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  • Need help with this setup

    Ok, Could use some pro's and cons on anything that I may be missing.

    Option 1
    11.050 kw DC / 8,160.0 AC, 14.7KWH estimate 1st year Production
    34 REC N325NP & 34 IQ7-60-2 Inverters

    or option 2

    11,160 DC, / 8,990.0 AC / 14,9KWH Estimate 1st year Production.
    31 REC360AA & 31 IQ7+ 72-2 Inverters.

    Price difference between the 2 systems is 2,000.00
    Other than panel efficiencies which I don't think I will lose $2k worth of production over the life of the panels. Am I missing a reason to go with the Alpha panels over the N series Panels.

    Thanks in advance.

  • #2
    Assuming that this is going to be installed by a vendor, the biggest consideration is finding the best vendor, in terms of quality of installation and long-term support.

    Otherwise, your systems are virtually the same in performance. I'd select the lowest total cost system. In many cases, the 72-cell panels require fewer inverters and less racking material, so make a lower-cost total solution. That's why I suggest you look at the total cost. But in terms of long-term performance, they're very close.
    7kW Roof PV, APsystems QS1 micros, Nissan Leaf EV

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    • #3
      I know i sound like a broken record and we don't know your location, but I recommend against putting electronics on hot roofs. Get a competitor's quote on a string inverter system using these same panels. I recommend SunnyBoy - less expensive, more reliable, and easy to service when the time comes. Why mate highly reliable solar PV panels with less reliable microinverters that are a nightmare to service. PV panels have a 25 year warranty and will last twice that long. Microinverters have a 25 year warranty but last half that long...
      BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installed

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      • #4
        Solarix: That's great advice...as always. But I have a few questions.

        In many locations, I was told that you need to augment SMA Sunny Boy inverters with rapid shutdown boxes to meet rapid shutdown requirements. Is that true? If so, doesn't that mean that you still need electronics on the roof, one per panel?

        If you are in a high-shade environment, do you still give the same advice?

        If you are in a temperate climate, do you still give the same advice?

        Can you say more about what you mean when you say "Microinverters have a 25 year warranty, but last half as long"? Are you saying that the average Microinverter fails in 13 years? Mark Cavanaugh claims that he's installed 1550 Enphase over the years and only had 4 fail, yet he also claims that he's had 6 panels fail in the same time period. That's still statistics of small numbers but seems to suggest differently than your experience. https://www.mcelectrical.com.au/micro-inverters/ Obviously he's biased. No one is completely objective. But his writing is much clearer than most of the advertising hype I've seen and unlike most marketing hype, his writing is full of facts.

        Can you comment on the fact that Enphase has been through so many generations of Microinverters? Their first were clearly a disaster. Is it possible that with all of this experience, they've got their poop together?

        I'm having a hard time finding long-term data on the iQ7 because it hasn't been around that long. Why are you discounting it?

        Thank you.
        7kW Roof PV, APsystems QS1 micros, Nissan Leaf EV

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        • #5
          My .02....

          I decided to go Solar Edge here in southern Nevada vs. an Enphase approach. I actually like their design better,; liking the highly modular design. However, based on comments here on this board (you can see my recent thread), but doing homework on my own, talking to local installers here in NV, I found evidence of reduced performance shown to me at high heat on actual Enphase systems. Not failures of the IQ7+ microinverters, but performance degradation during days of high heat, great Sun. Same PV panels feeding a solar edge inverter vs. Same panel feeding a Solar Edge.

          Nowhere could I find any Enphase OEM documents that described this behavior.

          On the other hand, I heard (from Enphase proponents), of quality issues with Solar Edge inverters. I know Sunrun dumped Solar Edge. I know a few folks that work there and they said one of the primary reasons was a. qualitY issues, and b. # of truck rolls after 3 or 4 years.

          even my installer I chose (who would go either way based on my decision at same price), acknowledged some premature failures "in the past", but have not seen them at same rate as of 2019. Solar Edge has replaced any units not performing as expected, and they showed me there spare pools at thier location (1 to 2%) of install base. He recommended Solar Edge for our climate. With all of these data points, I decided to go solar edge.

          I did look at Sunny Boy as I do not have any shade issues. However, I feel the reporting g is superior on either the enphase of Solar Edge solution. I also felt very good about either US or Israeli R&D designs over other OEM designs, and I am willing to pay more for those designs and financial stability (Panasonic is the PV panels I am going with). The installer has a solid track record, probably the most the most important aspect of the overall solution.

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          • #6
            On roof electronics reliability is clearly a controversial subject. Definitely, conventional wisdom of keeping electronics cool and the early history of both Enphase and Solaredge lead to not trusting on-roof electronics. The newer versions from these companies may well be better, but the jury is still out and their keeping the failure rate data "close to the vest" doesn't lead me to change my mind. I will admit to being biased on this subject after the horrible failure rate and poor service support I received from Solaredge back in the early days...

            Yes, SunnyBoy string inverters do need TS4 RSD units on each PV module in order to meet the 2017 code. This is still the most economic, most durable inverter choice however. I will say that this Rapid Shutdown requirement is of negligible value to fire safety at a substantial increase in solar installed cost, is a big decrease in reliability and serviceability, and was largely promoted into the code by the two companies that benefit from it. I call B.S. on the Rapid Shutdown rule....

            With triple MPPT inputs, the SunnyBoy technology is almost as good at shade mitigation without the liabilities of on-roof electronics. Besides, you are much better off doing whatever it takes to provide shade free exposure to your array than to try and mitigate a shady array with on-roof electronics.

            Frankly, I wouldn't use SolarEdge or Enphase even in a temperate climate. Maybe they are OK on small systems of less than 10 panels.
            BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installed

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            • #7
              How do you start a new subject? First time user

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              • #8
                Start a new post instructions:
                Log in
                Got to http://www.solarpaneltalk.com or Click FORUMS
                Select the forum most appropriate to your subject
                Click + New Topic
                7kW Roof PV, APsystems QS1 micros, Nissan Leaf EV

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                • #9
                  Solarix, You make many good points. I'm just trying to separate facts from judgments and from bias.

                  As to Sunny Boy being the most economic choice, I have many quotes and run the math. APsystems QS1 is significantly cheaper yet equal or better in every performance regard. Built in, it has per-panel MPPT, per-panel reporting, rapid-shutdown, high efficiency, and easy installation, and comes in dramatically cheaper than Sunny Boy, Enphase, Fronius, or Solar Edge. I'm not pushing for it or even recommending it, but since you claimed Sunny Boy is the most economical, I had to mention that there is a less expensive alternative. Get some quotes if you doubt me.

                  The only open question is reliability - you're right - we don't know. APsystems had bad reliability on their early products. So did Enphase, Solar Edge, and others. Do you remember when Ford was considered the least reliable thing on the road? They do pretty well today, as do most auto makers. The auto industry has matured and taken quality seriously.

                  If a manufacturer is willing to do thorough engineering, install quality components, and monitor their vendors and factories, rooftop electronics can have a long life, even in hot climates. My company makes parts that fly in space, in aeroplanes, under the hood of cars, at the bottom of oil wells, and everywhere else. These can be much more extreme temperatures than rooftops. It can be done.

                  I sure hope the solar industry eventually gets it right.
                  7kW Roof PV, APsystems QS1 micros, Nissan Leaf EV

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                  • #10
                    Originally posted by Lorrainelamb View Post
                    How do you start a new subject? First time user
                    Near the top:
                    NewTopic.jpg
                    Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
                    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
                    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

                    solar: http://tinyurl.com/LMR-Solar
                    gen: http://tinyurl.com/LMR-Lister

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                    • #11
                      I said - most economical / most reliable. There is a lot of cheaper stuff out there that is less expensive and cheaply made....

                      Name me any other consumer product that is warrantied for more than 1 year. Because solar PV panels are so incredibly durable and are warranted for 25 years, the solar industry tries to match that with the rest of the equipment. Solar inverters are a hard working piece of electrical gear and trying to get ten years out ot them is not easy. Your average manufacturer cannot do it. Yes, there iare a lot of industrial, space, and military applications that are high rel - but they cost way more too....
                      Last edited by solarix; 05-28-2020, 02:44 PM.
                      BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installed

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                      • #12
                        This discussion is getting academic, because we really agree. Solar panels are very dependable. From what I hear, when they fail, it's most often that the bypass diode fails...unless someone drops a rock on it.

                        Your signature shows that you have lots of experience with Solar installations. Do you have failure statistics from current-model hardware that you've installed? This kind of data is really hard to get. Mark Cavanaugh's data is the only stuff I've found that seems at all believable.

                        For what it's worth, I have APsystems installed at my home. So far, they have been trouble free, but that's a relatively short time with a small sample. From what I can tell, it is not cheaply made. The housing is all thick metal and seems better made than the Enphase housings. Their connectors, meh, not the best, but they work. I never opened one to see what's inside. We'll see how long it lasts. They claim over 70K installations and 25% of the microinverter market. I think they are a far cry from the cheap junque saturating ebay. Whether they're as good as Enphase, Fronius, SMA, or Solar Edge, I don't know, but they are in the same tier of the market.

                        So again, be careful of bias without data.

                        Seeing that you asked about warranty, automobiles are often warranted for 3 to 7 years. Come to think of it, home roofs are warranted for an amazingly long time 25-50 years, but good luck getting them to stand behind the warranty. Craftsman (and Harbor Freight?) hand tools are warranted for life, whatever that means. Sears doesn't have much life left in them. I just did a google search for products with lifetime warranty. The list is quite long: knives, yoga mats, socks, backpacks, umbrellas...

                        But I'm just having fun. We still agree that panels are very dependable and electronics is more at-risk. And there's going to be some electronics on most solar roofs: rapid disconnect, optimizer, or microinverter. I just wish there was good statistical data available.
                        7kW Roof PV, APsystems QS1 micros, Nissan Leaf EV

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                        • #13
                          After 7 years and over 3 million panel operating hours there have been 3 failures here. 2 were
                          burned out wiring, and one was a failed AC circuit breaker. Things do get checked regularly to
                          detect any problems. All the original operating panels are still operating.

                          Burned wiring is no fire threat since the panels are not on a roof. Bruce Roe

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                          • #14
                            Sorry, I meant consumer electronic product warranties are virtually never longer than 1 year.
                            BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installed

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