Advice needed for solar roof installation

[EVCar]

If there's even a remote chance for any roof work, I'll do the roof first and then the solar panels.
I didn't think about this so had to spend, I think, $2K to remove and re-install the solar panels for a new roof later.

 

[Tesla2.0]

I'm in Tucson, using TEP, and my system is 32kW - no power walls. Of course that was installed about 5 years ago by Solar City (now Tesla Energy). It was the largest residential system at the time. Which power company do you have?

Now getting Solar Power to coming in to quote.

I’m in Gexa Energy for retail in ERCOT grid.

 

[SubSailor]

I'm in Tucson, using TEP, and my system is 32kW - no power walls. Of course that was installed about 5 years ago by Solar City (now Tesla Energy). It was the largest residential system at the time. Which power company do you have?

Trico Coop

 

[Alex]

Trico Coop

That’s a real bummer. I’m in the process of designing/building a new home at Saguaro Ranch and will need about 32-48kW of solar. Trico services the area, but with a 9.6kW restriction, it makes it ‘hard’. I was planning on a Tesla solar (shingle) roof with multiple power walls.

 

[SubSailor]

That’s a real bummer. I’m in the process of designing/building a new home at Saguaro Ranch and will need about 32-48kW of solar. Trico services the area, but with a 9.6kW restriction, it makes it ‘hard’. I was planning on a Tesla solar (shingle) roof with multiple power walls.

I would contact Trico "Sun Watts" and ask them what the latest data and restrictions are. You might have different parameters today. Good Luck.

 

[GEWC]

Yes, which I understand that. I want to 2 PowerWall. He was trying to sell me without PowerWall. He said, I can just get it from grid at night in off-peak hours rate and sell excessive power at peak-power rate. I told him but I need it for rain storm to keep my house and internet uninterrupted. He reluctantly put 1 PowerWall in but told me cannot put 2 PW bc supply chain bottle issue I have to add it later; and it takes long time for them to get more PW. I wasn’t sure if he was BS or he was afraid to lose me as customer if I get shocked by too much equipment cost.

DO NOT BELIEVE THIS. They do not let you add powerwalls after the fact. Their system literally does not allow it. Also 2 powerwalls is very low for that system. We have a 16+kw system with 2 PWs and 3 invertors. I had asked for 4 powerwalls and they gave us the same spiel, convinced my husband 2 were enough (i was away) and we've been fighting with them ever since. Also, they can only hook 2 powerwalls up to each 140 volt meter, so be aware of what your system needs. We have a 240 volt system so only half the house is backed up (and the wrong half - our biggest fight with them). I will add that you got a great price - ours was more than double that.

SunRun is a great company. We have their panels in San Diego and their customer service before, during and after install is excellent. They were at our house today fixing a broken invertor that they noticed.

 

[GEWC]

That’s a real bummer. I’m in the process of designing/building a new home at Saguaro Ranch and will need about 32-48kW of solar. Trico services the area, but with a 9.6kW restriction, it makes it ‘hard’. I was planning on a Tesla solar (shingle) roof with multiple power walls.

Restrictions are usually individualized, in my experience, though that was with SDGE. They wouldn't let solar cover more than 80% of expected use, I believe. They did let us add more panels once we got a 2nd EV.

 

[GEWC]

One more negative about Tesla, from what I have heard, most people wait several (6+) months for them to even submit the paperwork to turn the system on. This was one area where we lucked out. Ours was submitted immediately and approved in 6 weeks.

 

[SubSailor]

Restrictions are usually individualized, in my experience, though that was with SDGE. They wouldn't let solar cover more than 80% of expected use, I believe. They did let us add more panels once we got a 2nd EV.

This is the Trico blurb sent when asked-
What are the limitations of installing solar panels in Arizona?


There are physical limitations you need to consider such as how much space you have on your roof or on your land to install solar panels. The state of Arizona sets a maximum system size limit of 125% of the customer’s total connected load.
This limitation and my available roof space is the reason I installed 9.6skW system. As mentioned, you may have a different set of limits that your home has to meet . Not sure on 32-49kW solar....that is a lot of solar panels!!!!

 

[EVCar]

Restrictions are usually individualized, in my experience, though that was with SDGE. They wouldn't let solar cover more than 80% of expected use, I believe. They did let us add more panels once we got a 2nd EV.

I'm a bit ignorant on this but just curious what's the justification for utility companies to place such restrictions.
They never pay a good price for the excess anyway. So why not take advantage of customers who have the space and the means and helping the environment at the same time?

 

[Alex]

I would contact Trico "Sun Watts" and ask them what the latest data and restrictions are. You might have different parameters today. Good Luck.

I have emailed them for specifics for my area, but this is what they say on their website:

* System qualifications are calculated using 12 months of metering history as of the date of completion of this form. These calculations are subject to change based upon the date of the Interconnection Application review.*​

Trico Electric Cooperative's current DG Energy Export Tariff states that the generating capacity must be less than or equal to 125% of the customer's total connected load, or in the absence of Customer load data, capacity less than or equal to the Customer's electric service drop capacity. Connected load is determined by peak demand in the last 12 months (accounting for existing renewables). In addition to this requirement, Trico will review the existing service equipment (transformers and other facilities) to see if it may need to be upgraded or supplemented. Trico will also review the number of PV systems currently interconnected to the transformer and other facilities. The load of all PV systems on a transformer cannot be more than 75% the size of the transformer, and the systems cannot exceed the requirements of other facilities.​

In my case, since the house is not fully designed (or built), I can go with the service drop capacity (400A-600A in my case). There is a transformer servicing 4 lots, but mine is the only one actively. being developed, so transformer max. would not be a consideration.

 

[Tesla2.0]

DO NOT BELIEVE THIS. They do not let you add powerwalls after the fact. Their system literally does not allow it. Also 2 powerwalls is very low for that system. We have a 16+kw system with 2 PWs and 3 invertors. I had asked for 4 powerwalls and they gave us the same spiel, convinced my husband 2 were enough (i was away) and we've been fighting with them ever since. Also, they can only hook 2 powerwalls up to each 140 volt meter, so be aware of what your system needs. We have a 240 volt system so only half the house is backed up (and the wrong half - our biggest fight with them). I will add that you got a great price - ours was more than double that.

SunRun is a great company. We have their panels in San Diego and their customer service before, during and after install is excellent. They were at our house today fixing a broken invertor that they noticed.

Did you have SunRun or Testla installed?

 

[riverstrand]

if you are buying a lucid why do you want a power wall. with bidirectional capability your car can serve as your power backup?

 

[SubSailor]

I have emailed them for specifics for my area, but this is what they say on their website:

* System qualifications are calculated using 12 months of metering history as of the date of completion of this form. These calculations are subject to change based upon the date of the Interconnection Application review.*​

Trico Electric Cooperative's current DG Energy Export Tariff states that the generating capacity must be less than or equal to 125% of the customer's total connected load, or in the absence of Customer load data, capacity less than or equal to the Customer's electric service drop capacity. Connected load is determined by peak demand in the last 12 months (accounting for existing renewables). In addition to this requirement, Trico will review the existing service equipment (transformers and other facilities) to see if it may need to be upgraded or supplemented. Trico will also review the number of PV systems currently interconnected to the transformer and other facilities. The load of all PV systems on a transformer cannot be more than 75% the size of the transformer, and the systems cannot exceed the requirements of other facilities.​

In my case, since the house is not fully designed (or built), I can go with the service drop capacity (400A-600A in my case). There is a transformer servicing 4 lots, but mine is the only one actively. being developed, so transformer max. would not be a consideration.

In your case, I would go for a 400-600 amp panel with separate garage subpanel with at least 2 separate EV 100 amp circuits. You could "future proof" home for EV charging stations. When you get to your electrical, make sure to utilize all copper wiring and correct NEMA gauge for load usage. Even then, have them use metal conduit inside walls and attic for the large loads.
I have to admit, I am not a big fan of using my new Lucid Air GT to supply power to my home so the PowerWalls would be my choice anyway. Battery technology is finally getting attention and will be improving dramatically IMO as we go forward. Lucid's 520 range will be eclipsed within 2 or 3 years as more and more effort is devoted to the battery systems.
I believe we will revert back to nuclear power before long. The waste problem will be solved and safety measures can be imp;roved so it will be America's answer to our aging power grid problem. I rode nuclear subs for 23 years so feel very at ease with the technology.
Good luck on new home design and build...always fun to do and incorporate the latest designs and improvements as well as utilize the best features available. Hope to see you around the area when we get our Lucids. I am wearing out my 2019 Tesla Model 3LR and actually am looking at getting a used 2022 Model S via private seller.

 

[Tesla2.0]

if you are buying a lucid why do you want a power wall. with bidirectional capability your car can serve as your power backup?

That is an option until Lucid’s special wall charger is here.
Also having PowerWall can have interruption free during grid outage. At night, solar panels are not drawing power, so have to use stored battery at night to not tap in grid.

 

[Bunnylebowski]

Panel Manufacturer: Hanwha Q-Cells with SnapNRack racking
Model number: Q.PEAK DUO ML-G10+ 410
Quantity: 50

Inverter Manufacturer: SolarEdge Techologies
Model Number: SE6000H-USSN
Quantity: 1
Model Number: SE10000H-USSN
Quantity: 1

Battery Manufacturer: LG Chem
Model number: RESU 10H Prime
Quantity: 1

Equipment - Costco - $26,891
Installation - SunRun - $53,940

This is the system I just had installed for $43K after tax credit. I really love how the panels look as they just look like black mirrors with no lines and fit seamlessly with the roof, barely notice them. Waiting for RI Energy to approve and turn it on. I got an 8kw system, which I thought was tiny but I guess I'm accidentally really energy efficient already as the most KWh I've used in a month is 798, but the panels should exceed my energy usage even with charging the Lucid occasionally. I think the efficiency is from the Mitsubishi air-source heat pumps combined with a brick house.

 

[Tesla2.0]

This is the system I just had installed for $43K after tax credit. I really love how the panels look as they just look like black mirrors with no lines and fit seamlessly with the roof, barely notice them. Waiting for RI Energy to approve and turn it on. I got an 8kw system, which I thought was tiny but I guess I'm accidentally really energy efficient already as the most KWh I've used in a month is 798, but the panels should exceed my energy usage even with charging the Lucid occasionally. I think the efficiency is from the Mitsubishi air-source heat pumps combined with a brick house.

I appreciate your input for my comparison reference.

 

[borski]

4 Powerwalls? How many days last you for an extended power outage?

A while, but less long than you’d think. My electric bill prior to solar was 700-800/month. Big house, two ACs, ridiculous amount of light bulbs (LED, but still), etc. The house used to be owned by commercial electricians, so there is just lighting everywhere; the upside of this is the house gets a straight 400A of service, which is useful.

 

[borski]

I’ll try Sunpower (I got several quotes for my system but did not reach out to them). I wonder if their panel advantage has faded though. Per their website their panels have 55% better efficiency, but looking at the specs their panels, at 400w, are in line with the competitors (my quotes ranged from 390w-405w panels). Their baseline for the “55% better claim” is a 17% efficiency 280w panel- not sure if that reflects reality in 2022.

Interested by @Tesla2.0 Costco pricing. I tried SunRun directly but they weren’t close to being competitive price wise in NY. If Costco membership brings that down significantly it would definitely be worth the cost of a membership.

Currently Tesla has given me the best pricing but they are not offering microinverters as an option (string inverter only), so they are out because of that. Project Solar is only slightly higher, but they are a relatively new company so a bit of an unknown, and then daylight to the rest of the group.

SunPower’s degradation or performance warranty is 92% after 25 years. That means that over 25 years, your panels will only degrade 8%, which is better than any other panel out there.

Plus their panels themselves are the highest efficiency there is, meaning you could likely get fewer panels.

Overall, it *is* more costly than other makers, but it’s a premium product. YMMV.

 

[borski]

if you are buying a lucid why do you want a power wall. with bidirectional capability your car can serve as your power backup?

1) My car isn’t always at home
2) the ability to cost arbitrage and not use power from the grid during peak times
3) don’t want to degrade the lucid battery that much