NorCal, Tesla 4kw + 1 powerwall

[Wannaretireearly]

So I got my design from Tesla. Let me know your thoughts. Thanks

[Wannaretireearly]

Bump!

[scrambler]

I am not sure what feed back you are looking for here.
This just shows you have 6 panels facing south
Then 3 panels facing East north east
Then 3 panels facing West south west

We have no info on shading on that roof, so it is hard to tell if these are the best choices.
Did you survey shadows are various time of the day to see if you get any from trees or roof obstacles...

Using PVWatt, you could evaluate the production of each array to see the differences or kWh production per watt of panel in each orientation

Below in reddish are areas where it seems there would be better place for the 3 panels that are on the North east roof. But without more details and PVWatts simulations, it is hard to know if they are a real option.
image_13832.jpg

[Wannaretireearly]

Thanks Scrambler. This really helps more than you'd think. I didn't know where go start.
Now I have a few things to think about.
I'll check out pvwatts when I get a sec & try to talk to the designer about your idea with reddish locations.

We don't have any tree shading issues. Roof line shading we get does impact that south facing roof a bit...

[scrambler]

To comment further, the ones I added to the South east roof to the right (8 instead of 6) could be shaded by the left side of the home
The two I show on the south west roof in the middle could also get shade from the roof to its left

[Wannaretireearly]

To comment further, the ones I added to the South east roof to the right (8 instead of 6) could be shaded by the left side of the home
The two I show on the south west roof in the middle could also get shade from the roof to its left

Yup. I think both these locations get some shading from the roofing above them...

[Wannaretireearly]

Quick update. Talked to my rep who helped me add 3 panels to my design (total: 15 panels). Makes me more comfortable/future proof with my current annual use around 7200 kwh. They are working on an updated quote/contract. I also dropped the powerwall. One pw just doesn't seem worth it. 2 too much $. Hope we continue to be lucky with the rolling power outages from pge.
I will continue to consider batteries/backup as prices and options get better next few years.
Site plan for permit is trow AM. Anything I should double check? Should be pretty straightforward with only panels being installed....thanks

[solar_future]

Quick update. Talked to my rep who helped me add 3 panels to my design (total: 15 panels). Makes me more comfortable/future proof with my current annual use around 7200 kwh. They are working on an updated quote/contract. I also dropped the powerwall. One pw just doesn't seem worth it. 2 too much $. Hope we continue to be lucky with the rolling power outages from pge.
I will continue to consider batteries/backup as prices and options get better next few years.
Site plan for permit is trow AM. Anything I should double check? Should be pretty straightforward with only panels being installed....thanks

Didn't previous calculations show that the Powerwall has a positive return on investment because of time of use differential pricing?

[Wannaretireearly]

Didn't previous calculations show that the Powerwall has a positive return on investment because of time of use differential pricing?

It did, to a degree. I dont think those calcs took into account net metering though I'd have to go back and look). It's been a tough decision for me: I wasn't happy 1 powerwall would provide very limited backup, and would require significant re-wiring for limited backup. Also, would not be easy to add a second powerwall with more rewiring/panel work needed etc.

Given above, I'm trending towards dropping the batteries, and perhaps pick it back up in a couple of years. Not sure if that's my best decision...

[scrambler]

I find that the capacity of one Powerwall is sufficient to provide great comfort and peace of mind towards foreseeable outages in North California.

During an outage, 80% of the comfort is to keep lights, Internet, computers/TV, washing machines, microwave etc... and for that the equivalent of one Powerwall combined with the fact you can still use Solar is more than enough.

Giving up AC, a big electric oven or dryer for a few days are not a huge deal.

[Wannaretireearly]

I find that the capacity of one Powerwall is sufficient to provide great comfort and peace of mind towards foreseeable outages in North California.

During an outage, 80% of the comfort is to keep lights, Internet, computers/TV, washing machines, microwave etc... and for that the equivalent of one Powerwall combined with the fact you can still use Solar is more than enough.

Giving up AC, a big electric oven or dryer for a few days are not a huge deal.

But would one power wall last more than 12 hours, even with limited use? Agree giving up AC, oven, dryer not a big deal.

How long would you expect one powerwall to keep 80% of your comfort going? Thanks

[scrambler]

In my experience it is more than enough to last through the night and next morning you have solar to recharge and power the house. The combination of the two means I can last indefinitely and comfortably with that setup.
Ultimately, you would need to look at your personal consumption to verify that evaluation. Eventually make a test run over a full day to limit your usage to all the "small loads" and then download the POCO data for that day and look at the hourly usage. and compare that to a day of solar and an evening and night of 10kWh battery.

[Wannaretireearly]

In my experience it is more than enough to last through the night and next morning you have solar to recharge and power the house. The combination of the two means I can last indefinitely and comfortably with that setup.
Ultimately, you would need to look at your personal consumption to verify that evaluation. Eventually make a test run over a full day to limit your usage to all the "small loads" and then download the POCO data for that day and look at the hourly usage. and compare that to a day of solar and an evening and night of 10kWh battery.

Thanks! Great points

[SunEagle]

In my experience it is more than enough to last through the night and next morning you have solar to recharge and power the house. The combination of the two means I can last indefinitely and comfortably with that setup.
Ultimately, you would need to look at your personal consumption to verify that evaluation. Eventually make a test run over a full day to limit your usage to all the "small loads" and then download the POCO data for that day and look at the hourly usage. and compare that to a day of solar and an evening and night of 10kWh battery.

I wish I could limit my energy usage to 10kwh per day but that would require me to send my wife and daughter away somewhere. Neither can do without AC.

[Wannaretireearly]

Its also interesting that solar prices have dropped quite a bit last few years. Whereas the battery prices have gone up. I get the demand from cars is a big impact. Wonder what Powerwall 3 will look like and how aggressive Elon will get with powerwall pricing next few years...