Operation after install

[Charlesz]

Hi guys. I’m having my 19.2Kw panels plus 2 power wall install today. They finish most of the installation and will come back tomorrow to finish up. Questions is can I turn on the system prior to town inspection and PTO?

 

[karkrazy]

They should have told you or given some instructions before they left. Officially, you cannot turn it on until PTO otherwise you’ll be responsible for all damages to the grid blah blah blah…

But some testing is generally allowable. Again, your installers should have given some direction

 

[holeydonut]

The other risk to worry about is maybe your meter can't "run backwards". In some jurisdictions exporting to the grid could end up recording that energy was used from the grid. For some PTO's the PoCo has to come to the house and slap on a new meter.

So there's a chance you kind of screw yourself exporting solar before PTO.

But I'm 99% sure simply banking your own solar into your own batteries and not exporting to the grid is totally cool pre-PTO.

 

[Charlesz]

For some reason I believe the meter have been pre-swapped my utility bi have already shown a credit bank with 0 before installation

 

[Unclepaul]

Tesla told me not to turn on till acceptance by Utility. Will need final permit sign off prior to energizing. Patience is required here.

 

[jrweiss98020]

If you want to test it legally, open the main breaker to disconnect from the grid, then close the breakers from the solar panels and powerwalls.

 

[jboy210]

I tested mine during the 4 months wait for the city to come to inspect the installation plus the additional 2 months for PG&E to grant PTO. I was very careful to monitor the Powerwall's state of charge and shut the inverters down when I reached 90%. I also plug my cars in every day. Some days it felt like I was running around looking for a place to dump a bucket of electrons.

 

[Charlesz]

So the install is complete today by noon. The installer have turn on the system for me. However it started generated only 1kw from my 19.2kw system. Installer says it’s the trees on my south side creating a large shade. It peaks at 3.6kw around 2pm and by 3:30 it dropped down to 1kw due to sunset. Is it the trees or is it something else?

 

[jjrandorin]

So the install is complete today by noon. The installer have turn on the system for me. However it started generated only 1kw from my 19.2kw system. Installer says it’s the trees on my south side creating a large shade. It peaks at 3.6kw around 2pm and by 3:30 it dropped down to 1kw due to sunset. Is it the trees or is it something else?

If your installer said "trees" its probably trees (we would have zero way / information to speculate otherwise).

One thing I will tell you though, is for most of the US, the lowest amount of power you will generate on a clear, sunny day will be between the end of november and february.

You dont judge production by days, but by weeks (and months), so you may not want to hear this at all, but your half day production on a brand new system isnt really relevant as to what its going to produce or not.

If I was in your shoes I would probably test it tomorrow (all day) but I also would know that your 19.2kW system will likely never hit 19.2kW peak production, especially at any point in the winter (but likely not at any point, ever).

I also think thats a very large system for 2 powerwalls, so I am going to assume (and I realize that assuming is generally bad) that your system is spread all over on multiple roof planes / cardinal directions so your daily generation might be longer but the peak production lower.

If not, I hope you dont run into an issue if you were to test this system during the summer of it generating too much PV for your powerwalls to handle during a power outage.

 

[jboy210]

So the install is complete today by noon. The installer have turn on the system for me. However it started generated only 1kw from my 19.2kw system. Installer says it’s the trees on my south side creating a large shade. It peaks at 3.6kw around 2pm and by 3:30 it dropped down to 1kw due to sunset. Is it the trees or is it something else?

Shading is a major issue this time of year. And with the sun so low the days are short even without shading.

According to the Tesla app, my 12.75 kW roof generated 7.8 kWh today. Peaked at 1.8 kW today. Shading, some clouds, and winter solstice (Dec 21-shortest amount of daylight) all lead to low production for us. The same system does close to 55 kWh/day in early June when the sun is high, and the days are still relatively cool.

 

[Charlesz]

If your installer said "trees" its probably trees (we would have zero way / information to speculate otherwise).

One thing I will tell you though, is for most of the US, the lowest amount of power you will generate on a clear, sunny day will be between the end of november and february.

You dont judge production by days, but by weeks (and months), so you may not want to hear this at all, but your half day production on a brand new system isnt really relevant as to what its going to produce or not.

If I was in your shoes I would probably test it tomorrow (all day) but I also would know that your 19.2kW system will likely never hit 19.2kW peak production, especially at any point in the winter (but likely not at any point, ever).

I also think thats a very large system for 2 powerwalls, so I am going to assume (and I realize that assuming is generally bad) that your system is spread all over on multiple roof planes / cardinal directions so your daily generation might be longer but the peak production lower.

If not, I hope you dont run into an issue if you were to test this system during the summer of it generating too much PV for your powerwalls to handle during a power outage.

Yes I have about 20 panels face west 23 panels faceing east and 5 panels facing north. tilting 26 degree. There is 8 trees on my south side covering up all the sun during the wintertime which Im planning to get a tree guy to trim it, Hopefully that will help increase production during the winter months. My entire house is running off electric right now with brand new mitsubishi hyper heatpump and a new 24kw hot water heater. Plus my Model X plaid I dont think Ill ever have to worry about generate too much energy for my batterypacks to handle.

 

[jjrandorin]

Yes I have about 20 panels face west 23 panels faceing east and 5 panels facing north. tilting 26 degree. There is 8 trees on my south side covering up all the sun during the wintertime which Im planning to get a tree guy to trim it, Hopefully that will help increase production during the winter months. My entire house is running off electric right now with brand new mitsubishi hyper heatpump and a new 24kw hot water heater. Plus my Model X plaid I dont think Ill ever have to worry about generate too much energy for my batterypacks to handle.

Your powerwalls can only take 10kW input, together, so I would recommend keeping an eye on generation numbers when you get to march, april, etc. If they go above 10kW peak during that time, then during a power outage you may not have the results you expect.

In any case, if I was in your shoes I would probably run the system most of the day on a day that had full sun, so I could see what it looked like, understanding that between now and winter solstice is about is bad as a sunny day will look.

 

[Charlesz]

Shading is a major issue this time of year. And with the sun so low the days are short even without shading.

According to the Tesla app, my 12.75 kW roof generated 7.8 kWh today. Peaked at 1.8 kW today. Shading, some clouds, and winter solstice (Dec 21-shortest amount of daylight) all lead to low production for us. The same system does close to 55 kWh/day in early June when the sun is high, and the days are still relatively cool.

thank you for that insight. The app shows me I generated 7.1kw today from 12:30pm turn on time to about 4pm sun set. Im just making sure that they have connected all my panels right.