? with a 10kw system it's probabaly close to 10 years with tesla and 14 years if local is installing it, unless your state has SREC or utility rebates. both too long a time frame IMHO, good luck.

[JW@SPT]

Thanks, khanh. I'd have steam coming out of my ears if one of the horror stories played out (down for the whole summer), but there's room for it with the savings. Your logic makes sense. I'm in MA which has great incentives ($1,000 rebate and SREC program) plus the federal tax credit so the Tesla break even is around 6 years and others closer to 8 years. But, this assumes I pay out of pocket day 1 and then never am down a day or need to put a nickel into the system again, at least in the breakeven period. To your points about size of company and bad reviews, I tend to agree, but with the inverters, Enphase is a pretty big company. Solarreviews.com has 2.35 stars (53 reviews) for SE and 4.20 for Enphase (401 reviews). Tesla has 2.33 stars on 557 reviews and other local companies are closer to 4.5 to 4.75 on 50 to 100 reviews. Maybe people are more hesitant to bad mouth a company in their backyard, or only come out to write reviews when there are issues with Tesla, or Tesla does cut corners to keep costs down, and some people pay for it. I go between the financial modelling with room for error like you said, while hoping for the no disasters with Tesla, or "do it once and do it right" with confidence in the installer and system. It will be on my roof for 25 years+ so I probably shouldn't cut corners or I'll regret it for a long time. I am leaning towards your logic, but this is just the other perspective in my mind. Thanks for your response.

[khanh dam]

So the people that loose $500 worth of energy over the summer probabaly do not mention that Tesla saved them $6000 overall in cost is that fair? Also it is a well known fact that people are more inclined to write a negative review than positive. so the more installs a company does the increase in negative reviews it is not proportional. I bank with Wells Fargo, look at their horrible reviews, but they have never done bad to me. almost impossible to obtain the real data. a company that has been around 20 + years taht sells solar products to a bunch of installeers would have the best knowledge of what products actually fail under warranty. most stuff either fails right away or in thecase of solar panels takes 6 to 10 years for corrosion and pid issues to show.

[khanh dam]

who ever you choose , sit on the roof and make sure they do nto walk on the panels, and all the flashing and rails is installed good, make sure they put nox on the mc4 connectors and weather proof tape them too, those are most common failure points 8 years down the road and only takes an extra 30 to 60 minutes to give them the extra protection. an inverter failing is an easy swap out. changing out a bad connector on a panle in the middle of the roof is more involved.

[JW@SPT]

Ok...so after your 11:25am response I was ready to say, I agree and can no longer refute your points. Green light.

The roof is about a 37 degree pitch on a second floor. I won't be sitting on it on checking the things you said which I'm sure are sensible but I mostly don't understand. I could ask before installation to confirm they'll do these things, but this is over my head. I'm closer to trusting that the installer is honest and competent but I don't have the capability to monitor and verify.

I appreciate the feedback - thank you.

[khanh dam]

just buy the waterproofing self sealing tape and a bottle of no-ox and give it to the installers the day they arrive. it just prevents water from getting between the connections between each panel