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Review of Two House Solar Installations - 12kW and 8 kW - in SW FL

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
We’ve just completed our second Tesla solar installation, a mid-sized 8 kW system on our SW Florida rental property, following on the heels of a larger 12 kW system that we installed in January on a brand new house (eventually our primary residence), while the just-installed 8 kW system was a retrofit to a five-year-old rental property.

1) Technology, overall quality and value for the dollar – A. Good panels (midrange, not the most expensive/watt or highest output either), Solar Edge DC optimizers and inverter, excellent output overall, sometimes – under optimal conditions – exceeding the peak output rating for each system. Likely easily exceeding yearly kilowatt hour estimates (not confirmed yet, as we have only had 4.5 months of experience with our older system and just barely one month with the newer system) but the 4.5 month old system is way ahead of its predicted output. Both systems (each specified with two Tesla Powerwalls) were under everybody else's prices with the same two batteries, although prices on just panels with installation were fairly similar across several reputable outfits. But where Tesla really beats up on the competition is around Powerwall prices – and there really isn't much competition in the marketplace for the Powerwall either – they are pretty much it in terms of storage options. And Tesla batteries are not cheap at $13,000 for two, which is the sweet spot for reasonable energy storage for the average (~2000 sq ft) house in Florida. The Tesla Gateway (the brains of the system so to speak) is brilliant, allowing a seamless integration of three potential power sources (batteries, grid, and solar cells) while managing load in relationship to your house, and funneling excess output from your solar system either into batteries or backfeeding into the grid. Its operation is completely invisible to the homeowner, in terms of how it juggles potential sources, targets and load. If power goes out, you barely notice a discernible dimming of the lights. The Gateway’s operation is depicted in app ‘power flow’ screen. 2nd pic is our 8kW system output.
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2) Installation process and quality – A. We had our builder observing the first system install (he himself is highly technically competent and knows a lot about solar), and he said the Tesla group was a real ‘A’ team, at least as good as his install group. Entire system installed in a day. This rating only pertains to our install team which is out of the Tampa FL office. But they were really, really good. The second system had to have the installation location of some panels modified on the fly so to speak, due to the absence of crawl space on one side of the house, and everything appears to have been successfully modified in terms of the panel placements, without any ‘hit’ on the system’s max and overall output.
upload_2020-5-23_12-48-9.png

clip_image006.jpg

upload_2020-5-23_12-47-16.png upload_2020-5-23_12-48-9.png upload_2020-5-23_12-42-31.png upload_2020-5-23_12-44-53.png
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3) System design and customization – B/B+. There was quite a bit of variability on this, and the B grade might be an average across some real highs and lows. Our first system was designed pretty optimally from my standpoint (A), although they did not include coverage for the pool system and a 4.5 kW pool heater if the power fails – but probably the pool pump could have been broken out and covered even if the pool heater might have exceeded capacity. However on our second house design, they did not even initially include coverage for the house A/C which is just ridiculous in Florida (and where the AC system only draws 3.5 kW). I had to insist on a redesign so that this was included in the covered loads, and also had to challenge their panel placement on the second system, such that the south-facing roof panels were raised up to the higher section of the roof to avoid being shaded by a tree. The redesign triggered a re-pricing, where they mistakenly included Florida sales tax on Powerwalls (a $900 error that I then had to call their attention to in order to get it corrected). I would strongly recommend you go over the design carefully before agreeing to it or signing off on it, in view of these kinds of gaffes. I would also make sure that their pricing sheet numbers are accurate and reflect what's on their website, including whether State taxes should or should not be applied.

4) App for system and quality of its digital information – A+. This app is ‘way cool’ frankly and I would bet that it sells a lot of systems, because it tells you exactly what's going on in real time. It's really a game changer in my estimation, as it gives the owner an enormous amount of information that can be easily gathered. App has excellent organization and a neatly tabbed information structure. It can also support downloads. Armed with the app and its various subpanels, you can see real time consumption and house loads. This allowed me to diagnose, for example, the deteriorating efficiency of our rental property AC (as it started to use upwards of 45 kW/hr/day!), in order to get timely service before failure. A coolant recharge (it was down at least ½ lb) resulted in an immediate 40% drop in AC power consumption. This probably saved us $300 in summer energy bills. All your major house loads can be seen and visualized in the app as they initially come on line and begin drawing power – you can see for example on our new house (somewhat surprisingly) that the pool heater takes almost twice the power (4.5 kW) that the house AC (2.5 kW) does. You are put in charge so to speak of your energy consumption in a way that you simply could never be without a real time live monitor of kW. All this is free, from the app. The app is an industry best, and just a screaming home run in my opinion. It’s worth the price of admission. The info gathered by the Gateway and transferred to the App about consumption from grid vs. backfeeding to the grid is uncannily accurate, varying only a minimal amounts once in a while from what readings the power company generates. This image below is from our larger 12 kW system, which exceeds our consumption every month, unless we are charging the cars a lot. We are more than 300 kWh ahead for May (not driving due to COVID-19 has meant ~1/5th the mileage.
upload_2020-5-23_12-47-16.png
upload_2020-5-23_12-47-16.png upload_2020-5-23_12-42-31.png upload_2020-5-23_12-44-53.png
clip_image010.jpg


5) Communication from Tesla – B-/C+ and this might be generous. This was literally all over the board. Sometimes it was excellent (A), other times it was almost nonexistent and I just couldn't reach anybody (D), sometimes Tesla failed completely to inform me of critical issues and simply disappeared (F). Their communication with the power company and the County was also similarly variable. This resulted (in concert with Charlotte County’s endless foot dragging and long delays in permitting, including problems in getting dates from FPL to disconnect and reconnect during the second install) in a five month delay to getting the system installed. Part of the problem appears to be that there's no one person at Tesla bird-dogging your system installation and there are frequent handoffs from one energy rep to another. They admit this is an area where they need improvement, and I would agree.

Overall grade – A-. The superb app with its abundance of usable data, the overall high value for the money, the high-quality installation teams (at least in our Southwest Florida area), and the systems consistent performance at or above spec vastly outweigh the sometimes spotty communication from Tesla with buyers and power company/County third parties, the occasional sloppy attention to details in system planning, and other kinds of ultimately minor quality control issues. Also, and critically important to the overall A- grade, when they make a mistake they take responsibility for it, and eventually get it right. In other words, I was never worried that I was being scammed, treated not in good faith, or dealing with any version of sociopathy/dishonesty/corner cutting. This is really important, because there are some sleazy solar installation outfits out there. Tesla, in our experience, is clearly not one of them.

Although the addition of two batteries blows up our payback period, and is not absolutely essential in areas with true net metering, I have high confidence that the system will perform its intended function for many years. With the Powerwalls, we are now pretty much blackout-proof and protected against power outages at both houses – assuming a hurricane or tornado does not rip the panels off the roof, and they are rated to 160 mph winds down here, as part of our building code. But for folks where the local power utility offers true net metering, and where power outages are rare, you can get a high value system with a relatively short payback period by omitting the Powerwalls. Either way, I overall recommend Tesla as a company to go to for a home solar system install. I do wish that there was a bit more variation beyond 4, 8, 12, and 16 kW systems, but reducing variation has helped them be much more competitive in terms of pricing. I would not hesitate to recommend Tesla for folks in Southwest Florida looking for sustainable energy, and energy independence. It's really a remarkable feeling to know that your home is self-sufficient in a way that it had never been before, and that you are now powering your car simply from sunshine. It's an amazing feeling to know that you are both saving an enormous amount of money over the long term, while having a virtually zero carbon footprint residence and transportation system.
 
Last edited:

tcoombes

Supporting Member
Jan 22, 2018
1,066
3,373
Northern California
We’ve just completed our second Tesla solar installation, a mid-sized 8 kW system on our SW Florida rental property, following on the heels of a larger 12 kW system that we installed in January on a brand new house (eventually our primary residence), while the just-installed 8 kW system was a retrofit to a five-year-old rental property.

1) Technology, overall quality and value for the dollar – A. Good panels (midrange, not the most expensive/watt or highest output either), Solar Edge DC optimizers and inverter, excellent output overall, sometimes – under optimal conditions – exceeding the peak output rating for each system. Likely easily exceeding yearly kilowatt hour estimates (not confirmed yet, as we have only had 4.5 months of experience with our older system and just barely one month with the newer system) but the 4.5 month old system is way ahead of its predicted output. Both systems (each specified with two Tesla Powerwalls) were under everybody else's prices with the same two batteries, although prices on just panels with installation were fairly similar across several reputable outfits. But where Tesla really beats up on the competition is around Powerwall prices – and there really isn't much competition in the marketplace for the Powerwall either – they are pretty much it in terms of storage options. And Tesla batteries are not cheap at $13,000 for two, which is the sweet spot for reasonable energy storage for the average (~2000 sq ft) house in Florida. The Tesla Gateway (the brains of the system so to speak) is brilliant, allowing a seamless integration of three potential power sources (batteries, grid, and solar cells) while managing load in relationship to your house, and funneling excess output from your solar system either into batteries or backfeeding into the grid. Its operation is completely invisible to the homeowner, in terms of how it juggles potential sources, targets and load. If power goes out, you barely notice a discernible dimming of the lights. The Gateway’s operation is depicted in app ‘power flow’ screen. 2nd pic is our 8kW system output.
clip_image002.jpg
clip_image004.jpg

View attachment 544187 View attachment 544187
View attachment 544188
View attachment 544188

2) Installation process and quality – A. We had our builder observing the first system install (he himself is highly technically competent and knows a lot about solar), and he said the Tesla group was a real ‘A’ team, at least as good as his install group. Entire system installed in a day. This rating only pertains to our install team which is out of the Tampa FL office. But they were really, really good. The second system had to have the installation location of some panels modified on the fly so to speak, due to the absence of crawl space on one side of the house, and everything appears to have been successfully modified in terms of the panel placements, without any ‘hit’ on the system’s max and overall output.
View attachment 544190
clip_image006.jpg

View attachment 544189 View attachment 544190 View attachment 544187 View attachment 544188
clip_image008.jpg

View attachment 544191

3) System design and customization – B/B+. There was quite a bit of variability on this, and the B grade might be an average across some real highs and lows. Our first system was designed pretty optimally from my standpoint (A), although they did not include coverage for the pool system and a 4.5 kW pool heater if the power fails – but probably the pool pump could have been broken out and covered even if the pool heater might have exceeded capacity. However on our second house design, they did not even initially include coverage for the house A/C which is just ridiculous in Florida (and where the AC system only draws 3.5 kW). I had to insist on a redesign so that this was included in the covered loads, and also had to challenge their panel placement on the second system, such that the south-facing roof panels were raised up to the higher section of the roof to avoid being shaded by a tree. The redesign triggered a re-pricing, where they mistakenly included Florida sales tax on Powerwalls (a $900 error that I then had to call their attention to in order to get it corrected). I would strongly recommend you go over the design carefully before agreeing to it or signing off on it, in view of these kinds of gaffes. I would also make sure that their pricing sheet numbers are accurate and reflect what's on their website, including whether State taxes should or should not be applied.

4) App for system and quality of its digital information – A+. This app is ‘way cool’ frankly and I would bet that it sells a lot of systems, because it tells you exactly what's going on in real time. It's really a game changer in my estimation, as it gives the owner an enormous amount of information that can be easily gathered. App has excellent organization and a neatly tabbed information structure. It can also support downloads. Armed with the app and its various subpanels, you can see real time consumption and house loads. This allowed me to diagnose, for example, the deteriorating efficiency of our rental property AC (as it started to use upwards of 45 kW/hr/day!), in order to get timely service before failure. A coolant recharge (it was down at least ½ lb) resulted in an immediate 40% drop in AC power consumption. This probably saved us $300 in summer energy bills. All your major house loads can be seen and visualized in the app as they initially come on line and begin drawing power – you can see for example on our new house (somewhat surprisingly) that the pool heater takes almost twice the power (4.5 kW) that the house AC (2.5 kW) does. You are put in charge so to speak of your energy consumption in a way that you simply could never be without a real time live monitor of kW. All this is free, from the app. The app is an industry best, and just a screaming home run in my opinion. It’s worth the price of admission. The info gathered by the Gateway and transferred to the App about consumption from grid vs. backfeeding to the grid is uncannily accurate, varying only a minimal amounts once in a while from what readings the power company generates. This image below is from our larger 12 kW system, which exceeds our consumption every month, unless we are charging the cars a lot. We are more than 300 kWh ahead for May (not driving due to COVID-19 has meant ~1/5th the mileage.
View attachment 544189View attachment 544189 View attachment 544187 View attachment 544188
clip_image010.jpg


5) Communication from Tesla – B-/C+ and this might be generous. This was literally all over the board. Sometimes it was excellent (A), other times it was almost nonexistent and I just couldn't reach anybody (D), sometimes Tesla failed completely to inform me of critical issues and simply disappeared (F). Their communication with the power company and the County was also similarly variable. This resulted (in concert with Charlotte County’s endless foot dragging and long delays in permitting, including problems in getting dates from FPL to disconnect and reconnect during the second install) in a five month delay to getting the system installed. Part of the problem appears to be that there's no one person at Tesla bird-dogging your system installation and there are frequent handoffs from one energy rep to another. They admit this is an area where they need improvement, and I would agree.

Overall grade – A-. The superb app with its abundance of usable data, the overall high value for the money, the high-quality installation teams (at least in our Southwest Florida area), and the systems consistent performance at or above spec vastly outweigh the sometimes spotty communication from Tesla with buyers and power company/County third parties, the occasional sloppy attention to details in system planning, and other kinds of ultimately minor quality control issues. Also, and critically important to the overall A- grade, when they make a mistake they take responsibility for it, and eventually get it right. In other words, I was never worried that I was being scammed, treated not in good faith, or dealing with any version of sociopathy/dishonesty/corner cutting. This is really important, because there are some sleazy solar installation outfits out there. Tesla, in our experience, is clearly not one of them.

Although the addition of two batteries blows up our payback period, and is not absolutely essential in areas with true net metering, I have high confidence that the system will perform its intended function for many years. With the Powerwalls, we are now pretty much blackout-proof and protected against power outages at both houses – assuming a hurricane or tornado does not rip the panels off the roof, and they are rated to 160 mph winds down here, as part of our building code. But for folks where the local power utility offers true net metering, and where power outages are rare, you can get a high value system with a relatively short payback period by omitting the Powerwalls. Either way, I overall recommend Tesla as a company to go to for a home solar system install. I do wish that there was a bit more variation beyond 4, 8, 12, and 16 kW systems, but reducing variation has helped them be much more competitive in terms of pricing. I would not hesitate to recommend Tesla for folks in Southwest Florida looking for sustainable energy, and energy independence. It's really a remarkable feeling to know that your home is self-sufficient in a way that it had never been before, and that you are now powering your car simply from sunshine. It's an amazing feeling to know that you are both saving an enormous amount of money over the long term, while having a virtually zero carbon footprint residence and transportation system.

Excellent review and write-up - thank you! I have been thinking about Tesla solar and Powerwalls for a while now and have been hesitant based on reports of delays, installation issues, product and software quality, and communication. It sounds like Tesla is improving significantly in capability and maturity. You have a couple of very nice systems.
 
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dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
Excellent review and write-up - thank you! I have been thinking about Tesla solar and Powerwalls for a while now and have been hesitant based on reports of delays, installation issues, product and software quality, and communication. It sounds like Tesla is improving significantly in capability and maturity. You have a couple of very nice systems.

Thanks for the gracious comments. Yeah overall we really love them. They're fantastic once they get installed and you get past the hiccups. They just work. And even the smaller system really cranks out a lot of power. We're seeing 45 to 50 kilowatt hours as a Max for that system. And we think 70+ kilowatt hours might be the max for our bigger system. That's just a boat load of electricity!
 
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Reactions: tcoombes
May 9, 2020
32
12
Fort Worth, TX
Awesome review. Thank you for taking the time to share. I'm in Fort Worth, TX and I'm deciding on if I should do one or two power wall units. I have net metering here as well, and power failure isn't really an issue here.

I'm really considering just one Powerwall instead of two. I see they have caution tape around, it looks professional. I even see fall protection. I wonder if they would let you go on the roof to check things out while they are up there?
 
Last edited:

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
Awesome review. Thank you for taking the time to share. I'm in Fort Worth, TX and I'm deciding on if I should do one or two power wall units. I have net metering here as well, and power failure isn't really an issue here.

I'm really considering just one Powerwall instead of two. I see they have caution tape around, it looks professional. I even see fall protection. I wonder if they would let you go on the roof to check things out while they are up there?

Probably not. They are liable since it's their job site so they probably would be very unhappy if you started climbing up on the roof. But if you give them a cell phone I think they'd be happy to take pictures of anything up there that you're interested in visualizing.
 

mstgkillr

Member
May 24, 2020
67
47
Cape Coral
Excellent review! Thanks for the post!

I also live in SW Florida (Cape Coral) and just started researching standby generators for hurricane season, which eventually led me to the Powerwalls. I read that South Miami's mayor went off grid for 7 days in a trial run for hurricane season with solar and Powerwalls. I understand Powerwalls, for sustained power outages, is impossible without solar, so here I am.

Tesla.com recommend a 15.12 kW system with 4 Powerwalls, but I'm not sure if I have enough roof space left after the pool solar heating panels. The next size down is a 11.34 kW system with 3 Powerwalls, which should fit, but I would rather due 2 Powerwalls (less expensive) if they would be sufficient for off grid use. Also, even if I had enough roof space left, it would be considered Tier II, which requires additional liability insurance.

After researching the last 12 months of power use, with absolutely no power conservation in place, I used 20,687 kWH. The average, maximum, minimum daily usage was 58 kWH, 113 kWH, and 23 kWH, respectively. This year should be better (long story). I was able to run my entire house without load shedding, including my Trane XV20i 4-ton HVAC (variable system), pool, and well equipment, with the exception of the dryer, range, and hot water heater, on a Honda EU7000is inverter generator rated at 7kW starting and 5.5 kW continuous.

I am considering financing this project through PACE or Telsa, however that works out.
  • How did you get a 12 kW system from Telsa? They only show a 11.34 kW system online.
  • What is your average power consumption at the 12 kW house?
  • How long could you go off grid with decent conditions, during hurricane season?
  • I see that you have an 8 kW system at your rental, which I assume is an investment property... did that system make financial sense? With the smaller 11.34 kW system and 3 Powerwalls, even with the incentives, I am looking at $50/month more than my current average electric bill and I am not sure if it will completely offset my bill.
  • I understand that Tesla doesn't manufacture the PV panels or inverters... can you spec the PV panel and microinverters used?
  • Do Telsa employees perform the work, or is it subcontracted out to a local solar installer?
  • What made you choose Telsa solar over Enphase?
  • I've read some good things about Enphase Enpower...
 

charlesj

Active Member
Oct 22, 2019
1,142
236
Monterey, CA
Great review.
Just a comment on that garage floor I noticed that I wish I had done in my new garage some time back.
That is I noticed tire spots where car is parked. Costco sells, as staple item or periodic, large roll of garage mats that fits under entire car.
I placed two, one for each car, but way after build that now has black squares where car parked, not coming up.
 

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
Excellent review! Thanks for the post!

I also live in SW Florida (Cape Coral) and just started researching standby generators for hurricane season, which eventually led me to the Powerwalls. I read that South Miami's mayor went off grid for 7 days in a trial run for hurricane season with solar and Powerwalls. I understand Powerwalls, for sustained power outages, is impossible without solar, so here I am.

Tesla.com recommend a 15.12 kW system with 4 Powerwalls, but I'm not sure if I have enough roof space left after the pool solar heating panels. The next size down is a 11.34 kW system with 3 Powerwalls, which should fit, but I would rather due 2 Powerwalls (less expensive) if they would be sufficient for off grid use. Also, even if I had enough roof space left, it would be considered Tier II, which requires additional liability insurance.

After researching the last 12 months of power use, with absolutely no power conservation in place, I used 20,687 kWH. The average, maximum, minimum daily usage was 58 kWH, 113 kWH, and 23 kWH, respectively. This year should be better (long story). I was able to run my entire house without load shedding, including my Trane XV20i 4-ton HVAC (variable system), pool, and well equipment, with the exception of the dryer, range, and hot water heater, on a Honda EU7000is inverter generator rated at 7kW starting and 5.5 kW continuous.

I am considering financing this project through PACE or Telsa, however that works out.
  • How did you get a 12 kW system from Telsa? They only show a 11.34 kW system online.
  • What is your average power consumption at the 12 kW house?
  • How long could you go off grid with decent conditions, during hurricane season?
  • I see that you have an 8 kW system at your rental, which I assume is an investment property... did that system make financial sense? With the smaller 11.34 kW system and 3 Powerwalls, even with the incentives, I am looking at $50/month more than my current average electric bill and I am not sure if it will completely offset my bill.
  • I understand that Tesla doesn't manufacture the PV panels or inverters...h can you spec the PV panel and microinverters used?
  • Do Telsa employees perform the work, or is it subcontracted out to a local solar installer?
  • What made you choose Telsa solar over Enphase?
  • I've read some good things about Enphase Enpower...

1) I think with 37 panels my bigger system is 11.67 kW or something like that. You might be able to get them to add additional panel here or there to their modular 4kW block approach, which w/38 panels total would get you to 12kW, but the problem is that if your (rated) AC output goes over 10kW, you will need to get additional liability insurance in relationship to the power company (at least in a lot of areas). So my system size is the sweet spot of max power, and least hassle.

2) average power consumption is about 1200-1300 kW/hr per month, but that has been with little car charging. This is about 200-250 kW/hr lower than average monthly solar production. We have free SC use, but no easily available SC unless we go to Ft Myers or Sarasota, so around town mileage which has been very low due to COVID19 would easily blow that amount up.

3) Indefinitely. The house could run off grid forever, if we didn't need to do a lot of car charging.

4) Yes, getting PW for the rental was an indulgence. Expect to get that back only on sale of house, but without that, system would have been about $20k or so, so reasonable payback period at $150/month electric bill.

5) Solar edge DC optimizers, Q.antum panels from German outfit.
upload_2020-5-24_15-24-38.png

upload_2020-5-24_15-27-56.png


6) Tesla does the installation. I choose them because of A) best price; B) we own two Model 3 DMP which have been amazing vehicles to own and operate. Don't know much about endphase. Didn't get estimate from them.
 
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Reactions: TheTalkingMule

ThomasD

Active Member
Nov 22, 2019
1,043
440
Breckenridge Co Ky
I wish I could afford Solar and a few powerwalls Oh well I guess I'm stuck with my generator. The good thing is I can power a window A/C unit The bad thing is it uses gas Can you charge the power walls through a generator if there is not enough sun for solar after a storm Can I run 220 v items off of the powerwall
 

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
I wish I could afford Solar and a few powerwalls Oh well I guess I'm stuck with my generator. The good thing is I can power a window A/C unit The bad thing is it uses gas Can you charge the power walls through a generator if there is not enough sun for solar after a storm Can I run 220 v items off of the powerwall

I suspect you could get powerwalls installed to an existing house and then charge them from a generator if your generator had a 240 output. If a powerwall is properly integrated into your house system it can both accept 240 and output that voltage.
 
Last edited:

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
Can you post pictures of the completed install on this house? I’ve just ordered a 15kW system for my house here in Florida and it has a similar roof. I would love to see how your install came out.
You want pictures of the bigger system or the smaller system?
 

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
Excellent review! Thanks for the post!

I also live in SW Florida (Cape Coral) and just started researching standby generators for hurricane season, which eventually led me to the Powerwalls. I read that South Miami's mayor went off grid for 7 days in a trial run for hurricane season with solar and Powerwalls. I understand Powerwalls, for sustained power outages, is impossible without solar, so here I am.

Tesla.com recommend a 15.12 kW system with 4 Powerwalls, but I'm not sure if I have enough roof space left after the pool solar heating panels. The next size down is a 11.34 kW system with 3 Powerwalls, which should fit, but I would rather due 2 Powerwalls (less expensive) if they would be sufficient for off grid use. Also, even if I had enough roof space left, it would be considered Tier II, which requires additional liability insurance.

After researching the last 12 months of power use, with absolutely no power conservation in place, I used 20,687 kWH. The average, maximum, minimum daily usage was 58 kWH, 113 kWH, and 23 kWH, respectively. This year should be better (long story). I was able to run my entire house without load shedding, including my Trane XV20i 4-ton HVAC (variable system), pool, and well equipment, with the exception of the dryer, range, and hot water heater, on a Honda EU7000is inverter generator rated at 7kW starting and 5.5 kW continuous.

I am considering financing this project through PACE or Telsa, however that works out.
  • How did you get a 12 kW system from Telsa? They only show a 11.34 kW system online.
  • What is your average power consumption at the 12 kW house?
  • How long could you go off grid with decent conditions, during hurricane season?
  • I see that you have an 8 kW system at your rental, which I assume is an investment property... did that system make financial sense? With the smaller 11.34 kW system and 3 Powerwalls, even with the incentives, I am looking at $50/month more than my current average electric bill and I am not sure if it will completely offset my bill.
  • I understand that Tesla doesn't manufacture the PV panels or inverters... can you spec the PV panel and microinverters used?
  • Do Telsa employees perform the work, or is it subcontracted out to a local solar installer?
  • What made you choose Telsa solar over Enphase?
  • I've read some good things about Enphase Enpower...

Your overall load on your house is a little higher than mine but my system (the 12 kilowatt system that is) could easily accommodate a 50 kilowatt hour average consumption. There are probably two months when it might not be able to hit that output number December and January of course depending on weather, but again those months you don't really need any air conditioning so that pulls down your consumption. So I'm not really sure that you need their bigger system with its bigger footprint and liability insurance headaches. We found that at the newer house that has a bigger system the budget-buster is the pool heater (and of course the cars).The pool heater actually pulls significantly more power than the AC (4.5 kW/hour which is almost exactly 1 degree F added temp). So adding 8 degrees of heating (say 78 to 86 F) uses a LOT of power. We have a limit set of four hours of heating, which is still 18kW. But it sounds like you got a solar pool heater so that helps a lot. We wish we had roof space for both the panels and a solar pool heater. But no such luck. That was the big variable in the rental house system limit size. Most of the Prime real estate on the back roof is taken up by the existing pool heater. I'll post some pictures on all list later today.
 
Last edited:

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
So, apparently Tesla doesn't install/service my area of SW Florida (Cape Coral). May I ask where in SW Florida you are located?

Wow that's a bummer! I'm just a little bit north of you in Punta Gorda. That seems really weird? Who is your utility? The other issue is that you can get third party installation of both the Tesla Gateway and the power wall so that you can see the system in the Tesla app. The Gateway in my estimation is a brilliant implementation and it allows for the communication through a cellular link with Tesla servers. They also provide a Wi-Fi linking system but I believe that's really just a backup.
 

mstgkillr

Member
May 24, 2020
67
47
Cape Coral
Wow that's a bummer! I'm just a little bit north of you in Punta Gorda. That seems really weird? Who is your utility? The other issue is that you can get third party installation of both the Tesla Gateway and the power wall so that you can see the system in the Tesla app. The Gateway in my estimation is a brilliant implementation and it allows for the communication through a cellular link with Tesla servers. They also provide a Wi-Fi linking system but I believe that's really just a backup.

I'm 3 miles from Punta Gorda! Maybe I can bother them some more. LCEC is my utility provider.
 

dfwatt

Active Member
Sep 24, 2018
3,092
5,103
FL
I'm 3 miles from Punta Gorda! Maybe I can bother them some more. LCEC is my utility provider.

Never heard of lcec. Are they hostile to solar power?
edit: just heard they get abysmal ratings. Do you have any options to go with Florida Power and Light
 

mstgkillr

Member
May 24, 2020
67
47
Cape Coral
LCEC is supposed to be solar friendly.

Nope, no FP&L option.

Any chance you could PM the contact information of your design consultant? Maybe I could get them to drive an extra 3 miles for the install.
 

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