Tesla Solar Install Timeline + Question

[MountainPower]

Hi all,

I wanted to share my timeline for my Tesla Solar install, as I'm seeing a number of horror stories on here, and ask a quick question. Overall I've been blown away by Tesla Solar, with one exception - how they communicate. The following is an example of my experience in the Denver metro area.

The system:

• 8.16 kW system
• No Powerwalls
• Estimated 11,288 kWh annual production (102% of my household needs)

The timeline:

• April 11 - Submitted the deposit online and upload the required photos. This was a Sunday and by the end of the day, I had a project manager texting me and an initial design. I agreed to the design and completed the finance set up that evening.
• April 15 - Tesla communicated that they had begun pulling permits. The permits from my city were issued by the end of the day.
• April 17 - I received approval from my HOA to continue and shared it with the Tesla team.
• April 21 - Everything on Tesla's side is ready to go and I call to schedule installation. I chose April 30.
• April 30 - Tesla team shows up on time. The crew works for Tesla Energy and is experienced, polite, and friendly. They even entertained my toddler's endless questions and showed him around the truck. I was blown away by their professionalism!
• May 5 - The system passes inspection.
• May 14 - I call the utility company to check on the status of my meter swap and receiving Permission to Operate. I'm told Tesla never submitted the final documents. Not good... I called my Tesla installation team (whose direct number I had) and they worked to get the paperwork submitted that day.
• May 19 - Xcel, my local utility company, replaced the meter and gives PTO (they actually turned the system on). We're up and running!

Overall, I'm very happy with how quickly Tesla was able to get the system installed and turned on. The horror stories on here and elsewhere had me paranoid, but ultimately the process went very smooth.

The question:

I've had my system set up for four days now (not a huge sample size), and in that time we've had direct sunlight and clear skies a number of times. My system has yet to generate above 4.3 kW. I'm not expecting to ever hit 8 kW, but I'm not getting close. My main concern is that some of the panels may not be hooked up correctly and aren't working.

• What sort of generation should I be expecting?
• How long should I wait before I contact Tesla?

I hope this post helps others in the future!

 

[taphil]

Sounds similar to me. The most I’ve ever seen is 4.3kW for a few minutes, otherwise usually max at 3.8kW. Not enough production to even power my house and recharge 2 PW.

New solar and Powerwall install, low production?

 

[MountainPower]

I was just reading that thread... doesn't look good. Attaching a photo of the inverter wire configuration.

 

[taphil]

Wiring looks like mine and same unresolved low output….

 

[Electrph]

not sure if missed in your original post but do you have a tesla branded inverter? .. i'm thinking so based on photo you posted
short answer you can go on pvwatts put in your info and estimate your production / extrapalate for your small sample size days / time of year
if certain inverters can ask tesla to allow access so can view individual panel performance (without mapping) .. with tesla inverter i dunno
can call tesla let them know your concerns .. this is prob easiest for you but may be slow to get answer

 

[MountainPower]

Wiring looks like mine and same unresolved low output….

Any luck getting a response from Tesla?

 

[MountainPower]

not sure if missed in your original post but do you have a tesla branded inverter? .. i'm thinking so based on photo you posted
short answer you can go on pvwatts put in your info and estimate your production / extrapalate for your small sample size days / time of year
if certain inverters can ask tesla to allow access so can view individual panel performance (without mapping) .. with tesla inverter i dunno
can call tesla let them know your concerns .. this is prob easiest for you but may be slow to get answer

Yes, it’s a Tesla inverter. Navigating directly to the panel IP doesn’t seem to load. I’ll have to call Tesla tomorrow.

 

[taphil]

Any luck getting a response from Tesla?

Still no PTO for me and no new updates from my thread.

I emailed advisor about expected DC voltage but low (half of expected) amps coming from solar wires/panels if what I was told is true (2 strings of 12 panels in series joined in parallel on the roof), but got no response. In meantime, I shut off the solar panels the breaker/gateway.

 

[MountainPower]

Thanks for the update. I’ve emailed my installer directly. I’ll update with what he reports.

 

[charlesj]

One thing to remember is that you will be limited by the inverter max capability, not panel rating total that is based on a flash test in a lab, not real world.

Also, what is the system orientation? While the time of year is now favorable to getting max out from the overhead sun's arc, sure looks like an issue somewhere.

 

[Electrph]

Thanks for the update. I’ve emailed my installer directly. I’ll update with what he reports.

you may end up having to call tesla to get them going on this ... it is their weakest point communication / response .. ur timeline seems very quick so maybe you will have better luck

 

[SaveOurPlanet]

First of all, in order to look at individual string output you need to first connect to the inverter hotspot from your mobile device or your computer if it is close enough to the inverter, after connected, you need to go to 192.168.92.1 for the inverter web UI. From there you need to login to the inverter status page using just your emailaddress and no password. However, you can only do this within 15 minutes of powering up the inverter, so just turn it off and on and wait till you see the hotspot from your mobile device to do this. The startup self-test takes about 5 minutes, then you would start to see the 4 strings Voltage and Amp going up, but looks like you only have 2 strings (1 and 2) in series then parallel down to the inverter as someone suggested. As for expected output, I was doubtful as well as the best I get is around 82% of the system rated power, then I went back to Tesla FAQ and it is stated to expect 80% in the Summer and 50% in the Winter during midday sun, on average. I searched through the web and pretty much realize that would be the case. I've seen my system peaked way above the rated power output but only for a few seconds, continuous peak output lasting for at least 2 hours are about 80%. So my 6.5 kW is only outputting 5.4 at most continuously for a stretch of 2 hours, but at the end of the day, the energy produced seems to be on target if the weather plays nice. Every location is different even if within a block, your output seems to be a bit low but Tesla should be able to check remotely,

 

[charlesj]

Interestingly I can monitor each panel with my Enphase inverters. A couple of days ago I had power out at 220W on a 215W inverter, the others, 10 years old was hitting 90% of that 215 rating. Granted it didn't last for hours as that would not be the case with an DC to AC ratio of only 1.1. Now if I had a ratio of 1.5, then it would be for hours perhaps 3 hours. So, it depends on inverter size and the ratio after having a good sunny day.

When the system was new, I did hit 225W on all 17 inverters on one day. Never since.

 

[MountainPower]

If someone else has a 8.16 kW system with a Tesla Inverter, would you mind posting a screen shot of your production?

 

[MountainPower]

I spoke to Tesla last week and they said they’re working on a firmware update for the inverter and to expect an improvement this week. I rebooted my inverter this morning and noticed performance has improved. It’s overcast out so I’m not see clipping yet, but it’s much better then yesterday (same weather). I expect to hear back from Tesla by Wednesday, and we’ll have clear skies then. I’ll update when I get confirmation.

 

[MountainPower]

I just logged into the inverter - same firmware number as before. I’m not sure what changed, if anything.

 

[holeydonut]

If someone else has a 8.16 kW system with a Tesla Inverter, would you mind posting a screen shot of your production?

Does Tesla have a bunch of inverters for various applications? Assuming Tesla only makes inverters in step increments of 4 kW, how would a customer know if they got the 4 kW version or the 8 kW version?

My gut is telling me Tesla installed their 4 kW AC inverter on your 8.16 kWp DC array and just called it a day. As others have noted, installers usually sell on DC system size. Very few installers go into detail about the inverter sizing and what that means to you and your system. So while it's common knowledge for industry experts to know how important the inverter is, most customers are caught unaware.

 

[taphil]

The specs label on the side of the inverter lists specs for both 4kW and 8kW inverters, but there's a little sticker at the bottom saying the serial number and 7.6kW inverter.

Who knows if the label is correct.

 

[MountainPower]

When you log into the inverter after a power cycle it tells you right above the serial number

 

[holeydonut]

When you log into the inverter after a power cycle it tells you right above the serial number

View attachment 668251

Gotcha, I hope Tesla can confirm why each of your strings isn't pushing out much DC; so you're only gathering about 4 kW at peak.