There has been no resolution, nearly 4 months after install. Tesla has largely ignoredmany many contact attmpts after switching to a Delta M-10-US inverter/no optimizers, not as promised and has seriously poor production issues as detailed below. The short of it is that minimal shading, with almost 30 panels in full sun (and less than a quarter of panels shaded) this delta M10 +12kw 36 panel system makes ZERO output. It could/should be producing for at least 2 more hours. (let’s skip discussing its severe problems dealing with a few thin clouds flying by for now).
"CUSTOMER LAYOUT", PLANS submitted and APPROVED by city, right up to install day, were for 12kw array (36x340w qcell G6 duo), SolarEdge 10k inverter, 36xP400 optimizers, 3 powerwalls. Known shading issue, which I clarified verbally early on and insisted on seeing the plans for (and I had from Tesla and verified from the City). I had obtained bids on comparable systems from other providers. Went with Tesla, bit lower price and was thinking they would back up their install if I later have problems (learning hard lesson here). Price: $48,000 cash. 4 months of being almost entirely ignored is not convincing they would ever back anything up.
INSTALLATION day was Friday 02/19/2021. That morning, install team lead called me and said there would be some delay as they were still trying to get the right parts from another warehouse. (I should have made them re-schedule I guess). At this point we also discussed that the 125 A distribution panel would manage future items and I asked him to get a 200a instead. He agreed. They showed up 3 hours later and said its all handled and began installing. When they were ready to leave I was checking things and we had a Delta M-10 inverter installed. I asked the installer and he said "it’s the same thing". He left the system powered up and told me if I shut it off, I might not get it on again. I did my homework and Delta doesn’t have optimizers, only "middle circuit interrupters" (fancy name for a rapid shut down, RSS; they are NOT bypass diodes).
MY ARRAY BEHAVIOR: by about 3:40pm (see pictures) lower quadrant of array is shaded; almost 30 panels are in full sun (probably good enough to max this M10's clipping point of 8.8kw), some of the panels in string 1, and 1 of the panels of string 2 are shade covered. This causes production to drop to ZERO. This is highly consistent every day. The left 12 panels are string 1, the right 24 panels are combined into another MPPT (junction upper right arrow). The behavior is NOT gracefully degraded producing power from the remaining panels in sun (as e.g.
@nwdiver suggests would always happen). Note these uploads are from a completely clear day. My array’s behavior is like Solaredge (SE) technical papers suggest for non-optimized arrays (
https://www.solaredge.com/sites/default/files/se_technical_bypass_diode_effect_in_shading.pdf).
Compare to my neighbor's system, at a similar angle to the sun and with a similar shading issue in the afternoons. It’s a 4kw array on a 4k inverter with modules under each panel (optimizers or external bypass diodes). See (picture 3) the shading as it begins 4pm for his system. See the notably graceful afternoon degradation in the output graph (picture 4), which continues to produce significant output for 2+ more hours. After many weeks pouring through tech data (of my now-part-time research job! Thanks Tesla :/), I am sure this is the NORMAL behavior if there are optimizers or micro-inverters on the system.
HOW TESLA HANDLES THE COMPLAINT
TESLA GRABBED some CRAP off the SELF at the last second and slapped it on my house, contrary to prior agreements, then plays hanky-panky games for months… here’s the timeline.
On the next business day after install, Monday 2/22/21, I notified (and continued to many times) Tesla that the SE inverter/optimizers were swapped out to a Delta w/out optimizers, without my consent, and I wanted it corrected, as it’s not what they promised. That same day I found a newly submitted planset (sub’ed on 02/22/21) to my city with SE inverter and P400's removed and an M10 in place. Tesla dated this as 2/10/21, but I know that was “back dated”, as the 200 A panel I talked about was in there and it wasn’t even discussed til 02/19/21). Through the following days and weeks I contacted through calls, emails mobile app trouble reports, etc. Numerous contacts and messages, VM etc .... IGNORED. Much later I was able to get a "backup" project adviser to answer through various calls, and they promised they would escalate. Never happened, many contacts later went unanswered. Eventually (3/30/21), I was contacted by "HCI" that my inspection was scheduled ... for that very same day. Exactly 30 mins later the city inspector arrived at my door... but Tesla did not arrive with a copy of the plans. I told the inspector they didn’t install what we had agreed to and I don’t want inspection. He wrote it down as "not ready" and left. A number of unanswered contact attempts and weeks later... and I find in my account that I was assigned a new "project advisor" in my account. I sent a detailed email, timeline and pictures, plans, etc to her wanting them to have a supervisor talk to me. She seemed very concerned and "escalated" the problem. I spoke to who I thought was an operations supervisor, but now suspect was an alternate salesperson. After he told me various things I am sure now are incorrect, (delta are superior in every way, don’t need any optimizers, optimizers don’t do anything anyway unless you have “all over shading”, SE is nothing but problems, SE produces poorly. etc.), he agreed to send out a team to “inspect” my array and see if there is a compromise we can come up with.
A full team arrived on 05/03/21. This was the first sign of any action in over 2 mos. (Interestingly, this same day HCI calls again saying I am ready for an inspection). I showed this team the nature of the shading through the day, including output graphs and pictures I had been taking across many days at various times of the day. We walked though the property so I could show him where the shading comes from in the morning and afternoon, and I gave him hard copies of shading pictures and how they relate to output, as well as the Solaredge+optimizers approved plans and layout, etc, which they took with them. They dismantled my entire array (yes, completely removed all panels) to check if anything was wrong. They found that there should have been one more MCI than was in there (predictably, this later turns out not to affect array behavior at all). After discussion of the shading patterns and output behavior across the days, the team lead said Tesla doesn’t install optimizers for this inverter, nor did they install bypass diodes on module arrays (turns out that every plan i found for solar /roof/ uses external bypass diodes throughout). He suggested a partial mitigation was to add another string, as the delta m10 only allows 2 strings/MPPTs. He called around (while the team slept in my driveway) trying to get some mgmt to agree to a resolution. Eventually he said he was sending a suggestion that a second smaller inverter be added to add additional MPPT(s) and pull a third string down. This would take mgmt 2 weeks to sign off on.
3 weeks later (05/24/21) I get a call from HCI that they are scheduling inspection because the optimizers have been installed (Oh really?). I say no, nothing was done at all. I wanted to know a name of who told her the work was done; she won’t give one. I start calling about Tesla, eventually get (days later) what seems to be an alternate "project advisor" (not mine) on the phone, who apparently can't find any notes in my account of the things I just described above. He says that there was a note in there and says that my "system is producing exactly as expected" (really? I suspect now it was just more sales b-s, like the CSR that tells you “yes sir you have to top of the line” …no matter what you have.) I explained the zero production when the majority of the array is in sun, and that whatever (if anything) they did to decide it’s “as expected” probably didn’t look at any of the print outs I gave them. They didn’t even have notes that the team was here, or importantly, what the team lead that came to inspect to system recommended. So, he promised to "escalate" the issue, and supposedly added note of what i said the team lead recommendations were (including the name of lead i provided being CC'ed, like the CSR was trying to threaten me that I’d be found out if I was making things up), and they would provide a resolution.
By 06/06/2021, I had no contact. So, I sent a detailed email to project advisor, the "op supervisor" and to tesla energy, etc, including shading photos, output graphs, and the history of the project, with subject line HAVE OPERATIONS SUPERVISOR CALL ME TO CORRECT MY ERRONSOUSLY INSTALLED SYSTEM. Another week later now (06/13/21), no call back, no email, nothing.
Summary? VERY POOR BUSINESS PRACTICE by Tesla (incompetence, or dishonesty). This "deal" is quite similar to: agree to buy an F350 4x4 for $48k, to use for towing; deliver a F150 RWD; say sorry we didn’t have a F350 today; oh, you owe us $48k for an F150 instead; an F150 is still a truck, right? 4x4 doesn’t do anything (as long as it’s in full sun) and an F150 has the same towing power anyway (uh, no).
A $48k cash purchase and they secretly slip me an equipment downgrade (clearly not performing as expected), ignore me, and hold their hand out for full sticker. Ab-solute-ly ridiculous.
WHY DID THEY DO THIS? The comments on the phone the morning of install suggested they didn’t have the SE inverter in the warehouse on the install day. I found at least 5 other people on this forum that had plans approved including SE/optimizers, in a similar timeframe (later 2020) that "mysteriously" instead had a delta arrive .... one of them said he refused install (checked their equip before letting them do anything I guess) and complained and later actually received a SE inverter/optimizers. Another said he complained about the delta, finally (only a month later?) got a SE installed and is getting 20% greater output (totally consistent with my estimates if my array "gracefully degraded, at least 10kwh/day more =20+%). When I asked the team lead on 5/3/21 if they could just install SE, he said there might be a problem getting management to agree to that, because Tesla is shifting to using only their own inverters. I think Tesla decided to stop purchasing SE at some time early 2021, and didn’t coordinate with any of the designers, didn’t tell installers, and the installers just grab something else off the shelf and, and if you notice, try to get you to take it, acting like it’s the same (its "an inverter", i guess). This isn’t even as innocent as “bait and switch” this is bait and then deliver the wrong product then pretend it’s the same and want the same money.
TESLA MAKES MORE PROFIT and the CUSTOMER get’s the SHORT END OF THE STICK. Delta (with no optimizers) from what I can tell on the web (there is piss-poor documentation on it, but I did find some asian suppliers that would sell it to me) is FAAAR CHEAPER than a SolarEdge. This equipment downgrade probably “saved” Tesla $2,000+ in equipment costs. They don’t care if it produces reasonably well; that’s my problem. And they think I am supposed to pay the same amount for it. The really weird thing is they sent a whole 5 man crew here for a full day to do NOTHING really. I guess it was for show. By sending the crew out, they probably spent half the money it would have taken to put in the optimizers already and accomplished nothing but wasting my time and theirs.
